GB2083153A - Slip jam nut conduit connection - Google Patents

Abstract

A slip jam nut conduit connection is provided that allows the connection to be used readily with either of two conduits of different outside diameters. The jam washer 16 has two annular components 38, 40 so that when the components are interfitted the slip jam nut connection can be used with a conduit of one size, as shown and when the annular components 38 is removed and discarded, the slip jam nut connection can be used with a conduit of a larger size. <IMAGE>

Description

SPECIFICATION Slip jam nut connection and jam washer Technical field The present invention relates to fittings utilized by the plumbing industry, and especially to slip jam nut connections.

Background art It is conventional practice in the plumbing industry to utilize slip jam nut fittings for making connections in plumbing systems. A variety of common sizes of slip jam nut connections are used, such as, for example, 1 1/4"O.D.andl 1/2"O.D.,andforvirtually every instance that a need exists for the smaller connection, a similar need exists elsewhere in the plumbing system for the larger connection. As a result, inventories of conventional slip jam nut fittings for both sizes of connections are maintained.

The conventional slip jam nut fittings include an externally threaded adapter, a slip nut, and a jam washer. Frequently, the adapters and slip nuts that are used in these fittings can be the same size for similar connections, such as the aforesaid 1 114" O.D.

and the 11/2" O.D. connections, but the jam washers that are used in the two connections necessarily are different in size. Thus, when using conventional fittings, the duplication of parts that occurs results in greater inventories being maintained than is desirable in order to assure adequate supplies being available for installing a plumbing system. The object of the present invention is to overcome inadequacies of this nature and to provide an improved jam washer which can be used in slip jam nut fittings in a manner to reduce the number of fittings to be inventoried.

Summary of the invention The present invention provides a unique jam washer for use in a slip jam nut connection and which is an assembly of at least first and second interfitting annular members, the annular members being separable so that (1) when interfitted they will function as a jam washer in a connection for providing a seal against a conduit of one radius, and (2) when separated the first annular member may be discarded and the second annular member will function alone as the jam washer for providing a seal against a conduit of a larger diameter.Thus, by virtue of the unique construction provided, the jam washer can be used together with the other parts of a slip jam nut connection so as to enable the worker in the field to employ the same slip jam nut connection for making a joint either with a conduit of one dimension or with a similar conduit of a larger dimension. In this manner the inventory of parts needed for installing a plumbing system can be kept at a minimum.

Accordingly, it is the primary object of the present invention to provide an improved slip jam nut connection and jam washer.

Other objects of this invention will appear in the following description and appended claims, reference being had to the accompanying drawings forming a part of this specification wherein like reference characters designate corresponding parts in the several views.

Description of the drawing Figure 1 is an exploded perspective view of a slip jam nut connection that embodies one form of the present invention and showing in phantom lines fragments of conduits which can be connected by the slip jam nut connection; Figure2 is an enlarged axial section of the slip jam nut connection showing a conduit of one outside diameter secured in place; Figure 3 is a similar axial section of the slip jam nut connection showing the manner of securing a second conduit of larger outside diameter after one of the annular members of the jam washer has been removed; and Figure 4 is an enlarged perspective view, partly in section, showing the jam washer with the first and second interfitting annular members in their assembled positions.

Description of the preferred embodiment Before explaining the present invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and arrangement of parts illustrated in the accompanying drawings, since the invention is capable of other embodiments and of being practiced or carried out in various ways. Also, it is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation.

Referring now to the drawings, the invention will be described in greater detail. The slip jam nut connection 10 embodying the present invention includes the externally threaded adapter 12, a slip nut 14, and a jam washer 16.

The adapter 12 and slip nut 14 are conventional in construction. The adapter is externally threaded at 18 and the slip nut 12 is internally threaded at 20 for making a threaded connection. As can be seen in the drawings, the slip nut is internally threaded at one end and has a radially inwardly directed flange 22 at the other end which provides a seat at 24 on which the jam washer 16 can be seated. The adapter 12 has a beveled end 26 for engagement with the jam washer to urge the latter radially inwardly into sealed engagement with the outer wall of a conduit 28 in the conventional manner.

The unique jam washer 16 has a radially extending flat end wall 30 and an annular wedge portion 32 extending axially from the flat end wall 30. The annular wedge portion 32 has an inner generally cylindrical wall 34 for making sealing engagement with a conduit, such as the conduit 28, the latter having a fixed outside diameter that corresponds generally to the internal diameter of the cylindrical wall 34.

As shown best in Figures 2 and 4, the jam washer 16 has a radial cross section of essentially a right triangle with one side being part of the cylindrical wall 34, the other side being part of the end wall 30, and the hypotenuse of the triangle being part of the wedge surface 36. The jam washer is an assembly of a first interfitting annular member 38 and a second interfitting annular member 4. The second annular member 40 has a radial cross section that is smaller and essentially a similar right triangle to that of the complete jam washer 16, and the hypotenuse of the second annular member defines and coincides with the hypotenuse of the jam washer 16. The first annular member includes a cylindrical sleeve that defines the radially inner wall of the washer 16 and a flange extending radially outwardly from one end of the sleeve which defines the flat end of the washer 16.The second annular member 40 has a cylindrical inner surface 42 fitted against the radially outer surface of the cylindrical sleeve of the first interfitting member 38.

The interfitting members 38 and 40 are interfitted so that when they are in their interfitted positions, they can be used in conjunction with the adapter 12 and slip nut 14 with a conduit 28, which has a fixed outside diameter, such as 11/4", and when the slip jam nut connection is secure on the conduit 28 by turning the jam nut 14 on the adapter 12, the beveled end 26 of the adapter 12 will engage the wedge portion 36 to urge the jam washer sealingly into engagement with the outer wall of the conduit 28.

If it is desired to use the same slip jam nut connection 10 to make a joint with a conduit 44 of larger outside diameter, such as one having an outside diameter of 11/2", the interfitting members 38 and 40 will be separated, and the interfitting member 38 can be discarded. The slip jam nut connection will then be assembled in the conventional manner shown in Figure 3, and when the jam nut 14 is threadedly advanced onto the adapter 12, a sealed joint will be provided between the second annular member 40 and the outer surface of the conduit 44.

Preferably, the assembled components of the jam washer 16 will be manufactured from a suitable thermoplastic material such as polyethylene, or a similar compressible material. Also, the cylindrical sleeve of the first annular member 38 will be dimensioned in wall thickness an amount so that the difference in inside diameters of the first and second annular members 38 and 40 corresponds to the difference in outside diameters between two standard sizes of conduits, such as conduits 28 and 44.

Claims (9)

1. A slip jam nut connection comprising an externally threaded adapter with a beveled end for engagement with the wedge portion of a jam washer, a slip nut for fitting on a conduit and having an internally threaded portion at one end for making a threaded connection with said adapter and a radially inwardly directed flange at the other end providing a seat for said jam washer to urge the wedge portion of said jam washer against said beveled end so as to jam the wedge portion radially inwardly into sealing engagement against a conduit fitted in the slip nut, and a jam washer having a radially extending flat end wall seated on said inwardly directed flange and an annular wedge portion extending axially from the flat end wall for engagement by said beveled edge, said annular wedge portion having an inner generally cylindrical wall for making the sealing engagement with a conduit that extends into the jam nut connection, characterized in that said washer is an assembly of at least first and second interfitting annular members, said annular members being separable so that (1) when interfitted they will function as a jam washer in the connection for providing a seal against a conduit of one radius, and (2) when separated the first annular member will function alone as the jam washer for the same adapter and slip nut for providing a seal against a conduit of a larger diameter.

2. A slip jam nut connection according to claim 1, characterized in that said jam washer has a radial cross section of essentially a right triangle with one side being part of said cylindrical wall, the other side being part of said end wall and the hypotenuse being part of the wedge surface engageable by said beveled end, and said second annular member has a radial cross section that is smaller and essentially a similar right triangle to that of said jam washer, and the hypotenuse of said second annular member defines the hypotenuse of said jam washer.

3. A slip jam nut connection according to claim 2, characterized in that the radial dimension between corresponding cylindrical walls of said jam washer and said second annular member is a preselected dimension equal to the difference in radial dimensions of two conventional conduits.

4. A slip jam nut connection having a threaded adapter with a beveled end for radially inwardly urging the wedge portion of a jam washer, a slip nut for fitting on a conduit and having a threaded portion at one end for threaded connection to said adapter and a radially inwardly directed flange at the other end for providing a seat for said washer to urge said washer against said beveled end, and a washer having a flat end wall seated on said inwardly directed flange and an annular wedge extending axially from the flat end wall for engagement with said beveled edge, said annular wedge having an inner generally cylindrical wall for sealing engage ment with a conduit that extends into the jam nut connection, characterized in that said washer is an assembly of at least two interfitting annular mem bers, the first annular member including a cylindrical sleeve defining the radially inner wall of said washer and having a flange extending radially outwardly from one end of said sleeve, said flange defining said flat end of the washer, and said second annular member having a cylindrical inner surface fitted against the radially outer surface of said cylindrical sleeve, a flat radially directed end seated on said flat end wall and a beveled surface extending between said cylindrical inner surface and said flat radially directed end against which said beveled end of said adapter can be urged, said annular members being separable so that when interfitted they will function as a jam washer in the connection providing a seal against a conduit of one diameter, and when sepa rated the second annular member will function as the jam washer for the same adapter and slip nut for providing a seal againt a conduit of a larger dia meter.

5. A jam washer having a radially extending flat end wall and an annular wedge portion extending axially from the flat end wall, said annular wedge portion having an inner generally cylindrical wall for making sealing engagement with a conduit of a predetermined radius, characterized in that said jam washer is an assembly of at least first and second interfitting annular members, said annular members being separable so that (1) when interfitted they will function as a jam washer in a connection for providing a seal against said conduit of one radius, and (2) when separated the first annular member may be discarded and the second annular member will function alone as the jam washer for providing a seal against a conduit of a larger diameter.

6. A jam washer according to claim 5, characterized in that said jam washer has a radial cross section of essentially a right triangle with one side being part of said cylindrical wall, the other side being part of said end wall and the hypotenuse being part of the wedge surface, and said second annular member has a radial cross section that is smaller and essentially a similar right triangle to that of said jam washer, and the hypotenuse of said second annular member defines the hypotenuse of said jam washer.

7. A jam washer connection according to claim 6, characterized in that the radial dimension between corresponding cylindrical walls of said jam washer and said second annular member is a preselected dimension equal to the difference in radial dimensions of two conventional conduits.

8. A slip jam nut connection constructed and arranged to operate substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.

9. A jam washer constructed and arranged substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.