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Publication numberUS2433398 A
Publication typeGrant
Publication dateDec 30, 1947
Filing dateSep 1, 1945
Priority dateSep 1, 1945
Publication numberUS 2433398 A, US 2433398A, US-A-2433398, US2433398 A, US2433398A
InventorsRichard Charles D
Original AssigneeBell Telephone Labor Inc
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Indicating keyboard telephone call transmitter
US 2433398 A
Images(4)
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Description  (OCR text may contain errors)

Dec. 30, 1947. c, RICHARD 2,433,398

INDICATING KEYBOARD TELEPHONE CALL TRANSMITTER Filed Sept. 1, 194 5 4 Sheets-Sheet l I INVENTOR By CDR/C/MRD ATTORAEY 46 45 50 R 34 5C 2/ I 8 5/ 43 $72 32 30 22 Dec. 30, 1947. c. D. RICHARD 2,433,398

INDICATING KEYBOARD TELEPHONE CALL TRANSMITTER Filed Sept. 1, 1945 A 4 Sheets-Sheet 2 I C! 45 50 R L2 SC 30 22 INVENTOR ST 2 2 32 c. 0. RICHARD Z9. @M M ATTORNEY INDICATING KEYBOARD TELEPHONE CALL TRANSMITTER Filed Sept. 1, 1945 4 Sheets-Sheet 5 FIGS . F G. o

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lNl/ENTOR C.D.R/CHARD ATTORNEY Dec. 30,1947. v c, RICHARD. 2,433,398

INDICATING KEYBOARD TELEPHONE CALL TRANSMITTER Filed Sept. 1, 1945 -4 Sheets-Sheet 4 FIG. 7

DPEEATDE 58 KEY .54

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IN VENTOI C D R/CHA RD A TTORNE Y Patented Dec. 30, 1947 INDICATING KEYBOARD TELEPHONE CALL TRANSMITTER Charles D. assignor corporated, New York,

New York Richard, West New Brighton, N. Y., to Bell Telephone Laboratories, In-

N. Y., a corporation of Application September 1, 1945, Serial No. 613,980

Claims.

This invention relates to telephone call transmitters of the key-operated type.

The object of the present invention is the provision of a call transmitter of the type above re ferred to which will be simple in construction, convenient in use, accurate in operation, and which will indicate the sym 01 of the depressed key at each stage in the sending of a telephone call designation.

A novel feature in the telephone call transmitter of this invention is the provision of means actuated by the operation of any key in a set of symbol carrying key members for tensioning a motor spring serving to operate a gear sector forming the driving element of a speed multiplier gear mechanism, such gear mechanism actuating a pulsing mechanism and an element of a mechanism controlling the operation of the pulsing mechanism.

Another feature is the provision of means normally positioned in the path of the element in the mechanism for controlling the' operation of the pulsing mechanism for preventing the operation of the gear speed multiplier and that of the pulsing mechanism during the tensioning of the motor spring by the movement of the means actuated by the individual operation of the keys, such positioned means being actuated for permitting the operation of such element following the operation of a mechanism serving to lock the depressed key into the operated position preparatory to the operation of the pulsing mechanism.

Another feature is the provision of means movable by the operation of the means actuated by the depressed key keys in that position, such locking operation occurring in timed relation with the release of the element in the mechanism controlling the operation of the pulsing mechanism.

Another feature is the provision of a plurality of means each actuated by the operation of its respective key for locking the latter in its oper-' ated position, each of such means positioning a pivoted member carried thereby in the path of the element in the pulsing controlling mechanism for actuating such a. member and thereby causing the release of the operated key and the closing operation of a shunting contact in circuit with the contact actuated by the pulsing mechanism,

Another feature is the provision of means operated by the movement of the speed multiplier mechanism for indicating the symbol of the key depressed.

Another feature is the provision of a mechafor locking the non-operated .ing the transmitter mechanism removed nism for holding the indicating means in each indicating position against the tension of a spring serving to return the indicating means to normal position, such return movement being effected upon the operation of said holding mechanism by the operation of each succeeding key member in the writing oper tion of a telephone call designation.

Another feature is the provision of means actuated by the placing of the telephone handset into its support to cause the operation of the mechanism holding the indicating means to operated position for releasing the indicating means, as when following a telephone conversation.

Other novel features and advantages or this invention will appear from the following description and by the claims appended thereto, reference being had to the accompanying drawings in which:

Fig. 1 is an elevation of the telephone call transmitter of the invention shown in perspective;

Fig. 2 is a right side elevation view shown with a number of parts with portions broken away and the casing partly in vertical longitudinal section taken on line 2-2 of Fig. 6, the operating parts being shown in normal positions;

Fig. 3 is a view similar to that of Fig. 2 but showing one of the keys in the operated position;

Fig. 4 is a view similar to that of Figs. 2 and 3 but showing the pulsing mechanism and the digit indicating wheel in the operated position at the time when the operated key is being released by its respective locking pawl;

Fig. 5 is a top view shown with the casing housand the mechanism in normal position;

Fig. 6 is a rear elevation view shown with the casing in vertical cross-section;

Fig. 7 is a partial view shown in vertical section taken on line 'l-'I of Fig. 6, showing the digit indicating wheel and its controlling mechanism in normal positions;

Fig. 8 is a partial top view showing the release mechanism for the digit indicating wheel controlled by the placing of the telephone handset on its support;

Fig. 9 is a partial detail view of the combined step bar gear sector unt actuated by the speed gear multiplier mechanism; and

Fig. 10 is a view of a telephone coin collector embodying the call transmitter of this invention.

In the construction of the call transmitter of this invention, a base I shown in Figs. 2, 3, 4, 5 and 6 is provided for securing as by a number of similar screws a mounting plate 2 which is formed at its front end portion with two upright supports 3 serving as bearings for a shaft 4, and on this shaft is mountedfor pivotal movement a set of key members KI, K2, K3, K4, K5, K6, K7, K8, K9 and KIO held in spaced relation to each other at their pivoted ends by a notched bar itself pivoted on upright extending lugs 6 formed with the arms I of a U-shaped bar I-I pivoted on shaft 4 and actuated by the movement of any one of the keys KI, K2, K3, etc. The keys KI, K2, K3, etc., are held in normal position .as shown in Figs. 1, 2, 5 and 6 by the tension of similar reed-type retractile springs 8 while the U-bar H is held against lugs such as 9 formed with the keys KI, K2, etc., by the tension of a retractile helical spring I0,

One arm I of the U-shaped bar H is provided with a stud II laterally extending therefrom for securing the outer convolution of a spiral spring I2 best seen in Figs. 2, 5 and 6 having its inner convolution secured to .the hub portion I3 of a gear sector I4 pivoted on shaft 4. Gear sector I4 meshes with a pinion I5 mounted on a shaft I1 for rotation as a unit with .a gear I3 while the gear I6 meshes with a second gear sector I3 pivoted on shaft 4, the shaft I! being journal-ed at one end in an upright support I9 formed with the mounting plate 2 and its opposite end in an upright extending lug 20 formed with abracket 2| secured to the mounting plate 2 by a number of screws 22. v

The gear I6 meshes with a gear 23 and with a pinion 25, the gear 23 actuating a digit indicating wheel 24 in a manner which will be hereinafter described in detail While the pinion 25 is mounted for rotation as a unit with a pulsing cam 26 on a shaft 27 having one of its ends journaled in the upright support I9 and its opposite end in the upright support 28 of bracket 2|.

An angle-shaped lever member 29, best seen .in Figs. .-2, 3 and 4, is pivoted on a support 39 and upright extending lug 28 with one arm disposed in operative relation with the pulsing .cam 26 while its other arm carries a roller r0 disposed in operative relation with the operable spring 32 of a pulsing contact 3I, Fig. 6, formed in cooperation with the operable spring 32 and a stationary spring 33 mounted in a, pile-up arrange ment on a bracket 34 formed with the mounting plate 2.

The operation of contact 3I is effected by the movement of the gear sector I4, I5-I6, pinion 25 under the tension of .motor spring I2 but under the control of a centrifugal speed governor'SG driven by a Wormgear 35 which is mounted for free rotation on shaft 27 through a one-way clutch in the form .of a spring '36, coiled on the hub' of worm gear 35 and on the hub of pulsing cam 26, the clutch spring 36 being wound in a manner to permit the return of the pulsing cam and its actuating gear mechanism to normal independently of the speed governor CG. The operation of gear I6 is effective to actuate a gear sector I8 pivoted On shaft '4 while a bar 3?, best seen in Figs. 5 and 6, is formed at one end with an arm 38 pivoted on shaft '4 and the other end of this bar terminates in the 'form of a lug portion L secured as by a rivet '39 to the gear sector I8 for arcuate movement as a unit therewith as efiected'by the tension of the motor spring I2. The release of bar 31 is efiected through the engagement of a roller 4I carried by pinion gear unit one of the arms I of the U-shaped bar H with the cam portion CP2 of a pawl-shaped member 40 for disengaging the lug 4hr formed with this pawl-like member from the bar 31 upon the operation of the U-shaped bar H under control of any one of .the key members KI, K2, K3, etc.

Each key member KI, K2, K3, etc., carries a roller 43 best seen in Figs. 2, 3, 4 and 7 provided for engaging the camming surface of a respectively associated pawl 42 for moving the latter against the tension of a retractible sprin R for locking the depressed key in its operated position which occurs following the locking of the nonoperated keys K2, K3, etc., to normal by the pivotal movement of a plate PL on studs ST and ST2 for positioning its top disposed edge in the path of lugs as LS formed at the free end of the keys, such pivotal movement being effected through the engagement of the roller 4| carried by the U-shaped bar H -with the cam Portion CP formed with the plate P The operation of each pawl 42 in response to the operation of its respectively associated key is effective to position a yoke member Y pivoted thereon wherein the free end portion of arm 44 of this yoke is engaged by its corresponding step as Ice, 2m, 3x, 4x, 53:, 6:0, 111,32, 9a: and like shown in Figs. 2, 3, 4, 5, 6 and 9 forming the diagonal or staggered edge of the bar 31 the steps Im, 20:, 3.1:, etc., being of a pitch proportional to the spac ing of the cam portions or teethof pulsing cam 2.6.

The engagement of arm 44 of yoke Y by step bar 31 is effective to impart a pivotal movement to this yoke to cause its opposite arm 45 to -enage with a U-shaped bar 45, Figs. 2, 3 and 4, pivoted on shaft 4 to close a contact 41 having its operable spring 48 disposed in engageable relation With aninsulated stud 49 carried by one arm of the bar 46. The closing of contact 47 serves to establish a shunt around the telephone line followingthesending of a train of pulses correspond ing to the key depressed, while the continued movement of yoke Y by the step bar 37 is effective to engage a projection 50 formed with the yoke Y with a stop bar 5| secured to the mounting plate 2 to cause the pivotal movement of its supporting pawl 42 :from the position shown in Fig. 3 to the position shown in Fig. 4 for releasing the operated key which is returned to normal by the tension of its own retractile spring 8 while the :U-shaped bar H is returned to normal position by .its retractile spring I 0. In the return movement of U-shaped bar H, this bar engages a lug LI, best seen in Fig. 5, laterally extending from the gear sector I8 for returning the latter and consequently the .step bar :37 to normal and through the pinion gear unit i.5| 6 the gear sector I4 and theimpulse cam 26, but the speedgovernor SG because of the one-way clutch spring 36 is not operated during the return of the impulse cam to normal.

The digit of the key depressed and, therefore, the operation of pulsing cam 26 following the sending of each train of pulses is indicated by a printed dial on the indicating wheel 24 which is mounted for free rotation on a shaft 53 and actuated by an arm 54 keyed to one end of the sleeve 55 mounted for free rotation on shaft 53 as efiected by the rotation of gear 23 secured to the opposite end of sleeve 55 and meshing with gear I6 of-the gear pinionunit I.5I6 .abovementioned.

The arm 54 is disposed in engageable :relation with a projection 51 extending laterally from the indicating wheel 24 for imparting rotary movement to this wheel corresponding to that of pulsing cam 26 against the tension of a retractile spring 58 best seen in Figs. 5, 6 and 8 having one of its ends secured to a collar member 59 secured to the shaft 53 and its other end secured to a ratchet wheel 60 in turn secured to the indicating wheel 24. A ratchet pawl 6| best seen in Figs. 6, 7 and 8 is mounted for pivotal movement on a shaft 52 with a downwardly extending arm 53, the latter having a stud 54 at its free end portion for engaging with a pawl 65 pivoted to the upright extending arm 66 of pawl 40 to cause the pawl 55 to disengage the retaining pawl from the ratchet wheel 5|],so as to permit the latter to return to normal position following the operation of any one of the key members Kl, K2, K3, etc., and that of U -shaped bar H which, as above-mentioned, through the roller 4| carried thereby engages the cam portion CP2 of pawl 46. The operation of pawl 40 and, therefore, that of pawl 65 pivoted thereon from the position shown in Fig. 7 to the position shown in Fig. 4, the arm 63 has moved the pawl 5| in disengaged position from the ratchet wheel 60 where it is held a sufficient length of time prior to reaching the position shown in Fig. 4 for permitting the indicating wheel to return to position where the lug 51 carried by this wheel reengages the driving arm 54 followed by the movement of pawl 65 to the opposite side of pin 64 to the position as indicated in Fig. 4, thus causing the retaining pawl 8| to reengage the ratchet wheel 60 by the tension of a retractile spring 51 coiled on shaft 52, the pivotal movement of pawl 65 on arm 56 permitting the return of pawl 40 to normal position following the return of the U-shaped bar H to normal position at the conclusion of each digit sending operation.

On shaft 62 is keyed a pair of arms 68 and BSY which extend in engageable relation with plunger members 59 guided in similarly sized holes in the casing Cl housing the transmitter mechanisms, the arm 68Y being provided with a projection 1| for actuating the retaining pawl 6| independently of the operation of pawl at for permitting the return movement of the indicating wheel 24 to normal upon the placing of the handset 19 in position in its supporting cradle as shown in Fig. 1 for actuating the plungers 63- by gravity.

A typical example of operation is as follows: The operation of key KIO, for example, having the marking symbol Z operator 0 from the position shown in Figs. 1 and 2 to the position shown in Fig. 3 is effective to impart a pivotal movement to its associated pawl-like member 42 to cause this pawl under the tension of its retractile spring R. to engage the roller 43 carried by that key to hold the latter in the operated position where the pawl 42 and the yoke Y are held in the position wherein the free end of arm 44 of yoke Y is positioned for engagement by the step Illa: of the step bar 31 upon the operation of the latter in a manner which will be hereinafter described in detail.

The operation of the key II] also imparts a pivotal movement to the U-shaped bar H for tensioning the motor spring |2 due to the gear sector l4 being prevented from operating by the pawl 40 having its lug portion 4L1: engaging the lower disposed edge of step bar 31 as best seen in Fig. I. The operation of U-shaped bar H through the roller 4| is efiective to engage the camming portion 0P2 of pawl 40 for disengaging the lug Ma: of this pawl from step bar 31 for releasing the latter which occurs following the operation of arm 63 of the digit indicating wheel mechanism by the pawl 55 engaging the pin 54 of this arm, thus moving the retaining pawl 6| out of engagement from the ratchet wheel 50, but since the release of this wheel has been efiected by the placing of the telephone handset in its cradle from a previous call transmitting operation, the digit indicating wheel 24 remains in normal position with the lug 51 carried thereby abutting with the driving arm 54. It is to be noted that pawl 65 following the operation of pawl 40 for disengaging the lug Man from the step bar 31 is moved to the opposite side of pin 64 so as to permit the arm 63 to return to normal position to cause the reengagement of pawl 5| with ratchet wheel 60 for retaining the digit indicating wheel in any digit indicating position it may have been moved by the gearing mechanism as controlled by the step bar and the yoke Y in this example position Z operator 0 representing the key KIU.

The operation of U-shaped bar H due to the engagement of stud 4| with the cam portion GP of pivoted plate PL is effective to move this plate for positioning its top end portion in the path of lug LS of the non-operated keys as shown in Fig. 4 for preventing the operation of these keys during the transmitting of the train of pulses, represented by key Klfl above-mentioned.

The operation of gear sector I4, the pinion gear unit |5-|6, the pinion 25, gear 23 and th gear sector l8 under the tension of motor spring |2 following the release of step bar 31 by pawl 40, as above described, the step I09: of the step bar engages the free end of arm 44 of yoke Y mounted on pawl 42 respective to key KID to cause a pivotal movement to the yoke Y which is transmitted to the bar 45 by arm 45 of this yoke for closing the shunting contact 41 by the movement of its operi able spring 48 immediately following the operation of the pulsing pawl 29 by the tooth Till of pulsing cam 26 rotated /12 of a turn by the engagement of pinion 25 with the gear IS under control of speed governor SG; The continued pivotal movement of yoke Y following the closing of shunting contact 41 to the position where the free end of this yoke engages the abutment AB formed by slots in the plate PL as shown in Fig. 6, the'lug 55 formed with yoke Y engages the bar 5| and thereby causes the pivotal movement of pawl 42 to the position shown in Fig. 4 for disengaging the roller 43 of key KID which is then returned to normal by the tension of its retractile spring 8.

The rotation of gear l5 of the pinion gear unit |5--|5 for actuating thepulsing cam 26 is effective to rotate the gear 23 and thereby the arm 54 keyed on sleeve 55 for rotating the digit indicator wheel 24 an angular distance corresponding to that of pulsing cam 25 for indicating the number of pulsestransmitted and consequently the digit of the key depressed, the digit wheel remaining in its indicating position by the engagement of retaining pawl 6| with the ratchet wheel 55. The return of the operated key KIE! and the U shaped bar H to normal position under the tension of their respectively associated retractile springs 8 and ID, the U shaped bar H engages the lug L| carried by gear sector l8 for returning the pulsing cam 26 and gear speed multiplier the driving arm 64 for the indicating Wheel to normal position, but the indicating Wheel 're mains in the operated Z operator position while the pawl 65 pivoted at the free end of arm 66 returns from the position shown in Fig. 4 to the position shown in Fig. 7 when the roller 4! carried by the U-bar H frees the camming portion 0P2 of pawl '40 while permitting the lug 4L1: of pawl '40 to move into the path of bar 3'! and the transmitter is now ready for the operation of a succeeding key, but if it is supposed that the telephone handset is placed in its cradle following the telephone conversation, the operation of plunger 69 bygravity causes the pivotal movement of shaft 62 and through the lug 7| carried by arm SBY on shaft 62 imparts a small angular movement to-the arm 63 and thereby to pawl fit for releasing the indicator wheel tire of the call transmitter to give such indications as the transmitting of the call proceeds. The provision of means for giving a visual indication of the last key depressed in the writing operation of a call is one of the novel features of this invention.

What is claimed is:

1. In a call transmitter device, a set of key a pulsing mechanism, a-digit indicator for operating said pulsing mechanism and said indicator drive mechanism.

2. In a call transmitter device, a set of numbered, key members, digit indicating means, a pulsing mechanism, a driving mechanism for said indicating means, a gear speed multiplier mechanism operatively connecting with said pulsing mechanism and said drive mechanism, a step bar movable with saidgear multiplier mechanism for actuating of the operated key a s ucceeding key for actuating said holding 8 means for permitting said indicating means to return to normal.

4. In a call transmitter mechanism a set of digit key members, latching means operatively associated with each of said key members for locking said keys individually into operated position, a pivoted bar actuated by the operation of any one of said key members, a gear sector, a motor spring tensioned by the operation of said bar for actuating said gear sector, a movable step bar, a gear speed multiplier mechanism actuated by said gear sector for actuating said step bar, means pivoted on each of said latching means for operation by the movement of said step bar following the locking of the operated key for controlling the operation of said speed multiplier gear mechanism, and means actuated by said speed multiplier gear mechanism for indicating the digit of the operated key member.

5. In a call transmitter device, a set of digit key members, latching means operatively associated with each of said key members, a bar actuated by the operation of any one of said key members, a gear sector, a motor spring tensioned by the operation of said bar for actuating said gear sector, a gear speed multiplier mechanism actuated by said gear sector, said mechanism comprising a pinion meshing with said gear sector, a gear movable as a unit with said pinion, a second gear sector meshing with said gear in said unit, a bar having staggered steps along one edge thereof, means engaging said bar for preventing its operation during the tensioning of said motor spring, a pulsing contact, a pulsing cam, a pinion engaging the gear of said unit for rotating said pulsing cam for actuating said contact, means carried by each of said latching "mechanism.

6. In a call transmitter device, a set of digit key members, a bar actuated by the operation of transmitted by said pulsing mechanism.

7. In a call transmitter device, a set of digit key members, a bar operated by the movement position,

I an indicator wheel, a

gageable relation with its respective step at the edge of said bar to cause the movement of its latching element for disengaging the depressed key, a pulsing mechanism actuated by the gear of said unit, a shunting contact operated by the yoke carried by the locking element associated with the operated key member for controlling the operation of said pulsing mechanism, and means operable by the movement of the first-mentioned bar for locking the non-operated keys in that position during the operation of said pulsing mechanism.

8. In a call transmitter device, a set of digit key members, a U-shaped bar actuated by the operation of any one of said key members, a gear sector, a motor spring tensioned by the operation of said U-shaped bar for'actuating said gear sector, another gear sector, a gear speed multiplier mechanism for actuating the last-mentioned gear sector, a pulsing mechanism, and an indicator wheel actuated by said gear mechanism, means operable with the last-mentioned gear sector for actuating means positioned by the operation of the depressed key member to cause the release of the depressed key, means for returning said key to normal position, means for returning said U- shaped bar to normal position simultaneously with the return of the operated key and means for holding said indicator wheel to the operated position during the return movement of said gear multiplier mechanism.

9. In a call transmitter device, a set of digit key members, a U-shaped bar actuated by the operation of any one of said key members, a motor spring, a gear speed multiplier mechanism comprising a pair of gear sectors, a pinion gear unit meshing with said gear sectors, a pulsing cam having a pinion engaging the gear of said unit, drive for said wheel having a gear meshing with the gear of said unit and an arm engaging means carried by said wheel, a bar having staggered steps at one of its edges and secured to one of said sectors for movement therewith, means positioned by the operation of any one of said key members for operation by the movement of said bar to cause the return of said gear multiplier mechanism, said pulsing cam and said indicator drive to normal, means for holding said indicating wheel to operated position during the return of said drive to normal for indicating the digit of the key depressed and means actuated by a succeeding key to cause the return of said indicator wheel prior to the operation of said gear multiplier mechanism in response to the operation of said succeeding key.

10. In a call transmitter device, a set of key members disposed in two parallel rows, a gear mechanism, a pulsing mechanism and. an indicator mechanism actuated by said gear mechanism, said indicator mechanism comprising a shaft, a sleeve mounted for free rotation on said shaft, 9. gear keyed on said sleeve meshing with said gear mechanism, an arm keyed to the opposite end of said sleeve, an indicating wheel mounted for free rotation on said shaft having means for engagement with said arm, a ratchet wheel secured to said indicating wheel, another shaft, a pawl pivoted on the last-mentioned shaft for engaging said ratchet wheel to hold the latter in its indicating position, means actuated by the movement of the operated key member for actuating said pawl for releasing said wheel, spring 7 means for returning said wheel to normal wherein the means carried by said wheel engages said arm following the operation of said pawl, and a casing for housing said mechanisms, said casing having a window opening disposed in alignment with the middle disposed keys in said rows through which the numbers on said indicating wheel appear following each setting operation thereoi.

CHARLES D. RICHARD.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,253,650 Richard Aug. 26, 1941 2,374,082 Dowey Apr. 17, 1945

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US2253650 *Mar 24, 1938Aug 26, 1941Bell Telephone Labor IncTelephone call transmitter
US2374082 *Aug 22, 1942Apr 17, 1945Bell Telephone Labor IncTelephone call transmitter
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2945918 *Apr 21, 1958Jul 19, 1960Francis N SteinbachPush button telephone dialing mechanism
US4310729 *Jun 30, 1980Jan 12, 1982Western Electric Company, Inc.Selector switch with common actuator both for circuit selection and for selection indication
Classifications
U.S. Classification379/354, 379/366, 379/364
International ClassificationH04M1/272
Cooperative ClassificationH04M1/272
European ClassificationH04M1/272