US2142254A - Electric circuit controlled by light cells - Google Patents

Description

T. J. NUNAN Jan. 3, 1939.

ELECTRIC CIRCUIT CONTROLLED BY LIGHT CELLS Original Filed March 5, 1935 2 Sheets-$11ee1 1 T. J. NUNAN Jan. 3, 1939.

ELECTRIC CIRCUIT CONTROLLED BY LIGHT CELLS Original Filed March 5, 1935 2 Sweats-Sheet 2 m L wm A m W N AN 0 a 1 R \L Y \L Y L Y i Y \L Y R Y k W 2 Y \L Y k Y \N A Y aint INVENTOR. M

.ATTORNE 1 u Patented Jan. 3, 1939 PATENT OFFICE ELECTRIC CIRCUIT CONTROLLED BY LIGHT CELLS Thomas J. Nunan, Summit, N. J., assignor to The Clark Thread Company, Newark, N. J., a corporation of New Jersey Original application March 5, 1935, Serial No. 9,428. Divided and this application March 4,

1937, Serial No. 128,997

7 Claims.

This invention relates to a novel and improved form of electric circuit, more particularly one controlled by light cells. This application is a division of my copending application Ser. No. 9,428, filed March 5, 1935, and the invention Will be described in connection with the apparatus shown in the parent application. In the annexed drawings, I have shown a selected embodiment of the invention, and in those drawings:

Fig. 1 is a vertical face View of an apparatus with which the invention may be employed;

Fig. 2 is a detailed View substantially on the line 2-2 of Fig. 1;

Fig. 3 is a view substantially on the line 3--3 of Fig. 1;

Figs. 4 and 5 are views showing diagrammatically certain parts appearing in Fig. 1 when in different positions;

Fig. 6 is a wiring diagram of so much of the circuit as is necessary for an understanding of the invention.

The invention is shown as used in connection with a device for testing thread to the breaking point, successive lengths of thread being thus broken, but it is to be understood that the invention has other uses.

Referring first to Fig. 1, I have shown therein a thread cylinder l forming a source of supply for thread to be tested and from which the thread 2 passes through a tension device 3 of any suitable construction and is then carried by a rotary frame 4 to a clamp 5 supported upon a bracket 6 secured to a movable part I of a scale 8. The scale is selected as a suitable form of indicator or measuring instrument and may be of any of the well-known forms which may be found suitable for the purpose. Therefore the details of the scale mechanism will not be described except as they are of interest in understanding the in vention. The indicating part of the measuring instrument may be omitted' entirely for some purposes, and therefore the word indicator is used merely for convenience of expression.

For the purpose of convenience I shall refer to the clamp 5 as the indicator clamp, since it moves with the indicator.

The frame 4 is rotatably mounted about its axis 9 on a suitable support Ill, here shown in the form of a panel extending upwardly from a base II, and is operated in a clockwise direction, as viewed in Fig. 1. The rotation of the frame 4 is an intermittent one, which may be caused by any suitable means, the details of which are not necessaryto an understanding of the invention claimed herein and which consequently have been omitted.

Rotatably mounted upon the panel i0 is a rock shaft I2 having on the front of the panel a lever l3 secured thereto, and upon the outer end of this lever is a clamp l4 which, for the sake of convenience, I shall refer to as the breaking clamp. The lever I3 is periodically depressed by means of a cam which is operated by a suitable means which, not being necessary to an understanding of the invention, will not be described.

The two clamps 5 and I4 are controlled by means of solenoids l6 which are operated at proper intervals so that, as the frame 4 rotates, it may place within the clamps 5 and I4 a length of thread 2, after which the solenoids are operated to securely clamp the thread in position. When thus clamped, the clamp I4 is stationary and then the cam I5 depresses the lever l3, carrying with it the clamp l4 and thus pulling the bracket 6 downwardly and causing a downward pressure on the movable part of the scale. This in turn will cause movement of the pointer 66 of the scale over the scale face 66'.

Movement of the pointer causes operation of suitable recording apparatus, shown generally at H, by means of circuits which in turn are controlled by light-sensitive elements such as photoelectric cells indicated at 13a and 13b adapted to be acted upon by lamps 14a, and 14b, respectively. The cells and lamps are of known or any desirable construction, and their details are not necessary to an understanding of the invention claimed herein.

Secured to the pointer 66 is a shutter 16 which passes between the cells and lamps and which has therein a plurality of holes 11 spaced apart a distance corresponding in number to the units of force shown on the indicator. The shutter is concentric with the center of movement of the pointer, and the arrangement is such that the holes 11 will pass successively between the lamps and cells. The light from either lamp may pass through any hole in the shutter to the cell corresponding to that lamp.

In the parent application and divisional parts thereof I have more fully described and claimed the detailed operation of the testing device, the circuits operated thereby, and the manner in which those circuits operate the recorder. For the purpose of the present application, it will be suflicient to say that therecorder is operated by impulses caused in the controlling circuits by action of light from the lamps upon the photoelectric cells. It is well'known that the action of light on a photo-electric cell will cause an impulse to be sent along a circuit in which that cell is placed, and such impulses are used to operate the recorder.

I have found that for some types of testing apparatus where the units to be measured and recorded are relatively small, or where for any other reason the holes T! in the shutter, I5 are placed close together, and then a vibration occurs which will disturb the relation of the shutter to the lamp and cell, such vibration may cause the shutter to flutter enough to send impulses, by changing the quantity of light reaching the cell.

In this embodiment, I provide the shutter 16 with a hole 71 for each two ounces or units of measurement, thereby cutting down the number of holes by half. The two lamps and their respective cells are so spaced apart lengthwise of the shutter that when one lamp is shining through one of the holes H, the other lamp has its beam of light directed against an opaque part of the shutter half way between two adjacent holes. In this instance, the center to center spacing of the lamps and cells, respectively, is of the center to center spacing of the holes.

By means that will be explained later, when the scale pointer 66 indicates zero, neither lamp 74a nor 1412 will be lighted, nor in registry with one of the holes, but the end hole Tll is disposed between the beams of light from the two lamps, as plainly shown in Fig. 6.

Now as the pointer 66 moves from zero to l on the scale face 6?, both lamps are lighted, by means to be described later, and the next to the last hole Tl-2 will come into registry with the beam of light from the lamp Mb, as shown in Fig. 4, and cause this beam to act upon the cell 132). However, the end hole Tl1 will not have reached a position to register with the beam of light from the lamp Ma, as shown in Fig. 4.

Then, as the pointer moves to 2 upon the scale face, the end hole l'i--1 will be brought to a position to register with the beam of light from the lamp 14a and the next hole 77-2 will pass out of registry with the beam from the lamp Mb, all as shown in Fig. 5. This operation will be repeated, first one hole coming into registry with one beam of light and then the other hole coming into registry with the other beam of light, either one lamp or the other acting upon its cell for each unit of measurement.

Since the circuit which is now to be described may be used with a wide variety of appliances, it is sufiicient to say that electric current for the lamps may be supplied from any suitable source, here shown as two conductors H6 and ii! and a transformer H8, to the secondary of which are connected conductors H9 and i2ii for supplying current to the lamps. 7

Each cell is placed in the input circuit IZdal25a or I2 3bi25b of an amplifier I221; or 221), respectively. These amplifiers are connected in parallel toand receive current from the conductors l2! and I23.

In the embodiment being described, I use a double switch indicated generally by the numeral 99 and controlled by the position of the .bracket 6. switch comprises four spring contacts in what is known as a break-make assembly, these 7 contacts being identified as 209, 2H3, 2| and U2. When the pointer 66 is at zero, the various contacts have the relation shown in Figs. 2 and 6, namely, the two contacts 209 andZlG are out of engagement with each other, and the contacts 2!! and H2 are in engagement with each other, in which position they are held by the bracket, as shown.

Now as the bracket 6 is moved downwardly under the tension of the thread before it breaks, the contact 2! 2 will move out of engagement with the contact 2! i, and the contact 2139 is brought into engagement with the contact Zlil, the contacts 209 and H2 moving together under their spring actions and through the arrangement of insulating spacers 2l3. Therefore, as soon as tension on the thread is suficient to move the bracket 6 downwardly, the result is to open one circuit and close another. The circuit controlled by the contacts 2! l--2 i2 is a shorting circuit and includes a contact 2H5 centrally disposed on an armature 2E6 adapted to be operated by either one of the magnets, 2H or 2H8 connected respectively in the output circuits of the amplifiers I221) and l22a.

'Ihis contact H5 is between and may contact with either one of two spring contacts 2 l9 or 220, both connected to a conductor 22l which leads back to the contact 2|2. The conductor 2 i4 is in turn connected through a battery 222 to the conductor i33, and the conductor 22! is connected directly to the conductor 3 3. The conductors E33 and EM are shown as connected to a magnet E35 controlling the operation of certain switches I36 and N31. The magnet is taken as an example of a device to which impulses are to be sent by operation of the shutter, and the device may be used to operate any desired mechanism, such, for example, as a recording apparatus which is shown as being thus operated in said copending application, Ser. No. 9,428.

Connected to the circuits of one of the cells, here shown as the cell 13a, are conductors 223 and. 224 containing two high resistance units 225 and 226, and the circuit through these resistances comprises a switch 22? which is adapted to be closed by the shutter or pointer when at zero position, as indicated in Fig. 1,

Assuming that the pointer is at zero, then the circuit through the lamps is broken between the contacts 239 and 2H], while the contacts 211 and 2 l2, and 255 and M9, are in engagement, respectively, The various holes in the shutter occupy the positions shown in Fig. 6 and the magnets 2i? and M8 are deenergized.

As soon as the pointer and shutter have moved a distance corresponding to one unit of measurement, then the next to the last hole Tl2 will come into registry with the lamp i l-b as previously described, and as shown in Fig. 4, and will thus affect the cell i319, energizing the magnet 2 I l and attracting the armature 2H5 to that magnet and away from the magnet 258. This will break the circuit between the contacts 2! 5 and 2i9 and after a very short interval of time will make a circuit between the contacts 2E5 and 228. This action will momentarily deenergize the magnet i535 by breaking the circuit through the battery 222 and the magnet, thus permitting the switches i" and i3? toclose. When, however, the contact 2E5 engages the contact 22!], the circuit is again completed through the magnet E35 and the battery 222, again opening the switches !36' and EM, The result is the sending of an impulse to the magnet l 35 and then the'immediate breaking of the circuit of that magnet, so that nofurther impulses may be sent no matter how much the shutter may vibrate. 'Shortly thereafter the cirsuit is again closed, but in the meantime the shutvter hasmoved sufliciently so that no hole is in registry with a beam of light or else the shutter has ceased vibrating.

The two magnets 21'! and 2! are so constructed that the armature will stay in position against the core of the magnet last energized. Now assuming that the shutter and pointer move a distance corresponding to another unit of weight, the last hole '|'|1 will come in registry with the lamp 14a and cell 13a, as shown in Fig. 5, and thus energize the magnet 2|8, which will cause an impulse to be sent to the magnet :35 in the same manner as just described above, the magnet 2i! having been de-energized because of the movement of the shutter to interrupt the beam of light which has previously caused that magnet to be energized.

These operations will be repeated as each hole comes into registry with one of the lamps and its corresponding cell until the thread breaks, and the registry of a hole with a lamp results in only one impulse.

When the thread breaks, the bracket 6 will rise to the position shown in Fig. 6, opening the lamp circuit by moving the contact 209 out of engagement with the contact 2H) and closing the shorting circuit by engagement of the contacts 2!! and 2|2.

After the breaking of the thread, the pointer is temporarily held at the position which it occupied when the break took place, after which it is released and allowed to return to zero by the normal means provided by the scale for that purpose. Here again the means for controlling the operation of the pointer after breaking of the thread is not necessary to an understanding of the invention claimed herein and so will not be further described.

While the pointer and shutter are returning to zero, the lamps will thus be extinguished and no light will reach the cells from the lamps and thus no impulses will be sent. As the shutter and pointer reach zero, the switch 221 will be closed, short circuiting the input to the amplifier I22a, causing an impulse of current to flow through the magnet 2| 8 in the same manner as if light reached the cell 13a, and thus causing the armature 2| 6 to return to the position indicated, if not already there. If already there, the short circuiting has no effect.

The above operation is. used in order to insure that the armature 2|6 shall always be at the indicated position when the pointer is at zero.

Assuming that the armature 2H5 is moved from engagement with the core of the magnet 2|! to engage with the core of the magnet 2| 8, or, in other words, to the position indicated, as just described, then that act would cause an impulse to be sent to the magnet I35 unless some means were provided to prevent it. Such means is pro vided by the shorting circuit comprising the conductor 2M, contacts 21! and 212, and conductor 22l, thus providing a short circuit between the conductors 214 and 22l and avoiding the sending of any impulse to the magnet I35 through the battery 222.

While I have shown the invention as embodied in a specific form, it is to be understood that various changes in details may be made without departing from the scope of the invention, as defined by the appended claims.

I claim:

1. In combination, an electric circuit including an element adapted to be operated by electrical impulses sent through said circuit, a light-sensitive cell, a lamp so placed that a beam of light therefrom may strike said cell, a shutter adapted to move between said lamp and cell and having a hole therein through which said beam may pass to said cell as the hole is moved through said beam, means operated by the action of the beam on the cell to cause an impulse in said circuit when said beam passes through said hole during said movement of the shutter, and means in said circuit limiting the number of impulses to one impulse for each movement of said hole through said beam of light.

2. In combination, an electric circuit including an element adapted to be operated by electrical impulses sent through said circuit, a light-sensitive cell, a lamp so placed that a beam of light therefrom may strike said cell, a shutter adapted to move between said lamp and cell and having a hole therein through which said beam may pass, and means operated by the action of the beam on the cell to open and close said circuit momentarily to cause an impulse in said circuit to operate said element.

3. In combination, an electric circuit including an element adapted to be operated by electrical impulses sent through said circuit, a light-sensitive cell, a lamp so placed that a beam of light therefrom may strike said cell, a shutter adapted to move between said lamp and cell and having a hole therein through which said beam may pass, and means operated by the action of the beam on the cell to open and close said circuit momentarily to cause an impulse in said circuit to operate said element, said means causing only a single opening and closing of said circuit, thereby insuring the causing of a single impulse only.

4. In combination, an electric circuit including an element adapted to be operated by electrical impulses sent through said circuit, a switch in said circuit comprising two spaced contacts and a movable contact adapted to engage either one of the spaced contacts to close said circuit, said movable contact normally being in engagement with one of said spaced contacts, an armature operatively connected to said movable contact and having two magnets associated therewith, energizing of one magnet causing the movable contact to engage one of the spaced contacts and energizing of the other magnet causing the movable contact to engage the other spaced contact, means to render said lamp inoperative, and means to then return the shutter to initial position, whereby upon said return movement the lamp will not affect the cell.

5. In combination, an electric circuit including an element adapted to be operated by electrical impulses sent through said circuit, a switch in said circuit comprising two spaced contacts and a movable contact adapted to engage either one of the spaced contacts to close said circuit, said movable contact normally being in engagement with one of said spaced contacts, an armature operatively connected to said movable contact and having two magnets associated therewith, energizing of one magnet causing the movable contact to engage one of the spaced contacts and energizing of the other magnet causing the movable contact to engage the other spaced contact, a circuit for each magnet including a light-sensitive cell, a source of light adapted to direct a beam of light to each of said cells, a shutter adapted to cut off said beams from said cells and having holes therein so arranged that a beam of light may pass to first one cell and then the other as the shutter moves past the cells, means czi to thus :move the shutter, lfor the purpose set forth, a shorting circuit connected across said movable and spaced contacts and having a switch therein, means to move the shutter back to initial position after its operation,- and means to open saidswitch at the beginning of the operation and to close it at the end thereof, for the purpose set forth.

6. In combination, an electric circuit, two 'ohotoeiectriccells, each having a lamp associated therewith and each adapted to control said circuit, and a shutter movable between said cells and their associated iampsand having a plurality of holes therein, the spacingof the lamps and cells, respectively, being equal to of the spacing of said holes.

THOMAS J. NUNAN.

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