Jan. 22 1924. L48L91 L. CHEW ET AL COMPRES S ION PUMP Filed Dec. 9, 1922 2 Sheets-Sheet 1 jam. 22 1924. 1,481,691
L. CHEW ET AL COMPRES S ION PUMP Filed Dec. 9, 1922 2 Sheets-Sheet 2 m- .1. 12 W a wrmyst no STATES LEUIG OEW AND WILLIAMIREDERICK JENNINGS, OF LONDON, ENGLAND.
Application. filed December 9, 1922. Serial No. 605,798.
To all whom it may concern: 7
Be it known that we, LEUIG CHEW and WILLIAM FREDERICK JENNINGS, subsets of the King of Great Britain, and resi ents of London, England, have invented certain new and useful Improvements in Compression Pumps, of which the following is a specification.
This invention relates to improvements in that class of compressor or compression pump as used for refrigerating machines and particularly has reference to the construction of the top side of the iston or cylinder head wherein a plura ity of ring valves are housed.
It is important with the high speed now adopted with this class of compressor that a maximum provision of valve area is obtainable both with the suction valves situated in the head of the iston and in the delivery valves situated 1n the yielding head or cover of the compressor cylinder. Besides it is important that there should be as few loose parts as is possible to avoid the chance of any of such parts as for example split pins, nuts and the like when dislocated dropping into the cylinder.
The object of the present invention is to so house and construct such valves that positively no loose parts can be dislocated and therefore a maximum speed of the compressor obtained without fear of accident and consequently the efiiciency ofthe machine-both as regards suction and delivery of the gas increased.
For the purpose of this description it will suffice to describe our invention as applied to the suction valves of a compressor which:
are housed in the top of the compressor pis ton but as will be evident the lmprovements hereinafter set out are equally applicable to the delivery valves housed in the yielding head or cylinder cover of the machine.
Firstly in order to secure the maximum valve area of any .given piston the surface available is most effectively divided into seven circular valves of equal diameters, one situated in the centre and the other six disposed equi-distantly from and around the central valve. In carrying out our invention this disposition of valves is adopted and the several valves are housed in a disc or plate secured to the top of the piston by means of six valve cover plates with depending stems that are screwed into tapped holes provided in the head of the piston so that the said disc or plate that forms the housing for the several ringl valves becomes a component part of the ead of the piston.
Each of the valve cover plates aforesaid is duodecagonal in shape. The central valve which is similarly formed is provided with a valve cover plate the stem of which passes through the aforesaid disc or plate and is secured to the underside thereof with a spring interposed so that it is free to be lifted for the purpose hereinafter described.
The central valve cover plate is primarily constructed hexagonal in form and provided with duodecagonally disposed projectin flats on its corners which on being turned into position serve as locking means for the valve cover plates of the six valves surrounding the same.
These projections likewise serve for main taining the central valve cover plate when raised in such a position as to permit of the removal of the several valve cover plates around the same, suitable upstandin studs or projections being automatically left on the disc or plate by the act of machining out the several housings for the seven valves by the intersection of the seven circular borings by which said housings are formed.
The central valve cover plate is provided onvits upper surface with a screwed stem to which is applied a .tool with handle that projects beyond the top of the cylinder to facilitate the manipulation of the same. The same tool which is provided with two depending pins also serves the purpose of releasing the several valve coverplates situated around the central valve, the said pins engaging with theperforations provided to allow of a free gas discharge to the topside of the piston.
Given apiston head constructed as above described certain difficulties in regrinding the valves in position are consequent and these difliculties are overcome by the use or application of a circular spring clip which automatically holds the ring valve in position whilst a removable tapered plug with a handle on the top and a stem beneath that fits the bore which normally contains the stem of the valve cover plate, affords a convenient tool for centering the valve in its true position for re inding.
In order that our invention may be readily understood reference may now be had to the accompanying two sheets of drawings in which- Figure l is a sectional elevation of th Similar reference characters relate to like parts in all the figures of the drawin Referring now to Figures 1 an 2 in which are illustrated our improvements applied to the suction valves carried in the head of the piston it will be seen on reference to the plan (Figure 2) that the disc or'plate 2 is provided with six borings or housings 3 on the base of which are provided the seatings 4 with which the ring valves 5 contact. The several housings 3 are disposed hexagonally around the central housing 6, which in fact by the intersection of the several housings consists of the six more or less triangular studs 7 that serve the purpose of maintaining the central valve cover plate in its raised position as previousl referred to.
e plate 2 is secured to the top of the piston 8 by the screwed stems 9 that depend from the valve cover plates 10. The central valve cover plate 11 has a stem 12 that passes through the disc or plate 2 and is secured to the underside thereof by means of the nut 13 with the spring 14 interposed so as to allow the said plate 11 to be lifted as hereinafter described.
Each of the valve cover plates 10 are duodecagonal in form and when in their normal position as seen in Figure 2 they are locked by the interconnection of the pro'ecting members 15 provided on the centralvalve cover plate 11, and the several valve cover plates 10 are thereby retained in position having been screwed into their respective tapped holes in the top of the piston 8. It will be seen that the central valve cover plate 11 is mainly hexagonal in form with projecting membeis 15 duodecagonally disposed so as to agree with the sides or edges of the several valve cover plates 10 such .edges being normally on the same plane as seen in Figure 1.
-In order to remove one or other of the several valve cover plates 10 the central cover plate 11 is provlded with a screw-stud 16 with which is engaged the tool 17 thespindle 18 of which carries a handle and answer extends upwardly preferably beyond the top surface of the cylinder 19.
Given a tool or s anner 17 a plied as shown in Figure 1, t e central v 've cover plate llcan be raised'and turned so that the projections 15 rest upon the top of the of to the top side of the valve cover plates- 10, by the engagement of the depending pins 21 with the holes 22 bored through the top of said valve cover plates each individual valve cover plate 10 can be removed from the top of the piston 8 and upon the removal of the six stems 9 the valves 5 can be taken out and the top disc or plate 2 removed from the top of the piston 8, when the central valve cover plate 11 can also be removed by unscrewing the nut 13.
Beneath each of the cover plates 10 and 11 is provided the boss or guide 23 for the retention of the ring valves 5 in their correct position, this boss 23 is divided into several projecting points 24 by reason of the borings 22 thus reducing the frictional contact of the ring 5 with its guides to a minimum.
The admission of gas to the top side of the piston takes place through the holes 25 which are circularly disposed beneath the ring valves 5 and finds its way past the valve 5 to the top side of the piston throu h the holes 22 and the space between the edge of the valve cover plates 10 and the housings or borings 3.
A thinfibre washer 35 may be inserted between the underside of the boss 23 and the contacting surface of the disc or late 2 to ensure a gas-tight joint and after a means of adjusting the relative position of the side that co-acts with the projecting member 15 of the central valve cover plate 11 by which it is locked or prevented from rotating.
Referring now to Figures 3 to 6, presunr ing one of the valves 5 requires to be reseated or ground in position the valve cover plate 10 is removed and the valve 5 placed on the spring holder or cylinder 26 which is provided with a flange 27 and is expanded by a cone 28 mounted on the stem 29 that carries the handle 30 the underside of the cone 28 carrying a circular dependence 31 which exactl fits the bore 32 which is normally occupled by the part 33 of the screwed stem 9 of the valve cover plate 10 when the valve is assembled in its housing 3. It will be understood that witha moderate amount of pressure applied to the handle 30 the valve 5 will be exactly centered and coincident with the valve seatings 4 in the respective housings 3 of the disc or plate 2 that forms the head of the piston. The valve holder or cylinder 26 is of the usual construction provided with the ordinary saw-cuts 34 in order to secure even expansion on the insert1on of the cone 28, and afiord a gripping efiect on I the ring 5.
Obviously the aggregate areas of the holes 22 and the annular spaces within the housings 3 are made of such dimensions as to at least equal the combined areas due to the lift of the several ring valves 5 so that a free discharge of gas is ensured into the cylinder on each descent of the piston and by the disposition of the valves as aforesaid the maximum available valve area is obtained proportionately to the diameter or area of the piston so fitted.
The component parts of the six outer.
valves being identical they are readily interchangeable.
What we claim is 1. In a compression pump, in combination, a plurality of ring valves, one of said valves being centrally disposed with respect to the remaining valves that are disposed equidistantly from and around said central valve, a disc formed with a central housing for said central valve and similar housings disposed equi-distantly from and around said central housing for the remainder of said valves, a plurality of studs formed by the intersection of said housings, a resiliently mounted cover plate for the central valve, a plurality of fixed cover plates for the remaining valves, locking and interengaging projections on said fixed cover plates and said central cover plate and means for raising and rotating said central cover plate to rest on the aforesaid studs whereby said projections are disengaged permitting removal of the cover plates, substantially as described.
2. In a compression pump, incombination a plurality of ring valves, one of said valves being centrally disposed with respect to the remaining valves that are disposed equi-distantly from and around said central valve, a disc formed with a central housing for said said studs whereby said projections are disengaged permitting removal of the cover plates, and means for holding, centerin and regrinding said ring valves, substantial y as described.
3. In a compression pump, in combination, a plurality of ring valves, one of said valves belng centrally disposed with respect to the remaining valves that are disposed e uidistantl from and around said central va ve, a disc ormed with a central housingfor said central valve and similar housings disposed equi-distantly from and around said central housing for the remainder of said valves, a plurality of studs formed by the intersection of said housings, a resiliently mounted cover plate for the central valve, a plurality of fixed cover lates for the remainmg valves, locking an inter-engaging projections on said fixed cover plates and said central cover plate, an upwardly projecting screw-stud on said central cover plate, a spanner for-engaging said stud, means for raising and rotating said spanner when engaged with said stud, an expansible cylinder for engagement with any one of said ring valves and means for expanding said cylinder and centering said valves, substantially as described.
In testimony whereof we aflix our signatures.
LEUlG CHEW. WILLIAM FREDERICK JENNINGS.