US2783298A

US2783298A - Cable-anchoring and sealing device

Info

Publication number: US2783298A
Application number: US176806A
Authority: US
Inventors: Raymond R Brown; Cecil L Brownlow
Original assignee: Phillips Petroleum Co
Current assignee: Phillips Petroleum Co
Priority date: 1950-07-31
Filing date: 1950-07-31
Publication date: 1957-02-26
Anticipated expiration: 1974-02-26

Description

F b 2 1957 R. R. BROWN ETAL 2,783,298

CABLE-ANCHORING AND SEALING DEVICE Filed July 51, 1950 42 2 as H I .O.- it! H l INVENTORS.

. R. R. BROWN 8 C. L. BROWNLOW 170.3. I Y u A ORN 5 CABLE-ANCHORING AND SEALING DEVICE Raymond R. Brown and Cecil L. Brownlow, Bartlesville,

Okla, assignors to Phillips Petroleum Company, a corporation of Delaware Application July 31, 1950, Serial No. 176,806

3 Claims. (Cl. 174-59) This invention relates to seismometers. In one specific aspect it relates to a seismometer case cover embodying a cable-anchoring and sealing unit of novel design.

Heretofore, considerable difficulty has been experienced in providing electrical connections to seismometer units. Seismometers are delicate instruments which, when used in the field, are mounted in heavy metal cases to withstand considerable abuse and rough handling. The case must be so constructed so as to permit planting of the seismometer in the earth which is ordinarily accomplished by securing a thrust transmitting coupling to the seismometer cover, this coupling receiving a rod by which the seismometer case is pushed a short distance into .the earth or lowered into a shallow drill hole and anchored at the bottom of the hole. To facilitate this planting, an elongated rod or a conical nose is detachably secured to the lower end of the cover to facilitate insertion of the case into the earth. After the seismometer has been planted, the coupling and rod are removed and the seismometer is used to measure reflected or refracted waves incident thereupon. The seismometer cover is' also provided with a fastening device to retain a chain or rope by which the seismometer can be removed from its planted position after the seismic exploration operation is completed. This device ordinarily takes the form of a clevis which fits into two diametrically opposite openings forming opposite ends of a single hole in the cover, the clevis, in turn, being secured to a rope or chain which extends above the surface of the ground. i

In addition to the aforementioned requirements, an electrical cable incorporating the electrical conductors for the seismometer must pass through the cover and there must be a sealed joint at the point onentrance of the cable to prevent moisture or water from entering the cover and injuring the delicate parts of the seismometer. The cable-anchoring device must be of rugged construction to withstand abuse and rough handling of field personnel, it must not interfere with the planting or lifting appliances, and it must not protrude beyond the sides of the seismometer case so as to prevent twisting or damage thereto through contactof the cable with the sides of the hole in which the seismometer is planted.

It is an object of this invention to provide a seismometer case and cover which adequately fulfills the aforementioned exacting requirements.

It is a still further object to provide a cable-anchoring device which is of rugged construction'and does not interfere with the planting or raising of the seismometer.

It is'a still further object to provide a cable-anchoring device so oriented that the cable does not extend beyond the sides of the seismometer case and in which the cable itself is, although ordinarily securely anchored, readily detachable for replacement or repair.

Various other objects, advantages and features of the invention will become apparent from the following detailed description taken in conjunction with the accompanying drawings, in which: I

Figure l'is a vertical sectional view of a seismometer incorporating the novel cable-anchoring and securing device;

Figure 2 is a front elevational view, on a reduced scale, of the cover-case unit of Figure 1 with the planting coupling and rod in place; and

Figure 3 is a vertical sectional view of a modified cable-anchoring and sealing device.

Referring now to-Figure 1, a generally cylindrical metal casing 10 has a frusto-conical nose 11 formed integrally with the lower end thereof to form a casing or housing for a seismometer 12 mounted therein, a clamping ring 13 secured to an interior threaded portion 14 of the casing forcing the seismometer into rigid engagement with the casing, the ring being held in position by a set screw 15. A detachable conical nose 15a is secured to the lower end of portion 11 to facilitate planting of the seismometer.

A metal cover 16 is secured to the casing 10 as by screw threads 17 and an annular gasket 18 of resilient material is provided to seal the joints between the case and cover. The cover includes an enlarged lower section 26 merging into a frusto-conical section 21 defining a slanting surface 22 which is inclined with respect to the axis of the cover. The frusto-conical section 21, in turn, merges into an upper section 23 of reduced diameter as compared with that of the lower section 20. For purposes of planting the seismometer, a coupling 25 can be seated upon a threaded connection 25a, this coupling being provided with a threaded plug 26 for receiving a planting rod 27.

It will be evident that the conical portion 11, 15a can be pushed a short distance into the ground or anchored at the bottom of a shallowauger hole or other drill hole by pressure applied through the rod 27. Once the seismometer has been planted in this manner, the rod 27 and coupling 25 can be removed simply by lifting them clear of the seismometer cover.

In order to permit removal of the seismometer from a hole after a seismic exploration operation has been com pleted, the cover is provided with a pair of diametrically opposite openings forming a part of a hole 31 which openings receive a clevis 32, the clevis, in turn, having a chain 32a secured thereto to enable the seismometer to be readily lifted from its planted position. In Figure 2, the nose 15a is replaced by a long rod 15b having a blunt nose 15c to enable the nose to be pushed into the mud and firmly anchored therein.

In accordance with the invention, a cable 33' incorporating two or more electrical leads 34 extends through the cover and is secured thereto by a novel cable-anchoring and sealing device 35. This device is received within .an opening 36 in the coventhe axis of the opening being perpendicular to the inclined surface 22 and consisting of an inner portion 37 of reduced diameter, and an enlarged threaded outer portion 38 which define an interior shoulder 39. The cable 33 has, adjacent its end, an enlarged annular portion 40 of resilient material which is seated upon the shoulder 39. The terminal part of the cable extends through the reduced portion 37 of the passage to the seismometer unit 12.

An annular washer 41 is seated upon the enlarged cable portion 40, the cable and washer being rounded in a, complementary manner so that these parts are disposed in interfitting relationship. A threaded clamping nut 42 encircles the cable 33 and this nut, when tightened in the threaded outer portion 38 of passage 36, bears against the washer 41 and forces the enlarged portion 40 of the cable into sealing engagement with the shoulder 39, thus securely anchoring the cable inrposition upon the cover and preventing entrance of moisture or water through the opening 36 to the delicate parts of the seismometer.

It is a feature of the invention that the cable-anchoring and sealing device 35 is positioned upon the inclined surface 22. As a result, the cable enters the cover at a position spaced inwardly from the walls of casing so that it does not scrape against the sides of the planting hole as the seismometer unit is lowered into the earth. Moreover, the positioning of the anchoring device prevents the cable from interfering with the coupling 25 and planting rod 27 together with the chain 32a and its associated fastening device.

In Figure 1, the anchoring device may be released simply by unscrewing nut 42, but, in order to replace the cable, it is necessary to disconnect leads 34 from the seismometer 12, which, of course, involves removal of the cap and lock ring 13. In Figure 3, I have disclosed a structure wherein the cable may be readily removed without unsoldering the conductors or removing the seismometer cover, parts similar to those already described being indicated by like reference numerals in this modification.

Referring now to Figure 3, a cable 33a incorporating conductors 34a terminates in a enlarged portion 40a of resilient material which is provided with a plurality of sockets 44, one for each conductor 34a. The washer 41 and nut 42 are adapted to apply pressure to the enlarged portion 40a in the same manner as described in connection with Figure 1. An integral enlarged portion 46 of a cable 46a is seated against the shoulder 39 and provided with a plurality of plugs 47, one such plug fitting into each of the sockets 44. This portion 46 can be considered to be a part of shoulder 39. The plugs, in turn, are connected to conducors 48, respectively, which lead to the seismometer unit 12 in the same manner as the condoctors 34 of Figure 1.

It will be evident that tightening of the nut 42 transmits pressure through washer '41'to force the enlarged resilient portion 40a into sealing engagement with the enlarged portion 46 which, in turn, is forced into sealing engagement with the shoulder. This produces a positive anchoring and sealing of the cable as in the structure of Figure 1. When the nut 42 is loosened, it will be evident that the sockets 44 may be readily detached from the plugs 47 with the result that the cable can be completely removed and disconnected without removing the cover 16 and without unsoldering the leads 48 connected to the seismorneter unit 12. This feature is valuable in practical field work, since the cables oftentimes are broken or damaged outside the seismometer case. When the cable is so removed, cap 42 and washer 41 can be reinserted and forced into engagement with cable portion 46, thus sealing the interior of the casing.

While the invention has been described in connection with present, preferred embodiments thereof, it is to be understood that this description is illustrative only and is not intended to limit the invention, the scope of which is defined by the appended claims.

We claim:

1. In combination, a metal cover, an elongated housing threaded to said cover to define a pressure-tight vessel, said cover having a flat central portion generally perpendicular to the axis of said elongated housing, and a surface inclined tosaid axis connecting said central portion to the periphery of the cover, said inclined surface having a bore formed therein extending through said cover with its axis generally perpendicular to said inclined surface, said bore having a relatively small interior portion and a relatively large threaded outer portion, thereby to define an internal shoulder, a cable extending into said opening, said cable having an integral enlarged portion of resilient material positioned within the outer portion of said bore with one end of said enlarged portion engaging said shoulder, a washer encircling said cable and engaging the other end of said enlarged portion, an annular threaded nut encircling said cable and bearing against said washer, said nut fitting within the threaded outer portion of said passage, whereby tightening of said nut forces said resilient enlarged portion of the cable into sealing engagement with said shoulder, and connecting means on. the flat central portion of said cover, said cable, by virtue of said inclined surface, being confined within an extension of the outer surface of said vessel, thereby to prevent damage to the cable as the vessel is raised and lowered in a bore hole.

2. The structure of claim 1 wherein said enlarged portion directly engages said shoulder, and cable incorporates a pair of integral conductors extending from the interior of the vessel to the exterior thereof.

3. The structure of claim 1 wherein a second cable extends from the interior of said vessel to said shoulder, said second cable having an enlarged portion engaging said shoulder and the enlarged portion of said first-mentioned cable bearing against said enlarged portion engaging said shoulder, and said first cable having sockets fitting into plugs extending from said second cable.

References Cited in the file of this patent UNITED STATES PATENTS 1,200,368 Klug Oct. 3, 1916 1,858,816 Burkhardt May 17, 1932 1,974,422 Hayes Sept. 25, 1934 2,275,762 Horton Mar. 10, 1942 2,449,085 Peterson Sept. 14, 1948 2,477,172 Brownlow July 26, 1949 2,568,680 Frowe Sept. 18, 1951 2,568,851 Flnde Sept. 25, 1951 FOREIGN PATENTS 632,798 Germany June 28, 1934 494,510 Great Britain Oct. 24, 1938