US 2049872 A
Description (OCR text may contain errors)
'/Sfrrr Wfl/f WM5/V708,
S. SERA VACUUM PUMP Aug. 4, 1936. n
Filed'Sepb. 29, 1934 Patented Aug. 4, i936 pirak as ATENT OFFICE:
My invention relates to a vacuum pump, particularly of the manually operable type, and the principal objects of my invention are, to generally improve upon and simplify the construcv tion of the existing forms of vacuum pumps and to provide a pump that may be conveniently'manipulated for establishing a vacuum or partial vacuum within jars or like containers that are utilized for preserving food products orthe like.
Further objects of my invention are, to provide a vacuum pump that includes a cylinder, a piston arranged for operation therein and which piston is carried by a tubular rod, the duct through which has communication with the atmosphere through the handle that is mounted on the upper end of the tubular piston rod for the purpose of manipulating the same.
A further object of my invention is, to provide an improved form oi piston and to combine therewith an expensive spreader, preferably al ring of resilient metal which is effective in maintaining the marginal portion of the piston in intimate contact with the wall of the cylinder.
With the foregoing and other objects ln'view my invention consists in certain novel features of construction and arrangements of parts that will be hereinafter more fully described and claimed and illustrated in the accompanying rdrawing in which:
Fig. 1 is a vertical section taken lengthwise through the center of the vacuum pump of my improved construction.
. Fig. 2 is a detail section showing a modied form of the handle and the outlet from the upper end of the tubular piston rod. ,Y
Fig. 3 is a horizontal section taken on the line 3 3 of Fig. 1. Y
Fig. 4 is a horizontal section taken on the line 4 6 of Fig. 1. Y
Fig. 5 is a detail section of the lower portion of the pump cylinder and showing a modified construction wherein the air vent is located nearthe bottom of the cylinder.
Referring by numerals to the accompanying drawing which illustrates a preferred embodiment of my invention, lll designates a cylinder which may be formed of metal, glass or the like, and the upper end of this cylinder is closed by'a cap l I provided with a centrally arranged opening l2 that serves as a bearing for the tubular piston rod.
There is sufcient clearance in this bearing toL permit air to escapeY upwardly therethrough as the piston rod carrying the piston at its lower end is drawn upwardly through the cylinder.
Mounted on the lower end of cylinder I0, is
(Cl. ZBO- 239) an inverted cup-shaped member I3, preferably n formed of rubber and formed in thecenter of this member is an aperture I4 that establishes communication between the dome-shaped chamber I5 within said member and the lower portion 5 of the chamber within cylinder I0.
Formed integral with member I3, adjacent the opening Ill, are two or more downwardly and inwardly projecting fingers. or studs I6, which are for the purpose of preventing a ball valve or the like that may bedrawn upwardly while the pump' is in use, from closingthe opening I4.
Arranged for reciprocatory movement through bearing I2, is a tubular piston rod I1, and mounted on the upper end thereof is a handle I8, preferably of wood or metal.
The tubular piston rod extends through the center of handle ,I8 and inserted in the upper end of the tube I1, is a plug I9, provided with a head that overlies a portion of the handle I8, adja- 2o cent the upper end of tube I1, thereby retaining the handle firmly in positionon the tube.
Formed through that portion of the wall of tube I1 that is imbedded in handle I8, is an aperture 2 I that communicates with a bore or passage- 25 way 22, that is formed through a part of handle I8. This bore or passageway is arranged'so that its outer end terminates on the outer rounded face at oneV end of the handle so that said passageway may be conveniently closed by applying the thumb or linger to the outer end of said passageway.
Suitably mounted on the end of the tubular piston rod within the cylinder I0, and clamped thereto, preferably by means of a pair of washers 23 and nuts .24, which latter are screw-seated on the tubular pistonV rod, is a piston 25, preferably formed of rubber, leather or exible composition. This piston has the general form of a cup leather washer or packing and the main body portion of said piston is clamped between the washers 23 and the marginal portion of said pistonv extends upwardly at right angles tothe body portion to form a circular flange 26, the outer face of which 5 has sliding contact with the inner face of the cylinder wall.
In order to maintain the exible wall in intimate contact with the cylinder wall, an expanding ring 21, preferably formed of resilient metal and having overlapping ends, is positioned within the wall 26 so as to exert outward Vradial pressure against the same.
In the modied construction illustrated in Fig.
2, the upper portion of the tubular piston rod I1,
exten-ds through the center of the handle and the end of said pistonrod is open as designated by 28 in order to form a port that may be closed by the application of the thumb or finger thereto.
In the use of my improved vacuum pump, the member l is applied to the jar or container from which the air is to be removed and which member is positioned so that it encloses the opening in the cover of the jar and which opening is generally provided with a ball check valve or other conventional form of downwardly seating valve.
The pump is now forced downward to establish an air tight joint between the lower edge of member I3 and the cover of the jar or container and the operator now manually engages handle I8 and after placing the thumb or ngerfover the outer end of the duct 22 to" eiectually close same, draws the handle and tubular piston rod upwardly so as to produce'a vacuum or partial vacuum in the lower portion Aof the cylinder I0 and consequently exhausting the air from the jar or container to which the pump is applied.
'When the desired degree of vacuum is attained, the upward movement of the piston is terminated and the check valve associated with the opening in the jar cover will close by gravity, after which the operators thumb or finger is removed from the end of duct 22 so asto permit air to pass through sai-d duct and through the tubular piston rod to that portion of the chamber within the cylinder below the piston, thus breaking the partial vacuum previously established in the pump bel-ow the piston and with such condition established, the tubular piston rod, the piston carried thereby and the handle will move downwardly to their lowermost positions by gravity.
In the modied construction illustrated in Fig. 5, the piston Ha. of the pump is a solid rod and in order to break the vacuum that is pr-oduced by the. upward movement of the piston an aperture 29 is formed in the wall of cylinder It) near its lower end or the end upon which'the inverted cup is mounted.
In this construction the aperture 29 may be closed by the operators thumb or linger during the suction stroke of the pump piston and when the desired degree of vacuum is produced, the thumb or finger is removed from the aperture, thereby breaking the vacuum in the cylinder below the piston.
An especially desirable feature of myinvention is, the provision of a vacuum pump that is entirely devoid of valves and which latter it will be understood tend to develop air leakage while in service. Y
While my improved vacuum pump is particularly designed for manual use, it may with slight changes be adapted for operation by suitable mechanical or electrical means.
'I'hus it will be seen that I have provided a vacuum pump that is relatively simple in construction, inexpensive of manufacture and very eiective in performing the functions for which it is intended.
It will be understood that minor changes in the size, form and construction of the various parts 10 of my improved vacuum pump may be made and substituted for those herein shown and described without departing from the spirit of the invention, the scope of which is set forth in the appended claims. Y
I claim as my invention:
l. In a vacuum pump, a cylinder, a tubular piston rod arranged for reciprocatory movement in said cylinder, a piston carried by said piston rod within said cylinder, the wall of said cylinder being provided with an aperture that is disposed slightly above the piston when the latter is positioned at its lowermost limit of movement within said cylinder, said piston including a disc shaped body portion, a marginal ange on said body portion and a ring-shaped spreader of resilient material arranged against the inner face of said marginal ilange and having overlapping end portions.
2. In a vacuum pump, a cylinder, a piston rod mounted for reciprocatory movement within said cylinder, said piston rod having a longitudinally disposed duct, the inner end of which communicates with the chamber in the cylinder, the outer end of said duct being open to atmosphere, a piston carried by said piston rod within the cylinder, a handle mounted on the outer end of said piston rod, the wall of said cylinder being provided with an aperture that is disposed slightly above the piston when the latter is positioned at its lowermost limit of movement within said cylinder, a cup of flexible material carried by the distal end of said cylinder, said cup being provided with a centrally arranged opening which communicates with the chamber in said cylinder and a plurality of studs formed integral with said cup adjacent the opening therein.
3. In a vacuum pump, a cylinder, a tubular piston mounted for reciprocatory movement in said cylinder, both ends of which piston rod are open, a piston mounted on said piston rod within the cylinder, a handle carried by the outer end of the tubular piston rod and the wall of said cylinder being provided with an aperture Vthat is located above the piston when the latter is at the lower end of its travel within said cylinder.