US 3815624 A
One end of a short length of copper tubing is bifurcated for connection with a line to be tapped in straddling relation. The other end of the copper tube surrounds and is connected to an internally threaded bushing. A generally cylindrical centrally bored air valve core equipped housing is threadedly connected at one end portion with the bushing. The bushing connected end of the housing is provided with a coaxial line piercing tip for piercing the line to be tapped as the housing is threadedly engaged with the bushing.
Description (OCR text may contain errors)
United States Patent [191 Mullins COPPER TUBE SERVICE VALVE  Inventor: John W. Mullins, PO. Box 20524,
Oklahoma City, Okla. 73120 221 Filed: Apr. 26, 1973 211 App]. No.: 354,820
Related US. Application Data  Continuation-impart of Ser. No. 137,376, April 26,
1971, Pat. No. 3,732,886.
 US. Cl. 137/318  Int. Cl. B23b 41/08, F16e 41/04  Field of Search 137/315, 317, 318
 References Cited UNITED STATES PATENTS 2,336,173 12/1943 Henderson 137/318 X 3,714,959 2/1973 Pignataro,.lr 137/318 June 11, 1974 Primary Examiner-William R. Cline Assistant Examiner-David R. Matthews Attorney, Agent, or Firm-Robert K. Rhea [5 7] ABSTRACT One end of a short length of copper tubing is bifurcated for connection with a line to be tapped in straddling relation. The other end of the copper tube surrounds and is connected to an internally threaded bushing. A generally cylindrical centrally bored air valve core equipped housing is threadedly connected at one end portion with the bushing. The bushing connected end of the housing is provided with a coaxial line piercing tip for piercing the line to be tapped as the housing is threadedly engaged with the bushing.
3 Claims, 4 Drawing Figures 1 COPPER TUBE SERVICE VALVE CROSS REFERENCE TO RELATED APPLICATION The present invention is a continuation-in-part of my copending patent application Ser. No. 137,376, filed Apr. 26, 1971 for COPPER TUBE SERVICE VALVE, now US. Pat. No. 3,732,886.
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to refrigerant lines and moreparticularly to a refrigerant line tapping service valve. 1
In order to maintain a refrigerating system operable it is necessary to periodically check and service the system and when necessary recharge the system with refrigerant gas. This is easily accomplished by the present invention which provides a valve equipped housing coaxially secured to a relatively short length of thin walled copper tubing wherein the opposite end of the copper tubing is bifurcated to partially surround and be connected, as by soldering,to a refrigerant gas containing copper line, thus providing'access to the bore of the refrigerant line intermediate its ends.
This invention is distinctive over my above referred to copending application by providing an internally threaded bushing which is secured within one end of the bifurcated length of copper tubing prior to its connection with a line to be tapped permitting the use of a centrally bored air valve core equipped housing having threads and a line piercing tip at one end portion for entering the bushing and piercing the line to be tapped. Thus, the bushing equipped short length of copper tub-' ing may be attached, at the time of manufacture, to a.
refrigerant, unit line, so that the line may be tapped by threadedly inserting the valve equipped housing by a repairman, or the like, any time it is desired to provide communication with the bore of the refrigerant line.
2. Description of the Prior Art U.S. Pat. No. 3,162,211 discloses a line penetrating device comprising 'a cutting needle secured to a cap threadedly engaged with clamping means surrounding the linefor forcing the needle through the wall of the line wherein resilient sealing means seals with the clamp means after piercing the line.
This invention is distinctive over this patent by providing a valve opening and closing the bore of a line piercing core which is sealed with the wall of the line, thus eliminating any resilient seal means and the necessity of loosening and retightening the piercing needle each time the line is checked or serviced as disclosed by the patent.
SUMMARY or THE INVENTION A generally cylindrical centrally bored and threaded bushing is coaxially secured within one end portion of a relatively. short length of copper tubing. The other end of the copper tubing is bifurcated by an arcuate recess formed on a radius complemental with the radius of a line to be tapped forming a pair of tube legs partially surrounding opposing side portions of a line to be tapped for connecting the copper tubing, as by soldering, to the line to be tapped which usually comprises copper tubing.
A generally cylindrical centrally bored housing, preferably formed from brass stock for rigidity, is externally threaded and provided with a coaxial centrally bored line piercing tip at one end portion for engagement with the internal threads of the bushing and piercing a line to be tapped when fully engaged threadedly with the bushing. The bore of the housing is internally threaded for receiving an air valve core for opening and closing the bore of the housing. The ends of the housing, opposite its bushing equipped end, is externally threaded for receiving a dust cap, or the like.
The principle object of this invention is to provide a service valve housing and connector which may be easily connected to a line to be tapped with the housing including a line tapping core which is forced into the line by threadedly engaging the housing with the connector.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded perspective view of the valve components and a fragment of a line to be tapped;
FIG. 2 is a side elevational view of the components of FIG. 1 when assembled on the line tobe tapped;
FIG. 3 is a perspective view of the valve housing threadedly engaged with the line connector; and,
FIG. 4 is a vertical cross-sectional view taken substantially along the line 44 of FIG. 2.
DESCRIPTION OF THE PREFERRED EMBODIMENT Like characters of reference designate like parts in those figures of the drawings in which they occur.
The reference numeral 10 indicates the device, as a whole, comprising a housing 12 secured to a line connector 14 in turn mounted on a line 16 to be tapped. The connector l4is preferably formed of the same material and wall thickness as the line to be tapped.
As mentioned hereinabove, in practice, the line 16 usually comprises a length of copper tubing and the connector 14 is similarly formed from a length of copper tubing usually diametrically slightly greater than the diameter of the line 16 for the reasons readily apparent.
One end portion of the copper tubing 14 is bifurcated forming a transverse substantially U-shaped slot through its wall at one end portion defining oppositely disposed connector legs 18 and an arcuate bight portion 20 preferably having a radius complemental with the outside radius of the line 16 for attaching the connector 14 to the line with the legs 18 straddling the line and the connector wall arcuate surface 20 contacting a peripheral portion of the line. The free end portion of the legs 18 usually project beyond the horizontal diameter of the line, as viewed in FIG. 2, pennitting the free end portion of the legs to be crimped or bent inwardly in contacting relation forming a partial wraparound action on the line 16 thus temporarily positioning the connector on the line. The length of the legs defined by the distance between the arcuate surface 20 and the free end surface of the legs 18 is preferably slightly less than the diameter of the line 16 to tapped, as clearly shown in FIGS. 2 and 4.
A cylindrical internally threaded bushing 22, preferably formed from brass stock, or the like, and having a length substantially equal to the length of the connector 14 between its arcuate surface 20 and its end oppo site the legs 18, is closely received by the end of the A connector opposite its legs and is secured therein, as by soldering or brazing before the connector 14 is connected with the line 16 to be tapped.
As shown in FIG. 4, the bushing 22 is centrally drilled, on a' diameter at least equal to the base end or largest diameter of the truncated conical-shaped tip 32. The bushing is then counterbored, forming an annular beveled or tapered seat, facing toward and forming the inner limit of the counterbore. The counterbore is threaded to complete the bushing.
The housing 12 is generally cylindrical, having a central bore 26 extending inwardly from one end and provided with a hexagonal head 28 forming wrench flats, intermediate its ends. One end portion of the housing is diametrically reduced and threaded, as at 30, complemental with the bushing threads 24. This end of the housing is further diametrically reduced to form a coaxial substantially truncated conical line piercing tip 32 which is centrally bored for communication with the housing bore 26. The length of the housing between the free end of its line piercing tip 32 and its hexagonal head 28 is greater than the combined length of the bushing 22 and the wall thickness of the line 16 to be tapped for the purposes readily apparent.
. The wall forming the housing bore 26, at its end opposite the tip 32, is internally threaded, as at 34, and providedwith a seat 36 for receiving a conventional air core valve38 for opening and closing the central bores of the housing. The end of the valve housing, opposite its tip 32, is externally threaded for removably receiving adust cap, or the like, when the service valve is not in use.
OPERATION In operation the bushing 22 is assembled with the connector 14, as described thereinabove, at the time of manufacture. The purpose of the tapered seat, forming the inner limit of thecounterbore, is to bottom up or stop the movement of the housing tip 32 into the line 16, as presently explained, and prevent a partial collapse of the wall of the line 16, as by a workman threadedly engaging the housing 12 with the bushing 22 further than is necessary to pierce the wall of the line 16. The connector assembly may be placed on and soldered to refrigerant lines, such as the line 16 to be tapped, at a location convenient for servicing a refrigerant system, at the time of manufactureor, in the event line tapping service valve connectors have not been secured to the refrigerant lines at the time of manufacture of a sealed refrigerant system, the connector assembly is supplied to refrigerant service personnel with the air valve core equipped housing 12. The serviceman places the connector assembly upon the line 16 to be tapped and makes a soldered connection, as described hereinabove. it should be noted that this soldered connection between the connector legs 18 and line 16 need not be fluid tight for the reason presently explained, however, the connection between the connector 14 and the line 16 must be sufficiently strong to permit the line piercing action, as described hereinbelow.
The valve housing 12 is positioned so that its piercing tip 32 enters the bushing so that the bushing threads 24 engages the housing threads 30. A wrench. not shown, may-be used on the housing head 28 to fully threadedly engage the housing with the bushing which. by the rotation of the housing about its longitudinal axis, forces the housing tip 32 through the wall of the line 16 and forms a seal therewith. Further, a resilient washer or gasket 42 may be interposed between the housing head 28 and adjacent end of the bushing and connector, if desired. The housing bore 26 is then in communication with the bore of the line 16 so that refrigerant gas may be added to or removed from the line 16 through the air core valve 38.
Obviously the invention is susceptible to changes or alterations without defeating its practicability, therefore, I do not wish to be confined to the preferred embodiment shown in the drawings and describedherein.
1. A self-tapping service valve for a tubular line, comprising:
a generally cylindrical centrally bored housing having wrench flats intermediate its ends and having a diametrically reduced periphery at one end portion terminating in a truncated conical-shaped line piercing tip, said housing having external threads extending be tween said wrench flats and said tip,
said housing having a valve seat formed on the wall defining its bore in its end portion opposite said tip;
an air valve sealing with the valve seat;
a tubular member having one end portion transversely bifurcated for forming a U-shaped slot having a bight portion formed on a radius substantially the same as the outside radius of a line to be tapped and defining a pair of legs straddling a line to be tapped, said tubular member having a wall thickness substantially equal with respect to the wall thickness of a line to be tapped; and, a centrally bored, counterbored and internally threaded bushing coaxially soldered within the end portion of said tubular member opposite its bifurcated end, said bushing having a length not greater than the spacing between the tubular member bight portion and its end opposite its legs,
said bushing having an annular seat facing toward its threaded counterbore.
2. A tubular line service valve, comprising:
a connector including a tubular member having a relatively thin wall when compared with its diameter,
said connector having a transverse U-shaped slot in one endportion forming an arcuate surface substantially the same as the outside radius of a line to be tapped and defining a pair of legs having a length not greater than the diameter of a line to be tapped and being adapted to straddle and be secured to a line to be tapped;
centrally bored, counterbored and internally threaded bushing coaxially soldered within the end.
portion of said tubular member opposite its U- shaped slot,
said bushing having a length not greater than the spacing between the U-shaped slot and the end of said tubular member opposite its legs.
said bushing having an annular seat facing toward its threaded counterbore: and.
line piercing means coaxially received by said bushing.
having external threads adjacent said tip; and,
an air valve for opening and closin housing.
g the bore of said