US3858737A - Excavator - Google Patents

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US3858737A
US3858737A US309888A US30988872A US3858737A US 3858737 A US3858737 A US 3858737A US 309888 A US309888 A US 309888A US 30988872 A US30988872 A US 30988872A US 3858737 A US3858737 A US 3858737A
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excavator
antennae
receiver
buried metal
buried
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US309888A
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Rikizo Senoo
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    • EFIXED CONSTRUCTIONS
    • E02HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02FDREDGING; SOIL-SHIFTING
    • E02F3/00Dredgers; Soil-shifting machines
    • E02F3/04Dredgers; Soil-shifting machines mechanically-driven
    • E02F3/28Dredgers; Soil-shifting machines mechanically-driven with digging tools mounted on a dipper- or bucket-arm, i.e. there is either one arm or a pair of arms, e.g. dippers, buckets
    • E02F3/30Dredgers; Soil-shifting machines mechanically-driven with digging tools mounted on a dipper- or bucket-arm, i.e. there is either one arm or a pair of arms, e.g. dippers, buckets with a dipper-arm pivoted on a cantilever beam, i.e. boom
    • E02F3/32Dredgers; Soil-shifting machines mechanically-driven with digging tools mounted on a dipper- or bucket-arm, i.e. there is either one arm or a pair of arms, e.g. dippers, buckets with a dipper-arm pivoted on a cantilever beam, i.e. boom working downwardly and towards the machine, e.g. with backhoes
    • EFIXED CONSTRUCTIONS
    • E02HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02FDREDGING; SOIL-SHIFTING
    • E02F3/00Dredgers; Soil-shifting machines
    • E02F3/04Dredgers; Soil-shifting machines mechanically-driven
    • E02F3/28Dredgers; Soil-shifting machines mechanically-driven with digging tools mounted on a dipper- or bucket-arm, i.e. there is either one arm or a pair of arms, e.g. dippers, buckets
    • E02F3/30Dredgers; Soil-shifting machines mechanically-driven with digging tools mounted on a dipper- or bucket-arm, i.e. there is either one arm or a pair of arms, e.g. dippers, buckets with a dipper-arm pivoted on a cantilever beam, i.e. boom
    • EFIXED CONSTRUCTIONS
    • E02HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02FDREDGING; SOIL-SHIFTING
    • E02F9/00Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/24Safety devices, e.g. for preventing overload
    • E02F9/245Safety devices, e.g. for preventing overload for preventing damage to underground objects during excavation, e.g. indicating buried pipes or the like
    • EFIXED CONSTRUCTIONS
    • E02HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02FDREDGING; SOIL-SHIFTING
    • E02F9/00Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/26Indicating devices
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01VGEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS
    • G01V3/00Electric or magnetic prospecting or detecting; Measuring magnetic field characteristics of the earth, e.g. declination, deviation
    • G01V3/15Electric or magnetic prospecting or detecting; Measuring magnetic field characteristics of the earth, e.g. declination, deviation specially adapted for use during transport, e.g. by a person, vehicle or boat
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10STECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S37/00Excavating
    • Y10S37/906Visual aids and indicators for excavating tool

Definitions

  • An improved excavator which is provided with a transmitter, a receiver and antennae of a buried metal detector, being characterized in that said antennae comprise three antennae which are disposed in the bucket arm of said excavator in three dimensional perpendicular relation. and thereby the damages of buried metal facilities can be prevented.
  • the present invention relates to an improved excavator for digging the soil. Further, the invention relates to the excavator which is provided with a transmitter, a receiver and antennae of a buried metal detector being characterized in that said antennae comprise three antennae and positioned in the bucket arm of the excavator in three dimensional perpendicular relation. Still further, the invention relates to the excavator which can detect the buried metal facilities to stop the bucket arm thereof.
  • Excavators are generally employed for digging the soil in construction site, and if the public facilities such as city-water pipes, gas pipes, electricity cables and telephone cables are buried in the ground, these facilities are liable to be damaged by the digging bucket of the excavator during the construction work. And when these accidents are brought about, the dwellers in the neighbourhood are caused several troubles such as failures of water supply and power supply, and inundation, in addition to that they incur the damage of their lives by the accident such as explosion of the city-gas.
  • the object of the invention is to prevent such accidents and troubles from occurring. Further object of the invention is to provide a novel excavator which can proceed the digging work without causing such accidents and troubles, i.e. the damages of water pipes, gas pipes, electricity cables and telephone cables.
  • the present invention proposes an improved excavator which is provided with a transmitter, a receiver and antennae of a buried metal detector, in which said antennae comprise three antennae attached to the bucket arm portion of the excavator, and is disposed in three dimensional perpendicular relation with each other. Further, the receiver as provided can be interlocked to the driving source of the bucket arm, thereby when the signal form a buried metal article is detected, the work of the bucket is immediately stopped to prevent the damage of said article.
  • FIG. 1 is a schematic illustration of the use of the excavator
  • FIG. 2 is a plan view of the bucket in which the antennae are diposed according to the invention.
  • FIGS. 3, 4 and 5 are diagrams showing the characteristics of the buried metal detector and FIG. 6 shows the interlocking of the power source of the excavator of FIG. 1 with a receiver in accordance with one aspect of this invention.
  • the numeral 1 indicates a back hoe
  • the numeral 2 is a digging arm of the back hoe 1
  • the numerals 3, 4 and 5 are bar antennae.
  • the bar antennae 3, 4 and 5 are disposed adjacently to the bucket 6 of the digging arm 2 in three dimensional arrangement imaliifih'r, i.e., in the perpendicular relations.
  • the numeral 7 is a transmitter of a buried metal detector and the numeral 8 is a receiver, both of which are installed within the back hoe 1.
  • the numeral 9 indicates a buried metal pipe.
  • the transmitter 7 and the receiver 8 of the buried metal detector which are employed in the device of the present invention have respective loop coils.
  • the directivity of the electromagnetic wave shows the figure 8 characteristic as shown in FIG. 3. Accordingly, the intensity of the electromagnetic wave is most strong in the direction of A A, and in other directions, for example, in the directions of B and C, the intensity decreases gradually, and at last the intensity of the electromagnetic wave becomes the minimum.
  • the electromagnetic wave when the transmitter 7 is put up on the ground, the electromagnetic wave is radiated into the ground, and if a metallic article such as a metal pipe or cable is buried in the ground, the electromagnetic'field is induced by said metallic article as shown in FIG. 4.
  • the intensity of this electromagnetic wave becomes larger, if the metallic article is buried in a shallow place, or the metallic article is large or the direction of the metallic article is parallel to the face of the coil. While, if the direction of the metallic article is inclined to the face of the coil in like manner as the arrow B or C in FIG. 3, the intensity of the electromagnetic wave is reduced as much.
  • a receiver is placed in the electromagnetic field thus induced, several receiver sensitivities will be obtained according to the position of the receiver. As indicated in FIG.
  • the receiver sensitivity is largest in the position E, it is decreased in some degree in the position F, and it is the minimum in the position G. And the farther the receiver is moved away, the smaller the receiver sensitivity becomes, as indicated by the mark H.
  • the buried metal detector has the above-mentioned characteristic, thus the transmitter is placed previously just above the buried metal pipe in adjacent to the construction site, in which the loop coil of the transmitter is disposed in paralles with the buried metal 9, thereby the electromagnetic field is produced on the buried metallic pipe 9. Accordingly, if the aforementioned back hoe 1 get near the buried pipe 9, the pipe 9 in any direction can be detected by the set of three antennae 3, 4 and 5 which are attached on the digging arm 2 of the back hoe l in three perpendicular directions. In the meantime, by interlocking the receiver 8 with the power source 11 of the back hoe 1, via lead 12 (see FIG. 6) the latter can be totally stopped just upon the detection of the buried metallic pipe 9 by said antennae. Further, the distance between the buried pipe 9 and the top portion of the bucket 6 of the back hoe I in which the back hoe l is to be stopped, can be regulated by adjusting the sensitivity of the receiver 3.
  • the device of the present invention is very effective and advantageous in the construction site.
  • the conventional electromagnetic relay can be used according to well known manner.
  • An excavator having a bucket arm and which is when a signal is received by said receiver.

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  • Engineering & Computer Science (AREA)
  • Mining & Mineral Resources (AREA)
  • Civil Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Structural Engineering (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Mechanical Engineering (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Paleontology (AREA)
  • Environmental & Geological Engineering (AREA)
  • Geology (AREA)
  • Remote Sensing (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Geophysics (AREA)
  • Component Parts Of Construction Machinery (AREA)
  • Geophysics And Detection Of Objects (AREA)
  • Investigation Of Foundation Soil And Reinforcement Of Foundation Soil By Compacting Or Drainage (AREA)

Abstract

An improved excavator which is provided with a transmitter, a receiver and antennae of a buried metal detector, being characterized in that said antennae comprise three antennae which are disposed in the bucket arm of said excavator in three dimensional perpendicular relation, and thereby the damages of buried metal facilities can be prevented.

Description

United States Patent [191 Appl. No.: 309,888
Foreign Application Priority Data Field of Search 214/761, 762, 764; 324/41 324/67; 37/DlG. 19; 56/102, D16. 15
References Cited UNITED STATES PATENTS Maust 37/D1G. l9
[111 3,858,737 Senoo 3 1 1 Jan. 7, 1975 [5 EXCAVATOR 2,409,397 l0/l946 Sheehan r. 37/DlG, 19 [76] Inventor: Rikizo Senoo, 2-14, Nihombashi figgfigfff Kakigara-cho, Chuo-ku, Tokyo,
Japan Primary ExamtnerRobert J. Spar i 1 Fllfidi 1972 Assistant Examiner-John Mannix Attorney, Agent, or FirmLerner, David, Littenberg & Samuel [57] ABSTRACT An improved excavator which is provided with a transmitter, a receiver and antennae of a buried metal detector, being characterized in that said antennae comprise three antennae which are disposed in the bucket arm of said excavator in three dimensional perpendicular relation. and thereby the damages of buried metal facilities can be prevented.
3 Claims, 6 Drawing Figures PATENTED JAN 7 5 SHEEF 2 OF 2 mumSsw mwk 0Q EXCAVATOR FIELD OF THE INVENTION The present invention relates to an improved excavator for digging the soil. Further, the invention relates to the excavator which is provided with a transmitter, a receiver and antennae of a buried metal detector being characterized in that said antennae comprise three antennae and positioned in the bucket arm of the excavator in three dimensional perpendicular relation. Still further, the invention relates to the excavator which can detect the buried metal facilities to stop the bucket arm thereof.
BACKGROUND OF THE INVENTION Excavators are generally employed for digging the soil in construction site, and if the public facilities such as city-water pipes, gas pipes, electricity cables and telephone cables are buried in the ground, these facilities are liable to be damaged by the digging bucket of the excavator during the construction work. And when these accidents are brought about, the dwellers in the neighbourhood are caused several troubles such as failures of water supply and power supply, and inundation, in addition to that they incur the damage of their lives by the accident such as explosion of the city-gas.
Therefore, the object of the invention is to prevent such accidents and troubles from occurring. Further object of the invention is to provide a novel excavator which can proceed the digging work without causing such accidents and troubles, i.e. the damages of water pipes, gas pipes, electricity cables and telephone cables.
BRIEF SUMMARY OF THE INVENTION Pursuant to the above objects, the present invention proposes an improved excavator which is provided with a transmitter, a receiver and antennae of a buried metal detector, in which said antennae comprise three antennae attached to the bucket arm portion of the excavator, and is disposed in three dimensional perpendicular relation with each other. Further, the receiver as provided can be interlocked to the driving source of the bucket arm, thereby when the signal form a buried metal article is detected, the work of the bucket is immediately stopped to prevent the damage of said article.
BRIEF DESCRIPTION OF THE DRAWINGS These and other feature of the invention will be more fully understood by referring to the following detailed description presented solely for the purpose of illustration and to the accompanying drawings in which:
FIG. 1 is a schematic illustration of the use of the excavator;
FIG. 2 is a plan view of the bucket in which the antennae are diposed according to the invention;
FIGS. 3, 4 and 5 are diagrams showing the characteristics of the buried metal detector and FIG. 6 shows the interlocking of the power source of the excavator of FIG. 1 with a receiver in accordance with one aspect of this invention.
DETAILED DESCRIPTION OF THE INVENTION Now referring to the drawings, the excavator of the present invention will be explained. In the drawings,
the numeral 1 indicates a back hoe, the numeral 2 is a digging arm of the back hoe 1, and the numerals 3, 4 and 5 are bar antennae. As shown in FIG. 2, the bar antennae 3, 4 and 5 are disposed adjacently to the bucket 6 of the digging arm 2 in three dimensional arrangement imaliifih'r, i.e., in the perpendicular relations. The numeral 7 is a transmitter of a buried metal detector and the numeral 8 is a receiver, both of which are installed within the back hoe 1. Further, the numeral 9 indicates a buried metal pipe.
The transmitter 7 and the receiver 8 of the buried metal detector which are employed in the device of the present invention, have respective loop coils. In general, when these loop coils are positioned on the ground perpendicularly, the directivity of the electromagnetic wave shows the figure 8 characteristic as shown in FIG. 3. Accordingly, the intensity of the electromagnetic wave is most strong in the direction of A A, and in other directions, for example, in the directions of B and C, the intensity decreases gradually, and at last the intensity of the electromagnetic wave becomes the minimum.
Thus, when the transmitter 7 is put up on the ground, the electromagnetic wave is radiated into the ground, and if a metallic article such as a metal pipe or cable is buried in the ground, the electromagnetic'field is induced by said metallic article as shown in FIG. 4. The intensity of this electromagnetic wave becomes larger, if the metallic article is buried in a shallow place, or the metallic article is large or the direction of the metallic article is parallel to the face of the coil. While, if the direction of the metallic article is inclined to the face of the coil in like manner as the arrow B or C in FIG. 3, the intensity of the electromagnetic wave is reduced as much. In case a receiver is placed in the electromagnetic field thus induced, several receiver sensitivities will be obtained according to the position of the receiver. As indicated in FIG. 5, if the receiver 8 is positioned in the magnetic field of the electromagnetic wave 10 which is induced by the transmitter 7, the receiver sensitivity is largest in the position E, it is decreased in some degree in the position F, and it is the minimum in the position G. And the farther the receiver is moved away, the smaller the receiver sensitivity becomes, as indicated by the mark H.
The buried metal detector has the above-mentioned characteristic, thus the transmitter is placed previously just above the buried metal pipe in adjacent to the construction site, in which the loop coil of the transmitter is disposed in paralles with the buried metal 9, thereby the electromagnetic field is produced on the buried metallic pipe 9. Accordingly, if the aforementioned back hoe 1 get near the buried pipe 9, the pipe 9 in any direction can be detected by the set of three antennae 3, 4 and 5 which are attached on the digging arm 2 of the back hoe l in three perpendicular directions. In the meantime, by interlocking the receiver 8 with the power source 11 of the back hoe 1, via lead 12 (see FIG. 6) the latter can be totally stopped just upon the detection of the buried metallic pipe 9 by said antennae. Further, the distance between the buried pipe 9 and the top portion of the bucket 6 of the back hoe I in which the back hoe l is to be stopped, can be regulated by adjusting the sensitivity of the receiver 3.
Thus if the device of the present invention is used in the excavation work, the buried pipe 9 is never caused damage because the back hoe 1 can be stopped immediately on the detection of the pipe 9 by the antennae 3, 4 and 5. Therefore, the device of the present invention is very effective and advantageous in the construction site.
Further, in order to turn back the stopped bucket 6 of the back hoe l, the conventional electromagnetic relay can be used according to well known manner.
It should be emphasized, however, that the specific embodiments described and shown herein are intended as merely illustrative and in no way restrictive of the invention.
What is claimed is:
1. An excavator having a bucket arm and which is when a signal is received by said receiver.

Claims (3)

1. Ajn excavator having a bucket arm and which is provided with a buried metal detector including a transmitter, a receiver and an antennae, in which said antennae comprises three elements; said three elements being positioned on said bucket arm of said excavator and are disposed in three-dimensional mutually perpendicular relationship with each other.
2. An excavator as defined in claim 1 in which said three elements are bar antennae.
3. An excavator as defined in claim 1 also including: means for interlocking said receiver to the driving source of said bucket arm to stop said bucket arm when a signal is received by said receiver.
US309888A 1971-12-02 1972-11-27 Excavator Expired - Lifetime US3858737A (en)

Applications Claiming Priority (1)

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JP1971113355U JPS5148805Y2 (en) 1971-12-02 1971-12-02

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DE (1) DE2257951B2 (en)
FR (1) FR2162172B1 (en)
GB (1) GB1404617A (en)

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2626532A1 (en) * 1975-06-14 1976-12-30 Electrolocation Ltd DEVICE AND METHOD FOR DETERMINING UNDERGROUND CABLES, PIPELINES AND THE LIKE
US4070625A (en) * 1976-09-14 1978-01-24 Dravo Corporation Apparatus for measuring the distance to the floor of the cargo hold of a ship through intervening bulk material
US4600356A (en) * 1984-01-27 1986-07-15 Gas Research Institute Underground pipeline and cable detector and process
EP0490855A1 (en) * 1990-12-14 1992-06-17 Servoindikator Hb Pointer
US5371959A (en) * 1990-12-14 1994-12-13 Servoindikator Hb Pointing device carried by digging arm of excavator, for dynamically indicating location and direction of extension of underground cable
US5479729A (en) * 1994-04-04 1996-01-02 At&T Corp. Method and apparatus for controlling excavation eqiupment
US5592092A (en) * 1994-10-28 1997-01-07 Gas Research Institute Pipe proximity warning device for accidental damage prevention mounted on the bucket of a backhoe
US20100321021A1 (en) * 2009-06-23 2010-12-23 Jack Alexander Siegel Metal detection excavation apparatus and method
WO2016090412A1 (en) * 2014-12-09 2016-06-16 Cmte Development Limited Method and system for the detection of conductive objects
CN111565555A (en) * 2017-11-06 2020-08-21 Brp集团私人有限责任公司 Electromagnetic frequency (EMF) detection safety shovel for detecting the presence of underground power cables during excavation

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4027020C2 (en) * 1990-08-27 1994-08-25 Heinrich Liebig Gmbh Method and device for determining the presence of metallic reinforcement elements in the interior of a concrete component
DE4233441A1 (en) * 1992-07-21 1994-01-27 Zikun Fahrzeugbau Gmbh Auxiliary device for vehicle with articulated parts or tools for working on electric power lines - has sensor for detecting metal objects or electromagnetic and/or electrostatic fields and evaluation unit connected to alarm and/or actuator
GB2337120B (en) * 1998-05-07 2003-04-09 Radiodetection Ltd Detecting underground conductors
DE102008059365A1 (en) * 2008-11-28 2010-06-02 Symeo Gmbh Position and/or alignment-determining device for fork lift, has evaluation device to determine position and/or alignment of component of device, and antennas aligned relative to each other in different spatial directions of surrounding area

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2131291A (en) * 1936-06-16 1938-09-27 Charles I Maust Signal system for excavators
US2409397A (en) * 1943-10-13 1946-10-15 Edward F Sheehan Safety cutoff for power-operated hand tools
US3418572A (en) * 1966-02-11 1968-12-24 Thomas G. Humphreys Jr. Apparatus including variable frequency indicating means for locating and tracing conductive structures
US3617865A (en) * 1968-05-25 1971-11-02 Goroku Hakata Method and apparatus for locating a buried metallic line employing magnetic field gradient measurements

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2131291A (en) * 1936-06-16 1938-09-27 Charles I Maust Signal system for excavators
US2409397A (en) * 1943-10-13 1946-10-15 Edward F Sheehan Safety cutoff for power-operated hand tools
US3418572A (en) * 1966-02-11 1968-12-24 Thomas G. Humphreys Jr. Apparatus including variable frequency indicating means for locating and tracing conductive structures
US3617865A (en) * 1968-05-25 1971-11-02 Goroku Hakata Method and apparatus for locating a buried metallic line employing magnetic field gradient measurements

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2626532A1 (en) * 1975-06-14 1976-12-30 Electrolocation Ltd DEVICE AND METHOD FOR DETERMINING UNDERGROUND CABLES, PIPELINES AND THE LIKE
US4070625A (en) * 1976-09-14 1978-01-24 Dravo Corporation Apparatus for measuring the distance to the floor of the cargo hold of a ship through intervening bulk material
US4600356A (en) * 1984-01-27 1986-07-15 Gas Research Institute Underground pipeline and cable detector and process
EP0490855A1 (en) * 1990-12-14 1992-06-17 Servoindikator Hb Pointer
WO1992010619A1 (en) * 1990-12-14 1992-06-25 Servoindikator Hb Pointer
US5371959A (en) * 1990-12-14 1994-12-13 Servoindikator Hb Pointing device carried by digging arm of excavator, for dynamically indicating location and direction of extension of underground cable
US5479729A (en) * 1994-04-04 1996-01-02 At&T Corp. Method and apparatus for controlling excavation eqiupment
US5592092A (en) * 1994-10-28 1997-01-07 Gas Research Institute Pipe proximity warning device for accidental damage prevention mounted on the bucket of a backhoe
US20100321021A1 (en) * 2009-06-23 2010-12-23 Jack Alexander Siegel Metal detection excavation apparatus and method
WO2016090412A1 (en) * 2014-12-09 2016-06-16 Cmte Development Limited Method and system for the detection of conductive objects
CN111565555A (en) * 2017-11-06 2020-08-21 Brp集团私人有限责任公司 Electromagnetic frequency (EMF) detection safety shovel for detecting the presence of underground power cables during excavation

Also Published As

Publication number Publication date
FR2162172B1 (en) 1975-01-03
FR2162172A1 (en) 1973-07-13
DE2257951B2 (en) 1976-02-05
DE2257951A1 (en) 1973-06-07
JPS5148805Y2 (en) 1976-11-25
GB1404617A (en) 1975-09-03
JPS4869202U (en) 1973-09-01

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