Disclosure to Promote the Right To Information

Whereas the Parliament of India has set out to provide a practical regime of right to information for citizens to secure access to information under the control of public authorities, in order to promote transparency and accountability in the working of every public authority, and whereas the attached publication of the Bureau of Indian Standards is of particular interest to the public, particularly disadvantaged communities and those engaged in the pursuit of education and knowledge, the attached public safety standard is made available to promote the timely dissemination of this information in an accurate manner to the public.

इंटरनेट मानक

“!ान $ एक न' भारत का +नम-ण”Satyanarayan Gangaram Pitroda

“Invent a New India Using Knowledge”

“प0रा1 को छोड न' 5 तरफ”Jawaharlal Nehru

“Step Out From the Old to the New”

“जान1 का अ+धकार, जी1 का अ+धकार”Mazdoor Kisan Shakti Sangathan

“The Right to Information, The Right to Live”

“!ान एक ऐसा खजाना > जो कभी च0राया नहB जा सकता है”Bhartṛhari—Nītiśatakam

“Knowledge is such a treasure which cannot be stolen”

“Invent a New India Using Knowledge”

है”ह”ह

IS 7544 (1975): Parallel Ruler (roller type) [PGD 22:Educational Instruments and Equipment]

IS : 7544 - 1975

Indian Standard SPECIFICATION FOR

PARALLEL RULER (ROLLER TYPE)

Optical and Mathematical Instruments Sectional Committee, EDC 36 Chairman Representing

DR C. S. RAO Kailas, Frenchpet, Machilipatnam

Members

SHRI A. ALVAR~ZS All India Instrument Manufacturers and Dealers’ Association, Bombay

SHRI V. K. VASUDEVAN ( Alternate ) &RI MADHO RAM BHARDWAJ Quality Marked Goods Manufacturers’ Co-operative

Association Ltd, Roorkee SHRI SOME PRAKA~H SHARMA ( Alternate )

Ministry of Defence ( R & D ) Survey of India, Dehra Dun

SHRI A. N. BHATTACHARYA SHRI J. CHATTERJEE

SHRI R. S. CHUOH ( Alternate ) CHIEF HYDRD~;;~~;R ( NAVY ) DEPUTY , STANDARDS

( TRACK ) ASSISTANT DIRECTOR, STAND-

ARD ( TRACK ) ( Alfernate) DIRECTOR, INSTRUMENTS RESEARCH

& DEVELOPMENT ESTABLISHMENT SHRI K. P. SINGH ( Alternate )

SHRI P. F. GHADIALLI

Naval Headquarters Research, Designs & Standards Organization

(Mmistry of Railways), Lucknow

Ministry of Defence ( R & D ), Dehra Dun

The Byi;Eynical Engineers Association ( India ),

Ministry of Defence ( DGOF ) National Physical Laboratory ( CSIR ), New Delhi

SHRI M. M. GUPTA SHRI P. C. JAIN

SHRI RAM PRA~AD ( Alternate ) SHRI P. K. JAIN

SHRI D. D. KHOSLA ( Alternate ) COL K. L. KHOSLA COL N. P. MANAKTALA

LT-COL H. LAL ( Alternate ) SHRI B. R. MANKHAND SHRI L. M. MATHUR

Directorate of Industries, Government of Haryana, Chandigarh

The Institution of Surveyors, New Delhi Ministry of Defence ( DGI )

The Koh-I-Noor ( India ) Private Limited, Varanasi Development Commissioner, Small Scale Industries,

New Delhi DR M. V. R. K._MURTY Bhabha Atomic Research Centre, Bombay .\

DR K. V. S. R. APPA RAO ( Alternaze 1 DR J. PRASAD Central Scientific Instruments

( CSIR ), Chandigarh SHRI RAM SINGH ( Alternate )

Organization

@ Copvright 1975

(Continued on page 2 )

INDIAN STANDARDS INSTITUTION

This publication is protected under the Indian Copyright Act ( XIV of 1957 ) and reproduction in whole or In part by any f”eans except with written permission of the publisher shall be deemed to be an infrmgement of copyright under the said Act.

IS : 7544 - 1975

( Continuedfrom page 1 )

Members Rc@snting

SHRI E. B. RAJDERKAR Raj-Der-Kar & Co, Bombay KUMARI SUBAS RAJDERKAR ( Altcrmte )

LT-COL RAMAOHANDER Army Headquarters, Delhi SHRI K. N. RAMASWAMY Directorate General of Technical Develooment.

SHRI P. V. MAMMEN ( Alternate) SHRICNARAYANARAO DRI.RAYAKRWINA RAO

COL G. S. SIHOTA

SHRl T. R. SWHNEY SHRI K . G. TORGAL

Sum A. K. GHOSAL ( Alternate) SHRI H. C. VERMA

SHRI K. G. P~RANG ( Alternate) SHRI S. M. RAZVI,

Director ( Mech Engg )

New Delhi

The Andhra Scientific Co Ltd, Machilipatnam In personal capacity ( Toshniwal Znstruments &

Engineering Co, .New Delhi ) Directorate General of Armed Forces Medical

Service, Ministry of Defence Indian Engineering Association, Calcutta The National Instruments Ltd, Calcutta

Associated Instrument Manufacturers ( India ) Pvt Ltd, New Delhi

Director General, IS1 ( Ex-o&i0 Member )

Secretary

SHRI S. P. ABBEY

Arsistant Director ( Mech Engg ), IS1

Drawing Instruments Subcommittee, EDC 36 : 1

Convener

COL K. L. KHOSLA The Institution of Surveyor, New Delhi

Members

SHRI B. P. AQRAWAL

SHRI S. M. NICAM ( Alternate ) SHRIJ. CHATTERJEE SHRI S. K. GAUTAM

Quality Marking Scheme, Directorate of Industries, Kanpur ( U.P. )

SHRIP.L.BHARDWAJ (Alternate SHRI S. K. GUPTA

SHRI G. D. BAKSHI ( Alternate) SHRI P. C. JAIN Sum B. R.MANKHAND CAPTS.PAUL

Survey of India, Dehra Dun Quality Marked Goods Manufacturer’s Co-operative

Association Ltd, Roorkee ) Ministry of Defence ( DGI )

SmuD.D.PURX

National Physical Laboratory ( CSIR ), New Delhi The Koh-I-Noor ( India ) Private Limited, Varanasi Director of Electrical 8s Mechanical Engineering,

Army Headquarters, New Delhi Central Scientific Instruments Organization ( CSIR),

Chandigarh SHRI K. N. RAMASWAMY Direc;tot;el~ieneral of Technical Development,

SHRI P. V. MA-N ( Alternate ) SHRI K. RAMA RAO Ministry of Defence ( R St D ) SHRI s. c. Sr3AH

SHRI S. R. PIYY~E ( Alternute ) Raja Bahadur Motilal Poona Mills Ltd, Poona

2

IS : 7544 - 1975

Indian Standard SPECIFICATION FOR

PARALLEL RULER { ROLLER TYPE)

0. FOREWORD ,

0.1 This Indian Standard was adopted by the Indian Standards Institution on 27 January 1975, after the draft finalized by the Optical and Mathematical Instruments Sectional Committee had been approved by the Mechanical Engineering Division Council.

0.2 For the purpose of deciding whether a particular requirement of this standard is complied with, the final value, observed or calculated, express- ing the result of test, shall be rounded off in accordance with IS : 2-1960*. The number of significant places retained in the rounded off value should be the same as that of the specified value in this standard.

1. SCOPE

1.1 This standard covers the requirements for parallel ruler which is used for drawing parallel lines.

2. DESCRIPTION

2.1 The ruler consists of a metallic base whose upper long edges are bevelled and is fitted with widely spaced rollers united by an axle. The axle runs in bearings and is protected by a bridge mounted between the rollers. The nomenclature of the various parts of the ruler is shown in Fig. 1.

3. DIMENSIONS

3.1 The sizes of the ruler and the dimensions of the base, rollers and bridge shall be as given in Table 1 read with Fig. 1.

4. MATERIAL AND GENERAL REQUIREMENTS

4.1 The base shall be made of hard rolled brass, stainless steel or rust- proof steel. It shall be flat, straight and edges parallel within the tolerances specified in 5.2.

4.2 The ruling edges shall be bevelled on the top face for a width of 10 mm and to a-thickness 1.5 mm approximately.

*Rules for rounding off numerical values ( rrcrwSd ) .

3

SECTIGN XX

FIG. 1 NOMENCLATURE AND DIMENSIONS FOR PARALLEL RULER

IS : 7544 - 1975

TABLE 1 SIZES AND DIMENSIONS FOR PARALLEL RULERS

I SIZE OF RULER

300

450

600

750

( Clause 3.1, and Fig. 1 )

All dimensions in millimetres.

BASE ROLLERS LENQTH

BR%E 1 b

ML Diameter Width

Min hl +=l

~~

300 65 4.5 25 25 150 ---

450 65 4.5 25 25 250

600 65 4.5 25 25 400

-~

750 65 4.5 25 25 550

4.3 The rollers shall be of hard drawn brass rod, stainless steel or rust- proof steel and shall be truly mounted on the axle. The diameter of each pair of rollers shall be the same.

4.4 The rollers shall have longitudinal parallel serrations to avoid slipping on the drawing paper.

4.5 The bearings~and bridge shall be secured to the base by screws. The screws shall either be flush with the surface of the base or shall be embedded. The bridge may be made of brass whereas the axle shall be of stainless steel, plated mild steel or phosphor bronze.

4.6 Two knobs of any suitable material shall be provided on the base near the two edges for ease of handling.

4.7 All parts of the ruler shall be suitably finished.

4.8 The ruler shall be provided with a suitable case made of well seasoned wood or any other suitable material.

5. FUNCTIONAL REQUIREMENTS

5.1 The axle ends shall run freely in the bearings without shake or undue end play.

5

IS : 7544 - 1975

5.2 The -edges of the ruler shall not deviate from straightness by more than 0.05 mm and their plane surfaces shall not vary from a plane by more than O-1 mm at any point.

6. TESTS

6.1 The ruler shall be tested by drawing three parallel lines 500 mm apart by using one edge only. The ruler shall then be reversed and set parallel to one of the lines and when traversed over other lines, the edge of the ruler shall be parallel to the line. When traversed to the next line, the edge of ruler shall be parallel to the line drawn within ho.25 mm.

6.2 There shall not be any appreciable play between the rollers and the bearings.

7. MARKING

7.1 The maker’s name or trade-mark and year of manufacture shall be legibly and indelibly marked at a suitable place on the ruler.

7.1.1 The rulers may also be marked with the IS1 Certification Mark.

NOTE- The use of the ISI Certification Mark is governed by the provisions of the Indian Standards Institution ( Certification Marks ) Act and the Rules and Regulations made thereunder. The IS1 Mark on products covered by an Indian Standard conveys the assurance that they have been produced to comply with the requirements of that standard under a well-defined system of inspection, testing and quality control which is devised and supervised by IS1 and operated by the producer. IS1 marked products are also continuously checked by IS1 for conformity to that standard as a further safeguard. Details of conditions under which a licence for the use of the IS1 Certification Mark may be granted to manufacturers or processors, may be obtained from the Indian Standards Institution.

8. PACKING AND PACKAGING

8.1 The ruler shall be wrapped in a tissue paper and shall be then placed in its case.

6