-vinngi Hureau o1 5tandards NBS

taken from the library.

TECHNICAL NOTE

295

DISCLOSURES ON:

A Transrotor Engine,

High Temperature Platinum Resistance Thermometer,

Dynamic Analog Correlation System, and

Combination Metering and Safety Valve for Filling

Sonde Ballons With Hydrogen

(I

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U.S. DEPARTMENT OF COMMERCE

National Bureau of Standards
THE NATIONAL BUREAU OF STANDARDS

The National Bureau of Standards^ provides measurement and technical information ser\ices

essential to the efficiency and effectiveness of the work of the Nation's scientists and engineers. The

Bureau serves also as a focal point in the Federal Government for assuring maximum application of the physical and engineering sciences to the advancement of technology in industry and commerce. To

accomplish this mission, the Bureau is organized into three institutes covering broad program areas of research and services: THE INSTITUTE FOR BASIC STANDARDS . . . provides the central basis within the United

States for a complete and consistent system of physical measurements, coordinates that system with the measurement systems of other nations, and furnishes essential services leading to accurate and uniform

physical measurements throughout the Nation's scientific community, industry, and commerce. This

Institute comprises a series of divisions, each serving a classical subject matter area: —Applied Mathematics—Electricity—Metrology—Mechanics—Heat—Atomic Physics—Physical

Chemistry—Radiation Physics—Laboratory Astrophysics'—Radio Standards Laboratory,- which

includes Radio Standards Physics and Radio Standards Engineering—Office of Standard Refer- ence Data. THE INSTITUTE FOR MATERIALS RESEARCH . . . conducts materials research and provides

associated materials services including mainly reference materials and data on the properties of materials. Beyond its direct interest to the Nation's scientists and engineers, this Institute yields services which are essential to the advancement of technology in industry and commerce. This Institute is or- ganized primarily by technical fields: —Analytical Chemistry—Metallurgy—Reactor Radiations—Polymers—Inorganic Materials—Cryogenics-—Materials Evaluation Laboratory—Office of Standard Reference Materials. THE INSTITUTE FOR APPLIED TECHNOLOGY . . . provides technical services to promote the use of available technology and to facilitate technological innovation in industry and government. The

principal elements of this Institute are: —Building Research—Electronic Instrumentation—Textile and Apparel Technology Center

Technical Analysis—Center for Computer Sciences and Technology—Office of Weights and Measures—Office of Engineering Standards Services—Office of Invention and Innovation—Clearinghouse for Federal Scientific and Technical Information.*

1 Headquarters and Laboratories at Gaithersburg, Maryland, unless otherwise noted; mailing address Washington, D. C.

20234.

2 Located at Boulder, Colorado, 80302.

3 Located at 5285 Port Royal Road, Springfield, Virginia, 2215L
UNITED STATES DEPARTMENT OF COMMERCE • John T. Connor, Secretary

NATIONAL BUREAU OF STANDARDS • A. V. Astin, Director

<^^TECHNICAL NOTE 295

ISSUED OCTOBER 21, 1966

DISCLOSURES ON:

A Transrotor Engine,

High Temperature Platinum Resistance Thermometer,

Dynamic Analog Correlation System, and

Combination Metering and Safety Valve for Filling

Sonde Ballons With Hydrogen

Editors: David Robbins and Alvin J. Englert

NBS Technical Notes are designed to supplement the Bureau's regular publications program. They provide a means for making available scientific data that are of transient or limited interest. Technical Notes may be

listed or referred to in the open literature.

For sale by the Superintendent of Documents, Government Printing Office

Washington, D.C., 20402 - Price 25 cents

TABLE OF CONTENTS

Title

A Transrotor Engine

Author Page

Seymour Henig 1 National Bureau of Standards

Vvashington, D. C. 20234

High Temperature Platinum

Resistance Thermometer

Leslie A. Guildner

Richard L. Anderson

National Bureau of Standards

Washington. D. C. 20234

Dynamic Analog Correlation

System

Robert W. Hubbard

Environmental Science

Services Administration

Boulder, Colorado 80301

Combination Metering and William AA/. Richardson

Safety Valve for Filling Weather Bureau

Sonde Balloons with Hydrogen Environmental Science

Services Administration

Washington, D. C. 20910

16

111
This booklet presents descriptions and drawings of four devices,

embodying interesting and unusual solutions to problems frequently encountered in their respective fields: a transrotor engine, a dynamic

analog correlation system, a high temperature platinum resistance thermometer, and a combination metering and safety valve for filling sonde

balloons with hydrogen.

Other disclosures on various subjects may be found in NBS

Technical Notes 237, 253, 263, 282 and 287.

All property rights in the devices, methods, and systems described in the above disclosures, unless otherwise noted, have been

retained by the United States Government as represented by the Secretary of Commerce.

Tech. Note No. 295, October 14, 1966

iv
A TRANSROTOR ENGINE

Seymour Henig

VIEW /^

SECTION C-C

Tiq~. 4-

SECTION B-B

Fij.:l

SECTION D-D

Fig:.

Tech. Note No. 295, October 14, 1966

1
A TRANSROTOR ENGINE

Seymour Henig

COMPRESSION

CHAMBBR

COM.

PRESS ION

MIN. CHf^MBEfi -Mlhi

INTAKE

EXHAUST

EXP/^MStON

MAX

CH/iMBtR

Fij.5 Fij6

Tech. Note No. 295, October 14, 1966

2
A TRANSROTOR ENGINE

Seymour Henig *

This note describes an engine of inherent rotational balance which

retains the operating characteristics of a four-stroke cycle internal

combustion reciprocating engine. Sine the kinematics of the engine's

mechanism feature simple rotation, with the absence of reciprocation,

it may be considered to operate on a four-phase cycle.

The engine employs two sets of gerotor components 10, II (Fig. 5)

and 12, 13 (Fig. 6) that are positioned in circular cavities 14 and 15,

respectively, in engine block 16 (Fig. 1). The inner gerotor components 10 and 12 are keyed to a common shaft 17, but to simplify the

drawings the two sets of gerotor components are shown separate from

their cavities. Each set is shown in two positions of rotation to show

the phase-limit chamber size relationship.

Each inner rotor component 10 and 12 rotates on an axis coincident with the axis of rotation of output shaft 17. The axis of rotation

of the outer gerotor components 11 and 13 are designated as 20 and 21,

respectively, (Fig. 4) and are located on the center axis of their

related cavities. Relative to the center of the output shaft, the axes

of the outer gerotor components are displaced 90° from each other.

This 90° angular displacement is illustrative and not a requirement.

*All rights in the engine described in this Note have been retained by

Seymour Henig, subject to a nonexclusive, irrevocable, royalty-free

license to the Government with power to grant licenses for all governmental purposes.

Tech. Note No, 295, October 14, 1966

3
spark plug 30 is mounted so that its electrodes have access to

transfer passageway 26. Seal bearings 24 are shown symbolically.

A combustible mixture is fed to inlet port 2 5 (Fig. 2) by a conventional arrangement such as a carburetor, not shown. Rotation of shaft

17 causes the fuel-air mixture to be drawn through the port into an

enlarging chamber formed by opposing tooth spaces of gerotor components 10 and 11 (Fig. 5). The chamber attains maximum volume after

180° of rotation where the inlet port and the intake phase end. Further

rotation causes this chamber, in traversing the next sector, to reduce

in volume. Because there is no vent in this sector of cavity 14, the

combustible mixture is compressed. The compression phase ends after

the chamber travels some degrees less than 360°, where, nearing its

minimum volume, it reaches arcuate passageway 26 and is vented

through to cavity 15. Coincidentally, a chamber formed by gerotor

components 12 and 13 starts to enlarge at the passageway from which

the charge is received.

The charge is fired by spark plug 30 approximately at the time of

the compression chamber's minimum volume. Spark synchronization is

not critical since some of each compressed charge remains in passageway 26 in a state of combustion and serves as a pilot to ignite the next

charge.

Tech. Note 295, October 14, 1966

4
Passageway 26 is positioned so as to be closed on the entry

side by the trailing tooth of gerotor component 11, which has bounded

the compression chamber before the latter' s reaching minimum volume.

As combustion proceeds, and tends to increase the charge's pressure,

it is relieved on the exit side of the passageway to the opening chamber

formed by gerotor components 12 and 13. This is the start of the expansion phase (Fig. 6) which continues until the chamber reaches the

point of maximum enlargement after about 180° of rotation. Here the

chamber starts venting at the beginning of the exhaust port 27 (Fig. 3).

The exhaust phase proceeds while the chamber is reducing for approximately the 180° remainder of this rotational cycle.

In this way, a four-phase cycle for each charge is completed

after two revolutions. Each phase is performed in an approximate 180°

increment; intake and compression in a chamber bound by gerotor

components 11 and 12, and expansion and exhaust in a cooperating

chamber bound by gerotor components 12 and 13.

Tech. Note No. 295, October 14, 1966

5
HIGH TEMPERATURE PLATINUM RESISTANCE THERMOMETER

Leslie A. Guildner

Richard L. Anderson

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Tech. Note No. 295, October 14, 1966
HIGH TEMPERATURE PLATINUM RESISTANCE THERMOMETER

Leslie A. Guildner

Richard L. Anderson

This is a high precision platinum resistance thermometer capable of

operating above the upper temperature limit (approximately 630° C)

of conventional platinum resistance thermometers.

As shown in Fig. 1, 'the thermometer comprises a coil form 10, a

plurality of insulators 11 and links 12, a sheath 13, and header 14,

The coil form 10, shown in detail in Figs. 2, 3, and 5, is a tubular ceramic member of "C"-shaped cross section. A plurality of

longitudinally-extending holes 15 are provided in the form 10, and a platinum wire 16 is loosely threaded through the holes 15 from one end

of the "C" to the other end thereof. By this design, the platinum

wire 16 is supported in a strain-free manner within a small space, and

the ends of the wire 16, where the largest voltage drop occurs, are well-insulated from each other by the gap or break in the 'C" -shaped

form 10.

The ceramic material employed for the form 10 should have the

following characteristics at elevated temperatures (above 630 °G),

The resistivity of the ceramic should be high to provide good electrical

insulation between adjacent parallel portions of the wire 10, and

between the wire 16 and sheath 13; the dimensional stability of the

ceramic should be high to avoid stretching the wire 16; the thermal

conductivity and thermal diffusivity of the ceramic should be high to

minimize temperature gradients along the wire 16 and to minimize the

time required to attain a steady state with respect to the surroundings;

and, the material should not contaminate the platinum wire 16, nor

require the presence of oxygen to prevent contamination thereof. This

combination of characteristics is approached in sintered high-purity

beryllium oxide, which is the preferred material for constructing the

form 10.

Tech. Note No. 295, October 14, 1966

7
Referring again to Fig, 2, it will be seen that the ends of the

platinum wire 16 are each connected to two leads 17, 18 (the current and

potential leads) in the conventional manner. These leads 17, 18 are carried by the insulator 11, which advantageously is identical to the

coil form 10. As shown in Fig. 4, the leads 17 and 18 are disposed in

pairs of holes on opposite sides of the air gap in the insulator, to

obtain the maximum electrical insulation between the two pairs of leads.

The coil form 10 and insulator 11 are connected by a link 12,

Fig. 2, comprising a rod of a low thermal conductivity ceramic material,

such as sintered high-purity aluminum oxide. The use of such a material

for the link 12 minimizes the conduction of heat along the axis of the

thermometer. Fig. 1. To attach the link 12 to the members 10 and 11,

there are provided t wo ceramic pins 19 which extend through matching

transverse holes in the members 10, 11 and the link 12.

From the foregoing it will be seen that this thermometer is easily

assembled using units of only three ceramic parts, namely, the "C"-

shaped members (10 or 11), the links 12 and pins 19. These elements

are linked together to form an assembly of any desired length, with the

assembly having sufficiently flexibility to avoid fracturing of the

ceramics upon slight bending of the sheath 13, Fig. 1. The selected

ceramic materials and shapes thereof are such that the thermometer has

favorable electrical and thermal behaviors.

Tech. Note No. 295, October 14, 1966

8
DYNAMIC ANALOG CORRELATION SYSTEM

Robert W. Hubbard

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Tech. Note No. 295, October 14, 1966

9
DYNAMIC ANALOG CORRELATION SYSTEM

Robert W. Hubbard

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FROM

FlOi

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SUMMING

CIRCUIT

DIFFERENCE

CIRCUIT

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SERVO

AMPLIFIER

SERVO

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CIRCUIT

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CIRCUIT

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CIRCUIT

AVERAQING

CIRCUIT

2„Z .u^Z^Z

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a^dr i-b^crS'y - ZabcTx'xy

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61

VARIABLE

ATTENUATOR.

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DIFFERENCE

CIRCUIT

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RECORDER

35

Tech. Note No. 295, October 14, 1966

10
DYNAMIC ANALOG CORRELATION SYSTEM

Robert ^A/. Hubbard

This system may be used to obtain the correlation between two timevarying signals. This relationship is found continuously and is normalized automatically.

Consider two random or periodic signals, both functions of time,

2 2 x(t) and y(t) and both mean zero signals Let a and a represent the X y

variances of x and y, respectively, and a and a the standard deviations. Then, the variance of the difference of x and y and the variance

of their sum are as follows:

(J' =a^ +a^ - 2paa (1) x-y X y X y

(7^^ x+yx+y = a^ ^a^ + 2pcT ^xya (2)

where

(J P = XV

a cr X y

' correlation coefficient.

The sum and difference of the variances in equations (1) and (2) are:

{<jI +y) + {G^ x-y) =2(aJ +jf) (3)

(a^^) - (a^ ) - 4pa a = 4a . (4) x+y x-y X y xy

Tech. Note No. 295, October 14, 1966

11
2 2

If the two signals x(t) and y(t) have the property a - Q over the

averaging period of Interest, then (3) becomes

2(a^ +0-) = 4a a (5) X y X y

^

'

and the ratio of equations (4) and (5) yield the desired correlation

coefficient

4a

JCY_

4a aX y

--P. (6)

In the present system, the variances of x and y are computed and

a servo loop is used to hold the variances equal over a selected averaging period. Signals ax and by, where a and b are amplification factors, are derived from the latter loop and are used to obtain the relationships

expressed in equations (3) and (4). A self-balancing servo loop is then

employed to compute the ratio of equations (4) and (5). Thus, a signal

that represents the correlation coefficient (p) is obtained, and Is recorded

in analog form.

The function ( p) may thus be computed and recorded as a function

of time (t) with fixed time lag (t), or as a continuous function of ( t ) for fixed data sample lengths. A dynamic time lag is translated to the

computer through the use of a special magnetic tape transport mechanism.

Tech. Note No. 295, October 14, 1966

12
With reference to Fig. 1, the time lag storage bin and the main

storage bin are indicated by 18 and 19, respectively. During recording

the arms of switches 20 and 21 are thrown to the left in Fig. 1, and

magnetic tape 22 is driven by capstan 23 and is guided by capstan 24

and rollers 25 past read-record heads 26 and 27. The signals to be

correlated, signals x' and y', are then recorded simultaneously on

separate channels of tape 2 2. During play-back, the arms of switches 20

and 21 are thrown to the right, the magnetic tape is driven by capstans

23 and 24, and heads 26 and 27 generate signals x and y, respectively.

This arrangement is used to introduce a dynamic time lag of signal y

with respect to signal x. When the magnetic tape is taut the time lag

Is zero, and when capstan 23 is driven at a slower speed than capstan

24 the tape piles up in container 18 and the time lag increases linearly

with time.

Signals x and y are applied to the variable gain operational amplifiers 30 and 31 whose outputs are fed to squaring circuits 32 and 33 to

2 2 2 2 obtain signals a x and b y . The latter signals are transmitted through

2 2 2 2 averaging circuits 34 and 35, developing signals a a and b o , which

are applied to differential servo amplifier 36. The output of this amplifier controls servo motor 37 which in turn controls the gain of amplifiers

2 2 2 2

30 and 31 in such a manner that a a is maintained equal to b a over X y

the averaging period selected for circuits 34 and 35. It should be noted

2 2 that a a anc X

respectively.

2 2 2 2

30 and 31 in such a manner that a a is maintained equal to b a over X y

)d selected for ci

2 2 2 2 that a a and b o are equal to the variances of signals ax and by.

Tech. Note No. 295, October 14, 1966

13
Signals ax and by, developed by amplifiers 30 and 31, are applied to summing circuit 40 and difference circuit 41 in Fig. 2. Signal ax + by, the output of circuit 40, is sent through squaring

2 circuit 42 to generate signal (ax + by) , which is applied to averaging

2 2 2 2 circuit 43. The output of the latter circuit is signal a a + b J + 2aba X y xy

and is applied to the sum and difference circuit 44. Likewise, signal

(ax - by) appears in the output of difference circuit 41 and is trans2 mitted through squaring circuit 47 to develop signal (ax - by) , which

is applied to averaging circuit 48. The latter circuit develops signals

2 2 2 2 a a + b a - 2aba , which is sent to circuit 44. X y xy

The sum and difference circuit 44 provides a sum signal

2 2 2 2 2(a cr + b C7 ), that is fed to differential servo amplifier 50 and a X y

*^ difference signal ^ 4abor , that is fed to variable attenuator 51. The

xy

gain of the attenuator is l/K. The output of amplifier 50 is applied to

servo motor 52 which controls the shaft of attenuator 51 in such a way

that the sum and difference output signals of circuit 44 are maintained

equal. Hence

Since

l/K (4aba ) - 2(a^a^ +b^(7^).

xy X y

2 2 ,22 a a = b g X y

1/K(4aba ' ) = 2(2 a^a^) = 4 (aa • acTJ = 4 aba a

xy XX x' X y

v xy

a aX y

Tech. Note No. 295, October 14, 1966

14
D. C. source 53 is connected across center-tapped potentiometer

54, Servo motor 52 controls the arm of the potentiometer to generate a signal across the arm to ground that has a magnitude dependent upon

the value of K. The latter signal, representing the correlation coefficient, is recorded as a function of time by means of recorder 55.

Tech. Note No. 295, October 14, 1966

15
COMBINATION METERING AND SAFETY VALVE FOR FILLING SONDE

BALLOONS WITH HYDROGEN

William W. Richardson

50N0a

BALLOON

CONTROL ^2Z

PANtL

BKPLOSION-PROOf- "^ SOLENOID

SUNCTION BOX \JP\L\/E:

HWDKOOBN

TAKIK

Tech. Note No. 295, October 14, 1966

16
COMBINATION METERING AND SAFETY VALVE FOR FILLING SONDE

BALLOONS WITH HYDROGEN

William M. Richardson

Tech. Note No. 295, October 14, 1966

17
COMBINATION METERING AND SAFETY VALVE FOR FILUNG SONDE

BALLOONS WITH HYDROGEN

William M. Richardson

CONTROL P/^NEL JUNCTION BOXFiq:3

'-d'-

Tech. Note No. 295, October 14, 1966

18
COMBINATION METERING AND SAFETY VALVE FOR FILUNG SONDE

BALLOONS WITH tlYDROGEN

William M, Richardson

This valve automatically meters a predetermined amount of hydrogen

gas to a sonde balloon, and interrupts the flow in the event that the

balloon bursts before filling.

In Fig. 1, the sonde balloon 10 to be filled with hydrogen is

attached to a filling nozzle 11 which is connected by a flexible tube 12

and solenoid-operated, explosion-proof valve 13 to a tank 14 of hydrogen gas. The nozzle 11 is physically restrained by a cord 15 that is

tied to a short column 16. This short column 16 telescopically slides

within a longer column 17 carrying a selected number of weights 18.

As will be described below, the movement of the columns 16 and 17

operates electrical switches which are brought out to an explosionproof junction box 19. The junction box 19 is connected by explosionproof conduits 20 and 21 to the solenoid valve 13, and to a control

panel 22 located in a remote bunker. The control panel 22 is connected

to an ac power line by a conduit 23, and has an on-off switch 24, a push-button switch 25 and indicator light 2 6.

As shown in Fig. 2, the columns 16 and 17 are each coaxially

disposed on a tube 30 that projects from the junction box 19. The

tube 30 is sealed at its upper end 31, and contains two magneticallyoperated reed switches 33 and 34. The contacts of the lower reed

switch 33 are normally held closed by a pair of permanent magnets 35

that are fitted into holes drilled into the long column 17. The contacts

of the upper reed switch 34 are normally open, and are closed when the

short column 16 is lifted, as indicated by the dashed lines 36, causing

a pair of permanent magnets 37 disposed in the column 16 to assume

positions adjacent the reed switch 34.

Tech. Note No. 295, October 14, 1966

19
Referring to Fig. 3, it will be seen that the switches 33 and 34 are connected in series with a relay coil 40 and a low voltage dc source

41, The contacts 42 of the relay 40 serve to close the solenoid coil 13

across the ac input line, and thereby open the solenoid valve and allow

hydrogen from tank 14 (Fig. 1) to flow to the sonde balloon 10.

In the operation of the present valve, the balloon 10 is attached

to the filling nozzle 11, and a number of weights 18 corresponding to

the desired lift of the balloon are placed on the column 17 (the weights

of the columns 16 and 17 are included in the total weight. The main

switch 24 is then closed, and the push-button switch 2 5 is depressed.

As shown in Fig. 3, this switch 2 5 is in parallel with the normally-open

upper reed switch 34. Hence the manually-closed switch 25 and the

normally-closed lower reed switch 33 complete the circuit for relay 40,

causing the solenoid valve 13 to open and permit the hydrogen to flow

into the balloon 10. The opening of the solenoid valve 13 is indicated

by the lighting of the lamp 26, see Figs. 1 and 3. With push-button 25 held depressed, the balloon partially fills

and exerts sufficient buoyancy to lift the short upper column 16. The

column 16 is relatively light, and easily lifted to the raised position

indicated by dashed lines 36 of Fig. 2. In this raised position, the

magnets 37 close the contacts of the reed switch 34, so that the relay

40, Fig. 3, is then energized through switches 3 3 and 34, The pushbutton switch 2 5 thus may be released by the operator, and the balloon

will continue to be filled with hydrogen.

Tech. Note No. 295, October 14, 1966

20
When the balloon 10 has received sufficient hydrogen to lift the

columns 16, 17 and weights 18, the column 17 will move upward along

the tube 30 a very small amount. This upward movement will lift the

magnets 35 from adjacent the closed lower reed switch 33, causing the

switch to open. As can be seen from Fig. 3, opening of switch 33

opens the circuit of relay 40, and thus opens the circuit of solenoid

valve 13, In this manner, the flow of hydrogen gas is automatically

terminated when the balloon receives the predetermined amount of gas.

The valve thus provides an automatically-metered filling.

In addition, the valve provides an automatic termination of the

hydrogen flow in the event that the balloon bursts during the filling

process. As will be recalled, the operator manually depresses the

switch 25 until the balloon raises the upper column 16, after which

the switch 2 5 is released. It will readily be apparent that bursting of

the balloon would cause the column 16 to drop, which i n turn would

cause the magnets 37 to drop from adjacent the reed switch 34, and

thereby open the switch 34. From Fig. 3, it will be seen that the

opening of switch 34 (switch 2 5 being open) would release relay 40 and

therefore cause the solenoid valve 13 to close. The hydrogen gas would

thus be closed at the solenoid 13, rather than continue to flow to the

nozzle 11 and balloon.

In Fig. 2, the columns 16 and 17 are illustrated as being in

sliding contact with the tube 30 containing the reed switches 33, 34.

To minimize the friction, the columns may each be provided linear

ball-bearing bushings.

Tech. Note No. 295, October 14, 1966

21
There is an alternative method for initiating the flow of hydrogen

to the balloon until the balloon can raise column 16. In this alternative

method, the column 16 is provided with any suitable mechanical latching mechanism (not shown) for holding the column 16 in the raised

position 36, Fig. 2. The operation is then as follows: The switch 24

is turned on, and the operator approaches the balloon and latches the

column 16 in the "up" position. This closes switch 34, which actuates

the relay 40 and solenoid 13, permitting the gas to flow into the balloon.

When the operator observes that the balloon has received sufficient gas

to hold the column 16 up, he unlatches the column 16, so that the

column is free to drop in the event of a balloon burst. "WTien the balloon

fills, it tends to lift column 17 and open switch 33 and therefore solenoid

13, as described previously.

Tech. Note No. 295, October 14, 1966 »u.s. government printing off,ce= 1966-251-020/32

22



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