US817251A - Automatic stereopticon apparatus. - Google Patents

Automatic stereopticon apparatus. Download PDF

Info

Publication number
US817251A
US817251A US25752505A US1905257525A US817251A US 817251 A US817251 A US 817251A US 25752505 A US25752505 A US 25752505A US 1905257525 A US1905257525 A US 1905257525A US 817251 A US817251 A US 817251A
Authority
US
United States
Prior art keywords
switch
light
circuit
slide
lantern
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.)
Expired - Lifetime
Application number
US25752505A
Inventor
Marcus H Killen
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.)
MARK L KILLEN
Original Assignee
MARK L KILLEN
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 MARK L KILLEN filed Critical MARK L KILLEN
Priority to US25752505A priority Critical patent/US817251A/en
Application granted granted Critical
Publication of US817251A publication Critical patent/US817251A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • GPHYSICS
    • G03PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03BAPPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR
    • G03B23/00Devices for changing pictures in viewing apparatus or projectors
    • G03B23/02Devices for changing pictures in viewing apparatus or projectors in which a picture is removed from a stock and returned to the same stock or another one; Magazines therefor
    • G03B23/06Devices for changing pictures in viewing apparatus or projectors in which a picture is removed from a stock and returned to the same stock or another one; Magazines therefor with rotary movement

Definitions

  • his invention relates to ma ic lanterns and stereopticon apparatus, and as particular reference to mechanisms for automatically c ⁇ ntrollingthe operation of a device of ⁇ this class so that all of the various mani ulaf'matically starting the device and causing the saine to operate automatically to present a series of pictures and ⁇ finally to automatically cease to operate after the expiration of a certain predetermined period of time, to provide improvedelectrically-controlled mechanisms for accomplishing the foregoing 'obiects, to rovide an improved form of slideholding evice whereby each slide of a series may be independently focused and whereby other slides may be readily substituted kfor slides already focused without disturbing the focusing adjustment, and.
  • s ring mechanism normally urging the rotation of said member
  • mechanism for intermittently stpiping such rotation to successively bring i erent slides into ositions of alinement with the lenses of t e lantern time-controlling mechanism for controlling the successive movements of the slide-holding member and for extinguishing the light of the lantern during periods in which the change of slides is taking place, and mechanism for starting the device at a certain hour of the day and stopping the operation of the same after the expiration oi' a certain predetermined interval of time.
  • the plate-holding member 5 is in thefor'm of a wheel mounted on a horizontally-disposed shaft 6, which is journalecl in adjustable bearings 7 in the supporting-fr? me 8.
  • the member 5 has a series of equally-spaced plateholders 9 secured to its periphery.
  • the plate-holders 9 lie in the same plane with each other and are arranged to pass edgewise through the slide-space 10 of a lantern 11, mounted at one side of the supporting-frame.
  • the member 5 is provided with spring mechanism adapted to normally urge its rotation, said mechanism being indicated by the pinion 12, the gear 13, and the coiled spring 14.
  • the rotation of the member 5 is controlled by an escapement device which consists of an electromagnet 15, having an armature 16, mountedto move intoand out of the path of the slide-frame.
  • the armature 16 is normally urged into position for engaging the advancing edge of one ci the .frames 9, as is seen in Fig. .1.
  • frame 2O is adjustable against the pressure of the clips 19 by means of four adjustingscrews 21 at its respective corners.
  • the frame 20 serves to prevent direct contact between the set-screws 21 and the glass of the lanternslide, and thus prevents unequal strain upon theglass and consequent tendency to break.
  • the function of the screws 21 is to permit of certain ladjustment of the slide to bring it into exact focus with the lenses of the lantern.
  • the light of the lantern is an incandescent electric light 22 and receives its energy from circuit is controlled by a knife-switch 23, which is respectively opened and closed by The operation of the various mechanisms 2.o which have been described is controlled by Y means of a time mechanism, which is indicated by the clock-dial 26 in Fig. 1.
  • This clock is provided with an hour-hand 27, .which is adapted to have electrical contact with two contact-buttons'28 and 29, which are otherwise insulated from the clock, but are adjustable around the dial, so as to be engaged bythe hand 27 when such hand arrives at a desired position on the dial.
  • the buttgns 28 and 29 are adjusted to different positions by inserting their shanksin the small apertures surrounding the dial.
  • the clock is also provided with a seconds-hand 30, l which makesv a conplete revolution every 3 5 minute and which at certain intervals of each revolution successively cornes into electrical contact with buttons 31, r32, and 33.
  • the circuit L supplies current for the light 22 of the lantern and is otherwise independentof the controllingcircuits.-
  • the circuit L is controlled bythe knife-switch 23.
  • the circuits A, B, C, and F are controlled by means of a switch 34, which is opened by the solenoid and closed by the solenoid 36. All of the circuits A, B, C, D, E, and F receive current from a battery 37.
  • the conductor 38 connects directly with the clockcasing, which is in electrical circuit with the remaining parts of the time mechanism of the lclock and forms a part of 'each of the controlling-circuits.
  • the contact-buttons 28, 6o 29, 31, 32, and 33 are all-insulatedrom the i clockwork mechanisn l and have electrical communication therewith only when the respective hand is in contact therewith.
  • the circuit D which controls the solenoid 36, is in circuit with the contact-hutten 2g an electric circuit, (indicated at L.) This' 'point 29 1s also adjusted to the time at which Iwound and set and allowed to run, the
  • the circuit E oplerates the solenoid 35 Jfor opening the sWitc 34 when the hand 27 7o is in contact with the button 29.
  • the circuit F controls the solenoid 24 and opens the knife-switch 23 for cutting out the light 22 when the and 27 is in contact with the button 29.
  • he circuit A is closed when the seconds-hand 30 is in contact with the button 31 and operates the solenoid 24 vfor extinguishing the light.
  • the circuit C controls the magnet 15 and operates thearmature 16 of the escapement-pawl 39.
  • the circuit B 8o when closed by the seconds-hand 30 turns on the light 22.
  • a lantern-slide is inserted into each of the frames when said frame is in the position 8 5 9 at the right of Fig. 1.
  • the slide is inserted in an upright position and will therefore Be inverted when itcomes into alin'ement with the lenses of the lantern, as is ,usual in d evices of this class.
  • the operator then shifts 9o the button 28 to a position on the periphery of the dial of the clock to correspond to the time at'which it is desired to have the display of ictures commence'.
  • the contactthe exhibition -isito cease'.
  • the clock is then switches 34 and 23 being opened.
  • the hand 30 next arrives at the contact-point 32, completing the cirpawl 39 lfor an instant to permit the spring to bring the next succeeding slide intov alinement with the lenses and light of the lantern.- As soon as the hand '30 reaches the contactpoint 33 the circuit B is again complete and thelight 22 turned on.' Y These operations ofsuccessively extinguishing the light, shifting the slides, and relighting the light are repeated'during each minute, the picture being exhibited during th at portion of the *minute 1 pointy 33 to the contact-point 31.
  • the duration of the contact between the hand 3 0' and the contact points need only be ⁇ instantaneous, and said contact-points may there- .I
  • circuits E and F are then simultaneously completed, and the solenoids 35and 24 simultaneously open-it-he ⁇ switches 34 and 23, respectively, cutting oit all oi' the operatingcircuits' except the circuits E and F, which are cut olf as soon as the hand passes oif of the button 29. Unless the setting of the contact-button 28 is changed before the hourhand 27 again arrives at eight oclock the dezice would again commence operating at that 1our.
  • the switch 4l controls all of the batterycircuits, and if said switch is opened the device Will not operate until the switch is again closed. y y
  • a lantern of the class described having a space for lantern-slides infalinement with its lenses, a sup ortingframe, a member movably mountedp in said frame and having thereon a series of slideframes l g substantially in the same plane andy eac adapted to hold a lantern-slide, means for intermittently moving said member to bring said slide-frames successivel into said s ace, means for adjusting each of said sli es laterally of its plane and independently of the other slides, said slide- 'frames' being arranged to permit slides to be removed and replaced therein Without adecting the setting of said adjusting means.

Description

PATBNTED APR. 10, 1906.
y M.'H. KILLEN. AUToMATIo `sTrmzOPTIooN APPARATUS.
APPLIoATIN FIL BD A1126. 1905.
` v I Jay PATBNTED APR. 10, 1906.
-M. H. KILLBN. AUTOMATIC STBREOPTICON APPARATUS.
APPLICATION FILED APB.. 26. 1905.
2 SHBETB-SHEET 2.
UNITED STATES PATENT oEEioE,
.MARCUS H. KILLEN, OF CHICAGO, ILLINOIS, ASSIGNOR OF ONE-HALFT yMARK L. KILLEN.
`l'AUTOMATIC STEREPTICON APPARATUS. l
Specification of Letters Patent.
VIatented. .April 10, 1906.
Application mea April 2e, i905. seria; No. 257,525.
,To dll rvwhom it may concern:
` f .Bea known ,that i, uARCUS H. KILLEN, a
- .resident of Chicago, in the county of CookV citizen ofthe United States of America, and a and State of Illinois, have invented certain new- Aand vuseful Improvements in4 Automatic f Stereopticon Apparatus, of which the following is a specification.
his invention relates to ma ic lanterns and stereopticon apparatus, and as particular reference to mechanisms for automatically c `ntrollingthe operation of a device of `this class so that all of the various mani ulaf'matically starting the device and causing the saine to operate automatically to present a series of pictures and `finally to automatically cease to operate after the expiration of a certain predetermined period of time, to provide improvedelectrically-controlled mechanisms for accomplishing the foregoing 'obiects, to rovide an improved form of slideholding evice whereby each slide of a series may be independently focused and whereby other slides may be readily substituted kfor slides already focused without disturbing the focusing adjustment, and. tov rovide in an electrically-controlled device o this class 1mproved means whereby each circiut 1s autoy matically broken when its current is not longer required, thereby preventing unnecesthe sa ve of more clcarl sary expenditurev of power. I accomplish these objects bythedevice shown in the accompanying drawings, in which- Figure 1 is an elevation, partly diagrammatic, of a stereopticon apparatus construct- ,ed according-to my invention, the casing andy some artsof the lantern lbeing omitted for showin the working parts.` Fig. 2 is a orizonta section of the same on the line 2 2 ofv Fig. y1 with some'of the spokes oi the slide-holding member omitted tor clearnessL Fi 3 is a detail of the K y'slide-holder, the arm-o the supporting inember being partly broken away. VFig. 41s an fend view of the same.
in hoders'lying in the sameplane with each' other and spaced at equal angular intervals, s ring mechanism normally urging the rotation of said member, mechanism for intermittently stpiping such rotation to successively bring i erent slides into ositions of alinement with the lenses of t e lantern, time-controlling mechanism for controlling the successive movements of the slide-holding member and for extinguishing the light of the lantern during periods in which the change of slides is taking place, and mechanism for starting the device at a certain hour of the day and stopping the operation of the same after the expiration oi' a certain predetermined interval of time.
In the construction shown in the drawings the plate-holding member 5 is in thefor'm of a wheel mounted on a horizontally-disposed shaft 6, which is journalecl in adjustable bearings 7 in the supporting-fr? me 8. The member 5 has a series of equally-spaced plateholders 9 secured to its periphery. The plate-holders 9 lie in the same plane with each other and are arranged to pass edgewise through the slide-space 10 of a lantern 11, mounted at one side of the supporting-frame.
The member 5 is provided with spring mechanism adapted to normally urge its rotation, said mechanism being indicated by the pinion 12, the gear 13, and the coiled spring 14. The rotation of the member 5 is controlled by an escapement device which consists of an electromagnet 15, having an armature 16, mountedto move intoand out of the path of the slide-frame. The armature 16 is normally urged into position for engaging the advancing edge of one ci the .frames 9, as is seen in Fig. .1.
a hollow channel-sha ed frame fitting the slide 18 and; open on t e end which' is radi.- ally outward .to permit the plates to be readily slid into or withdrawn from the. frame. The plate is retained within the frame by spring-clips 19 and bears on the'face pppo- IOCY site said clips upon a loose frame 20. The
frame 2O is adjustable against the pressure of the clips 19 by means of four adjustingscrews 21 at its respective corners. The frame 20 serves to prevent direct contact between the set-screws 21 and the glass of the lanternslide, and thus prevents unequal strain upon theglass and consequent tendency to break. The function of the screws 21 is to permit of certain ladjustment of the slide to bring it into exact focus with the lenses of the lantern.
The light of the lantern is an incandescent electric light 22 and receives its energy from circuit is controlled by a knife-switch 23, which is respectively opened and closed by The operation of the various mechanisms 2.o which have been described is controlled by Y means of a time mechanism, which is indicated by the clock-dial 26 in Fig. 1. This clock is provided with an hour-hand 27, .which is adapted to have electrical contact with two contact-buttons'28 and 29, which are otherwise insulated from the clock, but are adjustable around the dial, so as to be engaged bythe hand 27 when such hand arrives at a desired position on the dial. The buttgns 28 and 29 are adjusted to different positions by inserting their shanksin the small apertures surrounding the dial. The clock is also provided with a seconds-hand 30, l which makesv a conplete revolution every 3 5 minute and which at certain intervals of each revolution successively cornes into electrical contact with buttons 31, r32, and 33.
The various electrical circuits are indicated inthe drawings by letters ofthe alphabet, the conductors of each 'circuit being indicated by the same letter throughout. Where condue-tors are marked with a plurality of letters, such conductors form a part of each of the circuits indicated by either of such letters.
The circuit L supplies current for the light 22 of the lantern and is otherwise independentof the controllingcircuits.- The circuit L is controlled bythe knife-switch 23. The circuits A, B, C, and F are controlled by means of a switch 34, which is opened by the solenoid and closed by the solenoid 36. All of the circuits A, B, C, D, E, and F receive current from a battery 37. The conductor 38 connects directly with the clockcasing, which is in electrical circuit with the remaining parts of the time mechanism of the lclock and forms a part of 'each of the controlling-circuits.- The contact-buttons 28, 6o 29, 31, 32, and 33 are all-insulatedrom the i clockwork mechanisn l and have electrical communication therewith only when the respective hand is in contact therewith.
. The circuit D, which controls the solenoid 36, is in circuit with the contact-hutten 2g an electric circuit, (indicated at L.) This' 'point 29 1s also adjusted to the time at which Iwound and set and allowed to run, the
`tation of the seconds-hand 30 the circuits A,
-cuit C and causing the magnet 15 to lift the in which the hand 30v passes from contactand controls the closing of the switch 34 for starting the various operations of the apparatus, as will be hereinafter described. Similarly, the circuit E oplerates the solenoid 35 Jfor opening the sWitc 34 when the hand 27 7o is in contact with the button 29. The circuit F controls the solenoid 24 and opens the knife-switch 23 for cutting out the light 22 when the and 27 is in contact with the button 29. he circuit A is closed when the seconds-hand 30 is in contact with the button 31 and operates the solenoid 24 vfor extinguishing the light. The circuit C controls the magnet 15 and operates thearmature 16 of the escapement-pawl 39. The circuit B 8o when closed by the seconds-hand 30 turns on the light 22.
TheV operation of the device shown 1s as follows: A lantern-slide is inserted into each of the frames when said frame is in the position 8 5 9 at the right of Fig. 1. The slide is inserted in an upright position and will therefore Be inverted when itcomes into alin'ement with the lenses of the lantern, as is ,usual in d evices of this class. The operator then shifts 9o the button 28 to a position on the periphery of the dial of the clock to correspond to the time at'which it is desired to have the display of ictures commence'. The contactthe exhibition -isito cease'. The clock is then switches 34 and 23 being opened. When the hour-hand 27 arrives at the contact-button 28, shown at eight oclock in the drawing, then the circuit D is complete and the solenoid 36 closes the switch 34, thus connecting the batn tery with the circuits A, B, C, and F. When, the seconds-hand 30 now arrives at the con-"Q1, tact-point 33, the circuit B is closed and the solenoid 25 closes the switch 23 and turns on the light 22 in the'lantern. During each roroc C, and B will be successively closed through contact of the hand 30 with the buttons 31, 32, and 33. When the circuit A is closed, then the solenoid 24 opens the switch 23 and cuts out the light. The hand 30 next arrives at the contact-point 32, completing the cirpawl 39 lfor an instant to permit the spring to bring the next succeeding slide intov alinement with the lenses and light of the lantern.- As soon as the hand '30 reaches the contactpoint 33 the circuit B is again complete and thelight 22 turned on.' Y These operations ofsuccessively extinguishing the light, shifting the slides, and relighting the light are repeated'during each minute, the picture being exhibited during th at portion of the *minute 1 pointy 33 to the contact-point 31. The duration of the contact between the hand 3 0' and the contact points need only be` instantaneous, and said contact-points may there- .I
.Will be seen that the'w'heel 5 rotates intermittently and the pictures are successively exhibited, the-,series bei-ng repeated. Whenever f. the Wheel 5 has made a complete revolution. The devicecontinues .to loperate until the` 'hand 27" reaches `thecontact-point 29. The,y
circuits E and F are then simultaneously completed, and the solenoids 35and 24 simultaneously open-it-he `switches 34 and 23, respectively, cutting oit all oi' the operatingcircuits' except the circuits E and F, which are cut olf as soon as the hand passes oif of the button 29. Unless the setting of the contact-button 28 is changed before the hourhand 27 again arrives at eight oclock the dezice would again commence operating at that 1our.
The switch 4l controls all of the batterycircuits, and if said switch is opened the device Will not operate until the switch is again closed. y y
It will be seen that numerous details ofthe construction shown ma be altered without de arting from the spirit of my invention.
at l claim as my invention, and desire to secure by Letters Patent, is*- 1. The combination of a lantern of the class described having a space for lantern-slides in alinement with its lenses, a supporting-frame, a memberl movably mounted in said frame and having thereon a sexies of slide-frames lying substantiallyin the same plane and each adapted to hold a lantern-slide, means for intermittently moving said member to bring said slide-frames successively into said space, and means for adjusting each of said slides laterall of its plane and independently of the other s 'des 2. The combination of a lantern of the class described having a space for lantern-slides infalinement with its lenses, a sup ortingframe, a member movably mountedp in said frame and having thereon a series of slideframes l g substantially in the same plane andy eac adapted to hold a lantern-slide, means for intermittently moving said member to bring said slide-frames successivel into said s ace, means for adjusting each of said sli es laterally of its plane and independently of the other slides, said slide- 'frames' being arranged to permit slides to be removed and replaced therein Without adecting the setting of said adjusting means.
l3. In a deines of the class described, the combination of a rectangular frame having its side and end hars grooved for loosely holding a glass late, springclips adapted to bear'on one ace of said plate near its edges for clamping they plate in position, and a setscrew near each corner of the plate on the side opposite said clips and adapted for adjusting the plate laterally of the plane of said frame, all 'arranged to permit said plate to be readily removedand replaced inthe frame Without affecting the setting of said screws. zy.
4. The combination of a lantern of the class setkdescribed,l haringlenses, airspace fcrlantemslides, l 'meet f We@ sash.. ether@ mwbeahanes theme11@ .se
and alle ett-rit whtgi tptcaralna yh startle slides, meansurving Athe shiftingofsaid niembery to ymove said slidesin succession through said s ace, an'electrom'agnet escapemen't device or intermittently stopping the movement of said member to successively bring each slide to rest in said space a light-circuit, a switch controlling said light-circuit, electromagnetic means for opening and closing said switch; and clockwork mechanism for timing the operation of said means and escapement device whereby said member will be shifted at predetermined intervals and whereby said light will be exposed While said member is at rest and cut off While said member is in motion.
5. The combination of alantern of the class described havin lenses, a space for lanternslides, and an eectric light in optical alinement Witheach other; a slidesupporting member having thereon a series of lanternslides, means urging the shifting of said member to move said slides in succession through said s ace, an electromagnet escapement dlevice or intermittently stopping the movement of said member tosuccessively bring each slide to rest in said s ace; a light-circuit, a switch controlling said) light-circuit, electromagnetic means for opening and closing said switch; individual circuits controllinfr the opening of said switch, the operation oli said escapement device, the closing of said switch; and clockwork mechanism for successively closing and breaking said circuits to shift said member at predetermined intervals of time and respectively cut off and expose said light before and after the shifting ol said member.
6. The combination of a lantern of the class described havin@ lenses, a space for lanternslides, and an e ectric light in optical alinement with each other; a vslide-supporting member having thereon a series of lanterna slides, means urging the shifting of said mumber to move sai slides in'succession through said s ace, an electromagnet escapement-device or intermittently stopping 'the movement of said member to successively bring each slide to rest in said space; a light-circuit, a switch controlling said light-circuit, electromagnetic means for opening and closing said switch; individual circuits controlling the opening of said switch, the operation olA said escapement device, the closing oi said switch; a second switch for breaking said individual circuits, electromagnetic means having separate circuits for opening and closing said second switch; and clockwork mechanism haxring contact devices connected with said circuits and arranged to close seid second switch, then Si 1 successlvely cut 0E the light,' operate the escapement device, turn on the light, and to repeat such successive operations ,at intervals during a certain predetermined period of time, and then to open both of said switches.
and Y Signed at Chicago 'this 21st dey of April, 1905. v
MARCUS KILLEN. Witnesses: Y i' E. A. RUMi/,ILERI GLEN C. STEPHENS.
US25752505A 1905-04-26 1905-04-26 Automatic stereopticon apparatus. Expired - Lifetime US817251A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US25752505A US817251A (en) 1905-04-26 1905-04-26 Automatic stereopticon apparatus.

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US25752505A US817251A (en) 1905-04-26 1905-04-26 Automatic stereopticon apparatus.

Publications (1)

Publication Number Publication Date
US817251A true US817251A (en) 1906-04-10

Family

ID=2885732

Family Applications (1)

Application Number Title Priority Date Filing Date
US25752505A Expired - Lifetime US817251A (en) 1905-04-26 1905-04-26 Automatic stereopticon apparatus.

Country Status (1)

Country Link
US (1) US817251A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2713739A (en) * 1951-05-21 1955-07-26 Rowe Mfg Co Inc Display device for merchandising machines
US3210487A (en) * 1960-11-07 1965-10-05 Holzer Walter Apparatus comprising a timing mechanism and an intermittent switching mechanism

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2713739A (en) * 1951-05-21 1955-07-26 Rowe Mfg Co Inc Display device for merchandising machines
US3210487A (en) * 1960-11-07 1965-10-05 Holzer Walter Apparatus comprising a timing mechanism and an intermittent switching mechanism

Similar Documents

Publication Publication Date Title
US2421986A (en) Alarm clock and switch
US4079400A (en) Optical blade drive apparatus
US817251A (en) Automatic stereopticon apparatus.
US2782274A (en) Low cost clock switch
US2559910A (en) Electric timer
US2489098A (en) Process timer
US2393408A (en) Electrically controlled iris diaphragm
US2080330A (en) Electric program clock
US3526455A (en) Tachistoscopic apparatus
US670634A (en) Electric clock.
US2058609A (en) Electric clock mechanism
US3620004A (en) Time indicating device of direct read-off type
US1233692A (en) Time-switch.
US1565334A (en) Electric clock-setting means
US2002421A (en) Electric timepiece
US746708A (en) Electric time-switch.
US1413075A (en) Distbict of coi
US1060630A (en) Electric time-switch.
US703033A (en) Electric time-switch.
US1935982A (en) Coin control mechanism for electrically operated machines
US2148790A (en) Time controlled electrical switch
US1484041A (en) Electric clock-setting means
US611822A (en) schmidt
US513469A (en) gerry
US2354511A (en) Time system