JPS552139A - Detection of opening and closing of manhole cover - Google Patents

Detection of opening and closing of manhole cover

Info

Publication number
JPS552139A
JPS552139A JP7474478A JP7474478A JPS552139A JP S552139 A JPS552139 A JP S552139A JP 7474478 A JP7474478 A JP 7474478A JP 7474478 A JP7474478 A JP 7474478A JP S552139 A JPS552139 A JP S552139A
Authority
JP
Japan
Prior art keywords
opening
closing
inductance
manhole cover
coiled
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP7474478A
Other languages
Japanese (ja)
Inventor
Akira Watanabe
Hisashi Hamanaka
Masao Abe
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Taiko Electric Works Ltd
Original Assignee
Taiko Electric Works Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Taiko Electric Works Ltd filed Critical Taiko Electric Works Ltd
Priority to JP7474478A priority Critical patent/JPS552139A/en
Publication of JPS552139A publication Critical patent/JPS552139A/en
Pending legal-status Critical Current

Links

Landscapes

  • Underground Structures, Protecting, Testing And Restoring Foundations (AREA)

Abstract

PURPOSE: To detect opening and closing of the manhole cover with a simple structure which performs a positive operation by associating a coiled inductance with the manhole cover so that the value of the inductance will vary in response to the opening and closing of the lid.
CONSTITUTION: At least one coiled inductance 1 is provided with the manhole the opening and closing of whose lid is to be detected. When a magnetic element 2 which varies the value of the coiled inductance 1 is moved in the direction P by the opening of the manhole cover, the inductance 1 outputs signal, which is detected by a detector 3 and sent to an alarming apparatus 6 through a connector 5. The alarming apparatus 6 alarms visually or audibly by lighting a lamp or sounding a buzzar. This detector, simply constituted, can withstand hard conditions and per form practical detection.
COPYRIGHT: (C)1980,JPO&Japio
JP7474478A 1978-06-20 1978-06-20 Detection of opening and closing of manhole cover Pending JPS552139A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP7474478A JPS552139A (en) 1978-06-20 1978-06-20 Detection of opening and closing of manhole cover

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP7474478A JPS552139A (en) 1978-06-20 1978-06-20 Detection of opening and closing of manhole cover

Publications (1)

Publication Number Publication Date
JPS552139A true JPS552139A (en) 1980-01-09

Family

ID=13556053

Family Applications (1)

Application Number Title Priority Date Filing Date
JP7474478A Pending JPS552139A (en) 1978-06-20 1978-06-20 Detection of opening and closing of manhole cover

Country Status (1)

Country Link
JP (1) JPS552139A (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2009150217A (en) * 2002-08-12 2009-07-09 David M Stadler Device and method for locking cover of catch basin and manhole, and the like
NL2002518C2 (en) * 2009-02-11 2010-08-12 Oldewening DEVICE FOR SECURING A FLOOR OPENING.
CN101994321A (en) * 2009-08-31 2011-03-30 南通芯迎设计服务有限公司 Luminous sewer cover
JP2024055055A (en) * 2022-10-06 2024-04-18 鹿島建設株式会社 Warning Device

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2009150217A (en) * 2002-08-12 2009-07-09 David M Stadler Device and method for locking cover of catch basin and manhole, and the like
NL2002518C2 (en) * 2009-02-11 2010-08-12 Oldewening DEVICE FOR SECURING A FLOOR OPENING.
CN101994321A (en) * 2009-08-31 2011-03-30 南通芯迎设计服务有限公司 Luminous sewer cover
JP2024055055A (en) * 2022-10-06 2024-04-18 鹿島建設株式会社 Warning Device

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