US2724736A - Spring type strain-relief bushing - Google Patents

Spring type strain-relief bushing Download PDF

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US2724736A
US2724736A US339420A US33942053A US2724736A US 2724736 A US2724736 A US 2724736A US 339420 A US339420 A US 339420A US 33942053 A US33942053 A US 33942053A US 2724736 A US2724736 A US 2724736A
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Prior art keywords
bushing
strain
cable
conductor
relief
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US339420A
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Jr Ferdinand Klumpp
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B17/00—Insulators or insulating bodies characterised by their form
    • H01B17/56—Insulating bodies
    • H01B17/58—Tubes, sleeves, beads, or bobbins through which the conductor passes
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01R—ELECTRICALLY-CONDUCTIVE CONNECTIONS; STRUCTURAL ASSOCIATIONS OF A PLURALITY OF MUTUALLY-INSULATED ELECTRICAL CONNECTING ELEMENTS; COUPLING DEVICES; CURRENT COLLECTORS
    • H01R13/00—Details of coupling devices of the kinds covered by groups H01R12/70 or H01R24/00 - H01R33/00
    • H01R13/58—Means for relieving strain on wire connection, e.g. cord grip, for avoiding loosening of connections between wires and terminals within a coupling device terminating a cable
    • H01R13/5804—Means for relieving strain on wire connection, e.g. cord grip, for avoiding loosening of connections between wires and terminals within a coupling device terminating a cable comprising a separate cable clamping part
    • H01R13/5816—Means for relieving strain on wire connection, e.g. cord grip, for avoiding loosening of connections between wires and terminals within a coupling device terminating a cable comprising a separate cable clamping part for cables passing through an aperture in a housing wall, the separate part being captured between cable and contour of aperture

Definitions

  • strainrelief structure in which the main body thereof is formed with an elongated integral part formed like a spring, it being understood that this main part of the strain-relief device is made of suitable insulating material such as nylon.
  • Figure 1 is a plan view of the strain-relief device applied to a cable and showing one position in broken lines which the spring end may take during its use.
  • Figure 2 is a side view of Figure 1.
  • Figure 3 is a part sectional and part elevational view on the center line of Figure 1.
  • Figure 4 is a sectional view on the line 4--4 of Figure 1.
  • Figure 5 is a view of the main part of the strain-relief device without the grip lock, the position of the cable being indicated in broken lines.
  • Figure 6 is a plan view of the inner portion of the grip lock.
  • Figure 7 is a side view of the grip lock.
  • Figure 8 is a section on the line 88 of Figure 7.
  • Figure 9 is a view on the line 9-9 of Figure 1.
  • Figure 10 is a view on the line 1010 of Figure 2.
  • drawings 1 is the body or main part of the strain-relief structure. Extending longitudinally from the body portion 1 are a plurality of spaced parts 2 corresponding to the convolutions of a spring. These convolutions terminate in a circular flange 3. I have found that where the convolutions 2 are arranged in three parts resembling screw threads, the flexibility of a suitable molded material, such as nylon, will give excellent flexibility so that the cable may be bent at a considerable angle without injuring it or the turns 2.
  • the body portion 1 has a flange 4 which is adapted to engage a mounting plate 5 as shown in Figures 1 and 2.
  • hub 6 Projecting from the flange 4 is a hub 6 having flat surfaces on opposite sides ending in tapered surfaces 7 on "ice each side for assistance in assembling the strain-relief device into its mounting plate 5.
  • the interior part of hub 6 has grooves 8 extending downwardly toward a bottom recess 9. These grooves 8 are adapted to receive fingers 10 which project from the key member 11.
  • a circular portion 12 that'is adapt ed to engage the cable C when the key 11 is forced into locking position by pushing the strain-relief device into a cooperating hole in the mounting plate 5.
  • the key has an arcuately shaped groove 13 on its outer surface to engage the mounting plate 5 and to hold the key in its locking position, forcing the cable into the recess 9 as shown in Figure 3.
  • a strain relief bushing having a main portion to receive a cable or conductor and a locking key slidably carried by the main portion which has an integral extension composed of spaced parts resembling and acting as a spring as and for the purpose described.
  • a strain relief bushing having a main portion and a locking key slidably carried by and at right angles to the horizontal axis of said main portion which has an integral extension composed of spaced parts resembling and acting as a spring and having an interior diameter 10 receive a cable or conductor.
  • a strain relief bushing of suitable insulating material for holding an electrical conductor in a mounting plate hole said bushing having a body portion with a flange to engage a mounting plate, said body portion having a hollow integral extension at its other end, said extension being composed of spaced resilient parts resembling a spring and serving as a flexible support for said conductor, said body portion having a transverse opening through one side of its wall at the end opposite said spring portion, the body portion having a recess opposite said opening and below the main hollow part of the bushing and a grip-key positioned in said opening and adapted to be engaged by said plate, when the bushing is forced into the plate hole, to bend the conductor into said recess and lock it securely in the bushing.
  • a strain relief bushing as set forth in claim 3 further defined in that said spring-like end is formed by a plurality of spirally arranged parts terminating in a collar at the outer end for receiving a conductor.
  • a strain relief bushing as set forth in claim 3 further defined in that said spring-like end is formed by three spirally arranged parts which terminate in an integral collar to receive a conductor.
  • a mounting plate having a hole therein to receive a strain-relief bushing of suitable insulating material, the bushing being composed of two parts to grip an electrical conductor or cable placed between them, one part having a recess therein while the other part is slidable as a whole toward a longitudinal axis of said one part, said slidable part having an arcuately formed projection for engaging said conductor or cable, each part having at least a slight tapered end to assist in entering the parts into said hole, the two parts being forced toward each other by the wall of the hole so said projection will force the conductor or cable downwardly into said recess, both parts having co-operative arcuate grooves to lock the parts to the mounting plate, said part having the recess therein having an integral circular ex Patented Nov. 22, 5
  • a bushing of strong insulating material to fit said hole, the. bushing having a transverse side opening at one end with a recess opposite said opening and a passageway spaced longitudinally away from said recess, said passageway terminating in an integral elongated circular springlike formed section of insulating material through which a cable or conductor may pass through the bushing, a locking key of strong insulating material transversely carried by said bushing opposite said recess and adapted to be. moved toward said recess to grip the conductor and force it into said recess and means on the bushing and key to lock the two of them in the plate hole.

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Description

Nov. 22, 1955 F. KLUMPP, JR 2,724,736
SPRING TYPE STRAIN-RELIEF BUSHING Filed Feb. 27, 1955 %Wz;@ Eat b24271] warm ya c771 United States Patent SPRING TYPE STRAIN-RELIEF BUSHING Ferdinand Klumpp, Jr., Union, N. J.
Application February 27, 1953, Serial No. 339,420
7 Claims. (Cl. 174-153) In my Patent 2,424,758, July 29, 1947, I have shown and described a self-locking strain-relief bushing for the purpose of securing an electrical conductor or cable in the bushing when the same is moved into position into a support of the plate type. I have also made a strainrelief device in which one end of a circular elongated metal spring is mounted. The spring embraces a cable or conductor coming to the strain-relief device for the purpose of taking much of the strain off the cable or conductor if the same is bent at a substantial angle closely adjacent the strain-relief device. It has been found from practice that in some uses the metallic spring will wear into the insulation around the cable or conductor and may cause trouble such as a short circuit.
To overcome this trouble I have developed a strainrelief structure in which the main body thereof is formed with an elongated integral part formed like a spring, it being understood that this main part of the strain-relief device is made of suitable insulating material such as nylon.
By the construction to be hereinafter described I have eliminated the metal spring entirely and have simplified the key used for locking the cable or conductor in place within the holder or body portion of the strainrelief device.
In the drawing:
Figure 1 is a plan view of the strain-relief device applied to a cable and showing one position in broken lines which the spring end may take during its use.
Figure 2 is a side view of Figure 1.
Figure 3 is a part sectional and part elevational view on the center line of Figure 1.
Figure 4 is a sectional view on the line 4--4 of Figure 1.
Figure 5 is a view of the main part of the strain-relief device without the grip lock, the position of the cable being indicated in broken lines.
Figure 6 is a plan view of the inner portion of the grip lock.
Figure 7 is a side view of the grip lock.
Figure 8 is a section on the line 88 of Figure 7.
Figure 9 is a view on the line 9-9 of Figure 1.
Figure 10 is a view on the line 1010 of Figure 2.
In the drawing the various views are made full size of the working device or model. In drawings 1 is the body or main part of the strain-relief structure. Extending longitudinally from the body portion 1 are a plurality of spaced parts 2 corresponding to the convolutions of a spring. These convolutions terminate in a circular flange 3. I have found that where the convolutions 2 are arranged in three parts resembling screw threads, the flexibility of a suitable molded material, such as nylon, will give excellent flexibility so that the cable may be bent at a considerable angle without injuring it or the turns 2. The body portion 1 has a flange 4 which is adapted to engage a mounting plate 5 as shown in Figures 1 and 2. Projecting from the flange 4 is a hub 6 having flat surfaces on opposite sides ending in tapered surfaces 7 on "ice each side for assistance in assembling the strain-relief device into its mounting plate 5. The interior part of hub 6 has grooves 8 extending downwardly toward a bottom recess 9. These grooves 8 are adapted to receive fingers 10 which project from the key member 11. Between the fingers 10 is a circular portion 12 that'is adapt ed to engage the cable C when the key 11 is forced into locking position by pushing the strain-relief device into a cooperating hole in the mounting plate 5. The key has an arcuately shaped groove 13 on its outer surface to engage the mounting plate 5 and to hold the key in its locking position, forcing the cable into the recess 9 as shown in Figure 3. After the cable or conductor has been inserted through the spaced parts, 2 into the body portion 1, the key member 11 is placed into position and then the assembled device is forced into the support plate 5 which causes the key 11 to move into the locking position as shown.
From the foregoing it will be seen that I have provided a two piece strain'relief structure in a new and novel manner.
Having thus described my invention, what I claim is:
l. A strain relief bushing having a main portion to receive a cable or conductor and a locking key slidably carried by the main portion which has an integral extension composed of spaced parts resembling and acting as a spring as and for the purpose described.
2. A strain relief bushing having a main portion and a locking key slidably carried by and at right angles to the horizontal axis of said main portion which has an integral extension composed of spaced parts resembling and acting as a spring and having an interior diameter 10 receive a cable or conductor.
3. A strain relief bushing of suitable insulating material for holding an electrical conductor in a mounting plate hole, said bushing having a body portion with a flange to engage a mounting plate, said body portion having a hollow integral extension at its other end, said extension being composed of spaced resilient parts resembling a spring and serving as a flexible support for said conductor, said body portion having a transverse opening through one side of its wall at the end opposite said spring portion, the body portion having a recess opposite said opening and below the main hollow part of the bushing and a grip-key positioned in said opening and adapted to be engaged by said plate, when the bushing is forced into the plate hole, to bend the conductor into said recess and lock it securely in the bushing.
4. A strain relief bushing as set forth in claim 3 further defined in that said spring-like end is formed by a plurality of spirally arranged parts terminating in a collar at the outer end for receiving a conductor.
5. A strain relief bushing as set forth in claim 3 further defined in that said spring-like end is formed by three spirally arranged parts which terminate in an integral collar to receive a conductor.
6. The combination of a mounting plate having a hole therein to receive a strain-relief bushing of suitable insulating material, the bushing being composed of two parts to grip an electrical conductor or cable placed between them, one part having a recess therein while the other part is slidable as a whole toward a longitudinal axis of said one part, said slidable part having an arcuately formed projection for engaging said conductor or cable, each part having at least a slight tapered end to assist in entering the parts into said hole, the two parts being forced toward each other by the wall of the hole so said projection will force the conductor or cable downwardly into said recess, both parts having co-operative arcuate grooves to lock the parts to the mounting plate, said part having the recess therein having an integral circular ex Patented Nov. 22, 5
tension composed of spaced parts resembling and acting as a spring as and for the purpose described.
7. In combination with a mounting plate having a hole therein to non-rotatably receive a strain-relief bushing, a bushing of strong insulating material to fit said hole, the. bushing having a transverse side opening at one end with a recess opposite said opening and a passageway spaced longitudinally away from said recess, said passageway terminating in an integral elongated circular springlike formed section of insulating material through which a cable or conductor may pass through the bushing, a locking key of strong insulating material transversely carried by said bushing opposite said recess and adapted to be. moved toward said recess to grip the conductor and force it into said recess and means on the bushing and key to lock the two of them in the plate hole.
References Cited in the file of this patent UNITED STATES PATENTS McCatchie Apr. 29, 1924 Preston Mar. 6, 1934 Klumpp July 29, 1947 Reder June 14, 1949 Hultgren Aug. 7, 1951 FOREIGN PATENTS France Jan. 25, 1932 (First addition to No; 695,525)
US339420A 1953-02-27 1953-02-27 Spring type strain-relief bushing Expired - Lifetime US2724736A (en)

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Cited By (22)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2820209A (en) * 1956-02-28 1958-01-14 Whitso Inc Insulated electrical terminal
US2922836A (en) * 1956-02-20 1960-01-26 Chrysler Corp Grommet
US3156514A (en) * 1961-11-21 1964-11-10 Hi Shear Corp Connector
US3258234A (en) * 1963-05-28 1966-06-28 United Carr Inc Strain-relief device
US3749818A (en) * 1971-09-30 1973-07-31 Heyman Mfg Co Electric cord stress relief combined with a strain relief grommet
DE2714225A1 (en) * 1976-06-17 1977-12-29 Heyman Mfg Co MOLDED FROM A DIELECTRIC PLASTIC, SELF-LOCKING BENDING AND STRAIN RELIEF SLEEVE OR SLEEVE
US4137558A (en) * 1977-01-10 1979-01-30 Robertshaw Controls Company Instrument probe assembly having continuous probe insulation
FR2552278A1 (en) * 1983-09-16 1985-03-22 Kitagawa Ind Co Ltd ELECTRIC CORD PASSING CANNON
US4632488A (en) * 1984-06-08 1986-12-30 Switchcraft, Inc. Cord strain relief device
US4734055A (en) * 1981-12-30 1988-03-29 Kitagawa Industries Co., Ltd. Cord bushing
US5375523A (en) * 1990-05-23 1994-12-27 J.E.M. Smoke Machine Company, Ltd. Pyrotechnic device
US5390272A (en) * 1993-08-31 1995-02-14 Amphenol Corporation Fiber optic cable connector with strain relief boot
US5823817A (en) * 1996-10-24 1998-10-20 Hamilton Beach/Proctor-Silex, Inc. Cord guard
US5874709A (en) * 1997-04-14 1999-02-23 Tweco Products, Inc. Strain relief assembly for welding cable
USD406428S (en) * 1997-07-02 1999-03-02 Hamilton Beach/Proctor-Silex, Inc. Cord guard
US20010049519A1 (en) * 1995-06-05 2001-12-06 Holman Thomas J. Integral hub and strain relief
US20100048051A1 (en) * 2008-02-21 2010-02-25 Melni Mark L Electrical connectors and methods of manufacturing and using same
US20110097948A1 (en) * 2008-02-21 2011-04-28 Melni Mark L Electrical connectors and methods of manufacturing and using same
WO2011056901A2 (en) 2009-11-03 2011-05-12 Mark L Melni Electrical connectors and methods of manufacturing and using same
US20140260308A1 (en) * 2013-03-13 2014-09-18 Ecoservices, Llc Rear mounted wash manifold retention system
US9703317B2 (en) 2013-03-14 2017-07-11 Biosense Webster (Israel) Ltd. Dongle with shape memory
US20190221337A1 (en) * 2018-01-15 2019-07-18 Leoni Kabel Gmbh Anti-kink device for a cable

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1492335A (en) * 1919-03-21 1924-04-29 Benjamin Electric Mfg Co Attachment device
FR695525A (en) * 1929-11-21 1930-12-17 Kabelfabrik Ag Power line with watertight traverse
FR40162E (en) * 1931-04-27 1932-06-07 Kabelfabrik Ag Power line with watertight feed-through
US1950036A (en) * 1929-05-29 1934-03-06 Black & Decker Mfg Co Cord clamp for portable electric tools
US2424758A (en) * 1945-06-14 1947-07-29 Heyman Mfg Company Strain-relief bushing
US2472986A (en) * 1946-05-23 1949-06-14 Jr Emil E Reder Cord protector and strain reliever for use with electrical connectors
US2563604A (en) * 1951-08-07 Strain belief bushing

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2563604A (en) * 1951-08-07 Strain belief bushing
US1492335A (en) * 1919-03-21 1924-04-29 Benjamin Electric Mfg Co Attachment device
US1950036A (en) * 1929-05-29 1934-03-06 Black & Decker Mfg Co Cord clamp for portable electric tools
FR695525A (en) * 1929-11-21 1930-12-17 Kabelfabrik Ag Power line with watertight traverse
FR40162E (en) * 1931-04-27 1932-06-07 Kabelfabrik Ag Power line with watertight feed-through
US2424758A (en) * 1945-06-14 1947-07-29 Heyman Mfg Company Strain-relief bushing
US2472986A (en) * 1946-05-23 1949-06-14 Jr Emil E Reder Cord protector and strain reliever for use with electrical connectors

Cited By (34)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2922836A (en) * 1956-02-20 1960-01-26 Chrysler Corp Grommet
US2820209A (en) * 1956-02-28 1958-01-14 Whitso Inc Insulated electrical terminal
US3156514A (en) * 1961-11-21 1964-11-10 Hi Shear Corp Connector
US3258234A (en) * 1963-05-28 1966-06-28 United Carr Inc Strain-relief device
US3749818A (en) * 1971-09-30 1973-07-31 Heyman Mfg Co Electric cord stress relief combined with a strain relief grommet
DE2714225A1 (en) * 1976-06-17 1977-12-29 Heyman Mfg Co MOLDED FROM A DIELECTRIC PLASTIC, SELF-LOCKING BENDING AND STRAIN RELIEF SLEEVE OR SLEEVE
US4137558A (en) * 1977-01-10 1979-01-30 Robertshaw Controls Company Instrument probe assembly having continuous probe insulation
US4734055A (en) * 1981-12-30 1988-03-29 Kitagawa Industries Co., Ltd. Cord bushing
FR2552278A1 (en) * 1983-09-16 1985-03-22 Kitagawa Ind Co Ltd ELECTRIC CORD PASSING CANNON
US4568047A (en) * 1983-09-16 1986-02-04 Kitagawa Industries Co., Ltd. Cord bushing
US4632488A (en) * 1984-06-08 1986-12-30 Switchcraft, Inc. Cord strain relief device
US5375523A (en) * 1990-05-23 1994-12-27 J.E.M. Smoke Machine Company, Ltd. Pyrotechnic device
US5390272A (en) * 1993-08-31 1995-02-14 Amphenol Corporation Fiber optic cable connector with strain relief boot
US20010049519A1 (en) * 1995-06-05 2001-12-06 Holman Thomas J. Integral hub and strain relief
US5823817A (en) * 1996-10-24 1998-10-20 Hamilton Beach/Proctor-Silex, Inc. Cord guard
US5874709A (en) * 1997-04-14 1999-02-23 Tweco Products, Inc. Strain relief assembly for welding cable
USD406428S (en) * 1997-07-02 1999-03-02 Hamilton Beach/Proctor-Silex, Inc. Cord guard
US8771000B2 (en) 2008-02-21 2014-07-08 Melni, Llc Electrical connectors and methods of manufacturing and using same
US9608346B2 (en) 2008-02-21 2017-03-28 Melni, Llc Mechanical and/or electrical connector with axial-pull apparatus and methods
US7901233B2 (en) 2008-02-21 2011-03-08 Melni Mark L Electrical connectors and methods of manufacturing and using same
US20110097948A1 (en) * 2008-02-21 2011-04-28 Melni Mark L Electrical connectors and methods of manufacturing and using same
US8066525B2 (en) 2008-02-21 2011-11-29 Melni Mark L Electrical connectors and methods of manufacturing and using same
US8246370B2 (en) 2008-02-21 2012-08-21 Melni Mark L Electrical connectors and methods of manufacturing and using same
US20100048051A1 (en) * 2008-02-21 2010-02-25 Melni Mark L Electrical connectors and methods of manufacturing and using same
US9614304B2 (en) 2008-02-21 2017-04-04 Melni, Llc Electrical connectors and methods of manufacturing and using same
US7794255B2 (en) 2008-02-21 2010-09-14 Melni Mark L Electrical connectors and methods of manufacturing and using same
WO2011056901A2 (en) 2009-11-03 2011-05-12 Mark L Melni Electrical connectors and methods of manufacturing and using same
US9212565B2 (en) * 2013-03-13 2015-12-15 Ecoservices, Llc Rear mounted wash manifold retention system
US20140260308A1 (en) * 2013-03-13 2014-09-18 Ecoservices, Llc Rear mounted wash manifold retention system
US9703317B2 (en) 2013-03-14 2017-07-11 Biosense Webster (Israel) Ltd. Dongle with shape memory
US10234897B2 (en) 2013-03-14 2019-03-19 Biosense Webster (Israel) Ltd. Catheter-based system having dongle with shape memory
US10664008B2 (en) 2013-03-14 2020-05-26 Biosense Webster (Israel) Ltd. Catheter-based system having dongle with shape memory
US20190221337A1 (en) * 2018-01-15 2019-07-18 Leoni Kabel Gmbh Anti-kink device for a cable
US11011289B2 (en) * 2018-01-15 2021-05-18 Leoni Kabel Gmbh Anti-kink device for a cable

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