US1937883A - Time recorder - Google Patents

Description

1933- c. M. F. FRIDEN El AL 1,937,383

TIME RECORDER Filed June 9, 1931 3 Sheets-Sheet 1 FIEL Dec. 5, 1933. c. M. F. FRIDEN ET AL TIME RECORDER 3 Sheets-Sheet 2 Filed June 9, 1931 NHyN mFn m mfam H mm Z Dec. 5, 1933. Q FR|DEN ET AL 1,937,883

TIME RECORDER Filed June 9, 1951 3 Sheets-Sheet 3 A TTORNEYS.

Patented Dec. 5, 1933 UNITED STATES 1,937,889 TIME RECORDER Carl M. F. Friden, Piedmont, and John Renholts, Oakland, Galit, assignors to Instograph, Ltd., Oakland, Calif., a corporation of California Application June 9, 1931. Serial No. 543,078

16 Claims. 01. 185-40) This invention relates to time recorders and the like and is particularly applicable to recorders which are electrically operated. In the copending application Serial Number 399,232, filed October 12, 1929 by Carl M. F. Friden, a time recorder is disclosed inwhich the timing unit is adapted to be driven by a commercial source of regulated alternating current.

It is one object of the present invention to provide a time recorder having timing means which is operable from a source of regulated or unregulated alternating current or from a source of direct current. i

Another object is to provide a timing unit in apparatus of the class described in which energy storing neans :is provided for driving the timing unit for a definite time interval and having means for automatically reconditioning the energy storing means at the termination of said time interval.

Another object is to provide a timing unit of the character described which is instantaneously energized at regular intervals and which is unaffected in accuracy by fluctuations or failure of the energizing current when such irregularities occur within the time interval between successive energizations.

Still another object is to provide a time records er of the character described having a novel time controlled switch for accurately controlling the energization of the timing unit.

Still another object is to provide a time recorder of the character described which is reliable and accurate in operation.

These and other objects and advantages are attained in the embodiment of my invention illustrated in the accompanying drawings, in

which: i

Fig. l is a side elevation of a time recorder embodying the principles of this invention, the casing of the recorder being broken away to show the internal construction and certain parts of the device being shown in cross section.

Fig. 2 is a side elevation of the recorder shown in Fig. 1 illustrating the internal construction thereof, as viewed from the opposite direction.

Fig. 3 is a detailed view of the timing unit showing the novel time controlled switch of this invention mounted thereon.

Fig. 4 is a cross sectional view taken on the plane indicated by line 44 of Fig. 3.

Figs. 5, 6 and 7 arecross sectional views taken on planes indicated by section lines 5-5, 6-6 and 7-'7, respectively, of Fig. 4 showing certain constructional features of the timing unit.

Fig, 8 is a detailed view of a biasing spring employed in the time controlled switch of the recorder.

In its preferred form the time recorder of our invention comprises time printing apparatus which is set by a suitable timing unit. The tim ing unit of the present invention preferably comprises a clock mechanism which is driven for definite recurring time intervals by suitable 6,121 ergy storing means, such as a spring, the energy storing means being automatically reconditioned at the end of each time interval by an electrical impulse to drive the clock mechanism for the next time interval, and so on, the clock mechanism being operated indefinitely as long as elecs trical impulses are imparted at the end of each time interval to the means provided for reconditioning the energy storing means. Electromagnetic means is preferably employed for reconditioning the energy storing means and a time controlled switch actuated by the timing unit controls the energization of the electromagnetic means. The time interval selected for reconditioning the energy storing means can be of any desired durationand it is not essential from the view point of accuracy that this time interval be a standard unit of time. We have found that an interval of approximately ne minute duration gives satisfactory results, but if desired, any suitable fractional part of a minute or multiple 5 of a minute can be chosen as the time interval.

The time between successive. actuations of the switch should be relatively consistent and it is also desirable that'the timerequired for actuation of theswitch be as constant as possible so that accurate compensation can be made in the tim ing unit for correcting any error which may be due to the switch actuation. In the embodiment of our invention illustrated in the accompanying drawings, both the period between successive actuations of the switch and the period required for each switch actuation areaccurately, con.- trolled, therebyeliminating all errors attributable to these factors. 4

Referring now to the drawings, we have shown a time recorder somewhat similar in general op.- eration to that disclosed in the Friden application hereinabove reierred to and the common ieatures will be described herein only briefly, reference being had to the prior application for a morefdetailed description. As illustrated inthe draws ings, the operating parts of the recorder are en: closed in a suitable casing 16 which is provided with a slot 1'7 for the insertion of a sheet of paper or the like on which the time is to be recorded.

One or more guiding arms 18 can be provided for directing the sheet into the path of a pair of contacts 19 and 21. Contact 19 is relatively movable and is adapted to be caused to engage the contact 21 by the force of the paper against the same.

Contacts 19 and 21 are adapted to control the energization of a solenoid 22 having a movable core 23 which strikes a plunger 24 when the solenoid is energized. The plunger 24 carries at its upper end a printing platen 26 and the force of the impact against the plunger 24 causes the platen to effect a printing stroke by lifting the inserted sheet and pressing the same against the printing surfaces of one or more type wheels disposed adjacent the upper portion of the slot 17. When the inserted sheet is raised in this manner it releases the contact 19 thereby permitting it to its normal position to deenergize the solenoid 22. One of the printing wheels is illustrated diagrammatically at 27 and a ratchet wheel 28 is adapted to be actuated step-by-step at regulated intervals to effect the setting of the printing wheels in a manner described in the aforementioned Friden application. An ink ribbon, not shown, is automatically fed by pawl mechanism indicated generally at 29 acting upon ratchet wheels 31 and 32 and controlled by a linkage of levers, of which 33 is one, set in inotion each time the solenoid 22 is energized, as described in said Friden application.

The present application is more particularly concerned with a novel timing unit illustrated generally at 34 in Figs. 1 and 2 and shown in detail in Figs. 3 to 8, inclusive. The timing unit comprises a clock mechanism 36 driven for definite recurrent time intervals by energy storing means, such as a spring 37, reconditioned at the end of each time interval by electromagnetic means 38. The energization of the electromagnet 38 is controlled by a time controlled switch having a pair of contacts 39 and 41.

Contacts 39 and 41 are connected byleads 42 and 43 in a simple series circuit, or otherwise,

with the electromagnet 38' and a source of operating current, which for the present purposes can be either direct current or regulated or unregulated alternating current, so that engagement of the contacts 39 and 41 causes energization of the electromagnet 38. Electromagnet 38 is provided with an armature 44, pivoted about a pivot 45, about which it is adapted to rock in a counter-clockwise direction, as viewed in Fig. 2, when the electromagnet 38 is energized. An extension 46 of the armature 44 is pivotally connected at its upper end to an arm 47 provided with a pawl 48 at its other end which engages the teeth on the ratchet wheel 28 of the printing'mechanism. Thus, in the embodiment illustrated, ratchet wheel 28 is adapted to be moved step-by-step in accordance with the energization of the eleotromagnet 38 and thereby advance or set the printing wheels to impart the desired information. Suitable means, such as a spring 49, can be provided for biasing the pawl 48 into operative engagement with the teeth on the ratchet wheel 28.

Mounted on the pawl arm 47 is an extension 51 carrying a rod or pin 52 which passes slidably through an aperture in the one end of a lever 53 pivoted for rocking movement about the shaft 54 of a ratchet wheel 56. Movement of the pawl arm 4'7 to the left, as viewed in Fig. 2, effected by energization of the electromagnet 38, effects rocking movement of the lever 53 in a counterclockwise direction through the intermedium of the rod 52. If desired, yieldable means, such as a spring 55, can be interposed between the end 57 of the rod 52 and the lever 53 to make the force acting on lever 53 yieldable in nature. A spring pressed pawl 58 is pivotally mounted on one end of the lever 53 and is adapted to engage the teeth of the ratchet wheel 56. The other end 59 of the lever 53 is connected to one end of the spring 37 which is employed to drive the clock mechanism of the timing unit. Upon rocking movement of the lever 53 in the manner heretofore described, the pawl 58 engages a succeeding tooth on the ratchet wheel 56 and the driving spring 37 is simultaneously tensioned. When the electromagnet 38 is deenergized the force of the spring 37 is directed through the lever 53 for imparting rotational movement of the ratchet wheel 56. Rigidly secured to the shaft 54 of the ratchet wheel 56 and mounted to rotate therewith is a gear 61 which constitutes one of the gears of the clockwork mechanism 36. An escapement mechanism, shown generally at 62 and illustrated in detail in Fig. '7, can be employed to regulate the rate of movement of the clockwork mechanism 36. The escapem-ent mechanism 62 is not unlike the type commonly employed in watches and other time keeping devices. Since the ratchet wheel 56 is directly connected with the clockwork mechanism 36 the rate at which the ratchet wheel is permitted to rotate and consequently the rate at which the energy in spring 3'7 is expended, is controlled by the clockwork mechanism 36. II" the rate of movement is regulated in such a manner that the time required for the ratchet wheel 56 to rotate a distance corresponding to one tooth is equivalent to a time interval .of approximately one minute, then each time the lever 53 is actuated to engage a successive tooth sufficient energy will be stored in the driving spring 37 to drive the clock mechanism for a corresponding time interval.

In the embodimentof our invention illustrated, the contacts 39 and 41 are parts of a time controlled switch which is adapted to be closed at the termination of each of the selected time intervals to energize the electromagnet 38 and thereby effect the tensioning of the driving spring 37. Thus, we have shown the contacts 39 and 41 as being secured on arms 63 and 64 which are mounted for pivotal movement about pivots 66 and 67, respectively. A pin 68 mounted on lever 53 passes through a slot 69 in arm 63 so that movement of the lever 53 in either direction eiiects a corresponding movement of the arm 63 about its pivot 66. Accordingly, when the lever 53 is moving relatively slowly in a clockwise direction under the force of spring 37 and at a rate which is determined by the clock mechanism 36 and ratchet wheel 56, the contact arm 63 follows at a correspondingly slow rate and is moved toward the contact arm 64.

A biasing spring 71, preferably in the form of a loop, is fixed to the end of the arm 64 and has its looped end contacting against the upper edge of the contact arm. 63. The upper edge or" arm 63 against which the biasing spring '71 bears is a cam surface and is shaped as shown, having a portion 72 extending approximately perpendicularly from one of the longitudinal edges of the contact arm and a bevelled portion "13 which makes an obtuse angle with both the end portion 72 and the other longitudinal edge of the contact arm. The looped end of the biasing spring '71 is adapted to bear against the bevelled perill succeeding tooth ontheratchet wheel 56.

tion' 73 when the contacts39' and 41 are in em gagement and is adapted to bear against the perpendicular end portion '72 when the contacts are separated. The force of the spring 71 is directed downwardly against the end of the con theforce-of the spring tends tokeep the contacts in engagement. Thus, when the parts are in the position shown in Fig. 3 with the contacts 39 and 41 in engagement, the force of the spring '71is directed downwardly and in a direction approximately parallel with the longitudinal center line of the contact arm 63. The bevelled end portion '73 against which the spring bears acts as a cam surface under these conditions and as the end of the spring moves ortends to move along the portion '73, the contact 41 is caused to move into engagement with the contact 39.

When the contacts 39 and 41 are brought into engagement, the electromagnet 38 becomes energized and effects a rocking movement of the lever 53 in a counter-clockwise direction and the pin 68 moves therewith to the left, carrying with it the contact arm 63. The contact arms 63 and 64, being interconnected by the spring '71, both rock together about their respective pivots 66 and 6'7. During this movement the contacts 39 and 41 remain in engagement but there is a beneficial relative sliding movement between the contacts on account of the contact arms 63 and 64 being mounted on spaced pivots. This sliding action between the contacts 39 and 41 effects wiping of the surfaces thereof, thereby insuring a clean and firm contact. A stop member '74 projects into the path of the contact arm 64 and when the arm64 strikes this stop, further movement of the contact arm 63 causes the spring '71 to slide along the bevelled end portion '73 towardthe perpendicular end portion '72. Im-

mediately upon the spring "71 passing the intersection between the portions '72 and '73, the force component of the spring acting between the arms 63 and 64 becomes such as to force the arms violently away from each other, the arm '64 being forced against a back stop '76.

Energization of the electromagnet 38in this manner tensions the spring 3'7 and when the electromagnet is .deenergized upon opening of the switch, the force of the spring 37 tends immediately torestorethe lever 53 and with it the lever 63 to the position shown in Fig. 3. 1 Such movement, however; isde1ayed"by the pawl 58 on the lever 53 which becomes engaged with a The spring 3'7, thereforamust move the ratchet wheel 56 a distance corresponding to one tooth thereon before the switch contactst39 and 41 will be restored to their engaging position. The rate at which the ratchetwheel 56 is permitted to rotate underthe influence of spring 37 is accurately regulated by theclock mechanism 36. and the escapement mechanism 62, and assuming that this rate is such that the ratchet wheel 56 moves a distance of one tooth in a time interval of approximately one minute, for example, the contact 39 on arm 63 will be moved gradually to the contacting position in the same time interval. During this movement of the contact 39, the biasing spring 71 rests against the perpendicular end '72of the arm 63 and the force component acting between the arms 63 and 64 is such as to bias the same away from each other, the arm 64 being forcibly held against the stop '76. As the arm 63 moves toward the arm 64 the perpendiculai' end 72 of arm 63 slides against the looped end of spring '71 and just as the contact 39 is moved into contacting position, the bevelled end '73 of the arm 63 is moved adjacent the end of the spring '71. The point of application of the spring '71 thereby changes and immediately the force component acting between the contact arms 63 and 64 becomes such as to tend to draw the arms together. Arm 63 is constrained to move slowly, but the arm 64, being free to move about the pivot 6'7, is violently drawn toward the arm 63 thereby rapidly bringing the switch contacts 39 and41 into engagement, as shown in Fig. 3. By this movement the contact arm 64 is caused to leave its position of rest against the stop '76, as illustrated. Upon closing of the switch the electromagnet 38 is energized to effect movement of the lever 53 so that the pawl 58 thereon engages the succeeding tooth of the ratchet wheel 56 and the driving spring 3'7 is retensioned simultaneously. Also, the pawl 48 moves the ratchet wheel 28 to eifect the setting and break of the switch contacts, the time required for each operation of the switch can be accurately determined and can be readily compensated for in adjusting the timing unit, thereby insuring a high degree of accuracy in the setting of the time mechanism.

Summarizing the operation of the recorder, the printing stroke is effected upon insertion of a sheet of paper or the like into the slot 1'7. The information recorded on the paper is determined by the setting of the printing wheels, of which 27 is one, and the setting of the printing wheels is controlled by the electromagnet 38, which upon each energization effects movement of the ratchet wheel 28 one step. The energization of the electromagnet 38 is controlled by the time controlled switch having the contacts 39 and 41 and this switch is adapted to be closed at the end of recurrent predetermined time intervals. The length of each time interval is determined by the timing unit which effects movement of the contact 39 toward the contact 41 at a relatively slow rate. During this movement of the contact 39, the force component of the biasing spring '71 is such asto force the contacts 39 and 41 away from each other, but upon reaching the position of contact, the force component of the spring acting between the contacts changes by reason of the change in the point of application of the spring on the arm 63, so that the contact 41 is violently drawn toward the slowly moving contact 39, thereby insuring rapid closing of the switch. The electromagnet 38 is thereupon energized and attracts its armature 44, thereby efiecting actuation of the'ratchet wheel 28 of the printing mechanism and simultaneously tensioning the driving spring 3'7 of the timing unit. The electrical im pulse flowing through electromagnet 38 is only of momentary duration since the circuit is broken as soon as its armature 44 has been moved a sufficient distance to effect separation of the contacts 39 and 41 through the arms 46- and 47 and the lever 53. Separation of the contacts 39 and- 41 is effected by moving both contact carrying arms 63 and 64' toward the left, as viewed in Fig. 3, until the arm 64' strikes the stop '74, Continued movement of the arm 63, caused mainly by the momentum of the various interconnected parts causes the spring 71 to disengage the bevelled portion 73 of the arm 63 and to engage the perpendicular end portion '72 thereof. The force component acting between the arms 63 and 64 of the spring 71 then becomes such as to force the contacts 39 and 41 away from each other and contact ii is quickly forced against its back stop '76.

The energy stored up in the driving spring 37 drives the clock mechanism 36 of the timing unit until the contacts 39 and 41 again make engage- I ment and the cycle is then repeated. It will be noticed that the rate at which the clock mechanism is driven in the interva between electrical impulses is independent of the source of electrical energy and irregularities or even complete failure of the source during the period will have no adverse affect on the accuracy of the timing unit. So long as the impulse applied to the electromagnet is of sufficient magnitude to effect attraction of the armature 44, it is immaterial whether the source delivers regulated or unregulated alternating current or constant or pulsating direct current. The biasing arrangement afforded by the spring 71 insures quick make and break of the contacts 39 and 41 and the feature of biasing the contacts away from each other until the switch is about to be closed and biasing the contacts toward each other until the switch is about to be opened insures positive action ofthe switch at all times. All of these features of the time controlled switch contribute toward making the recorder accurate, inasmuch as the time consumed for actuation of the switch remains constant and accordingly accurate compensation can be provided therefor.

While we have shown and described a preferred embodiment of our invention, it is to beunderstood that we do not wish to be limited thereto, since the invention as defined in the appended claims can be embodied in a plurality of other forms.

We claim:

1. In a time recorder, a time controlled switch having a pair of movable contact members, resilient means effective only through said contact members for biasing said contact members away from each other, and time controlled means for shifting at least one of the points of application of said resilient means to effect biasing of said contact members toward each other.

2. In a time recorder, atime controlled switch having a pair of movable contact members, a single spring mounted on one of said movable members for biasing said contact members away from each other for a predetermined time interval and for urging said contact members together at the end of said time interval.

3. In a time recorder, a time controlled electric switch having a pair of movable contact members, resilient means entirely supported by said contact members for biasing said contact members away from each other for a predetermined time interval to maintain said switch open and for urging said contact members together at the end of said time interval to effect rapid closing of said switch.

4. In a time recorder, a time controlled elecfrom each other for a predetermined time interval to maintain said switch open and time controlled means operative at the end of said time interval to shift at least one of the points of application of said spring to effect biasing of said contact members toward each other.

. 5. In a time recorder, a base, an electric switch having a pair of contact arms movably mounted on said base, asingl'e spring entirely supported by said contact arms for biasing said contacts away from each other for a predetermined time interval and means operative at the end of said time interval for causing said spring to urge said contacts together. I

6. In a time recorder, a time controlled switch having a pair of movable contacts, means for moving one of said contacts toward the other at a definite rate and means for rapidly moving the other of said contacts to close the switch when the distance separating the contacts falls to a predetermined value.

7. In a time recorder, a time controlled switch, said switch having a pair of contacts each mounted on a pivoted arm, means for moving'one of said arms toward the other at a definite rate and biasing means for moving the other arm to effect rapid closing of the contactswhen the distance between the contacts reaches a predetermined value.

8. In a time recorder, a time controlled switch having a pair of movable contacts, means for moving one of said contacts relatively slowly and means for moving the other of said contacts relatively rapidly to effect closing of the switch.

9. In a time recorder, a time controlled switch having a pair of movable contacts, means for moving one of said contacts relatively slowly and means operative after a predetermined amount of movement of said slowly moving contact for movingthe other contact relatively rapidly to effect closing of the switch.

10. In a time recorder, a time controlled switch having a pair of contacts, means for moving one of said contacts relatively slowly and a spring acting between said contacts for moving the other of said contacts relatively rapidly after a predetermined amount of movement of said slowly moving contact to effect closing of the switch.

11. In a time recorder, a time controlled switch having a pair of movable contacts, means for moving one of said contacts relatively slowly and means for'moving the other of said contacts relatively rapidly after a predetermined amount of movement of said slowly moving contact to effect closing of the switch, means operative upon the closing of the switch to effect movement of both switch contacts in the same direction and at the same rate, and means operative after a predetermined amount of movement in said direction to effect separation of said contacts.

12. In a time recorder, a time controlled switch having a pair of contacts, means for moving one of said contacts relatively slowly and a spring for moving the other of said contacts relatively rapidly after a predetermined amount of movement of said slowly moving contact to effect closbers for mutually biasing said contact members.

14. In a time recorder, a base, a contact member movably mounted on said base, and a spring bodily movable with respect to said base for biasing'said contact member.

15. In a time recorder, a base, a first contact member movably mounted on said base and having a cam surface, a second contact member movabiy mounted on said base, and a spring mounted on said second member and adapted to abut said cam surface.

16. In a time recorder, a base, a pair of contact members mounted on said base to pivot about difierent centers, and a spring mounted on one of said contact members and abutting the other of said contact members to bias said contact members together in one relative position thereof and to bias said contact members apart in another relative position thereof.

CARL M. F. FRIDEN.

JOHN RENHOLTS.

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