US2689521A - Master and block-out sheet gripper means for rotary duplicating machines - Google Patents

Master and block-out sheet gripper means for rotary duplicating machines Download PDF

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US2689521A
US2689521A US332432A US33243253A US2689521A US 2689521 A US2689521 A US 2689521A US 332432 A US332432 A US 332432A US 33243253 A US33243253 A US 33243253A US 2689521 A US2689521 A US 2689521A
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clamping
actuating
rotary
lever
printing
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Ritzerfeld Wilhelm
Ritzerfeld Gerhard
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B41PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41LAPPARATUS OR DEVICES FOR MANIFOLDING, DUPLICATING OR PRINTING FOR OFFICE OR OTHER COMMERCIAL PURPOSES; ADDRESSING MACHINES OR LIKE SERIES-PRINTING MACHINES
    • B41L11/00Apparatus for directly duplicating from hectographic masters in mirror image, i.e. "wet duplicators" for producing positive copies

Definitions

  • the pre ent invention relates' to duplicating macfiiriesfcr printing texts from printing'mastars; for example mirror-script originals; on copy sheets: rotar duplicating machine,
  • I isia side view, partly in section along'the liri'c- D'lof FigIZ, of an embodiment of the in vfe'htlon"; i
  • Fig. 3 illustrates a portion of Fig. 1 in a diffefiit position
  • The" present invention consists in a rotary duplicating machine comprising at least two clamping devices arranged immediately one bethe other" when viewed in the direction of rotationota rotatable printing drum of the machine, the two clamping devices being immovablefrelatively to the printing drum in the axial direction thereof, a clamping jaw of each clampingd'evice being movable in the direction substantiallyperpendicular to the axis of the printing drnm foropening and closing the respective clamping devicew'hereby one of the clamping devices may receive anedge of a printing master and-streamer an additional sheet of material, which may be" ancdge of'an' additional printing mast'enof of acover'ingsheet.
  • Means may be providedfor actuating the clamping jaws independentlyfrom each other, means being providedjfortemporar'ily securing at least one of the clampingjaws in its position in which the respective clamping device is open.
  • the actnating'" means for the clamping jaws' mayeach comprise adeVer'arrangement
  • one of the clampingjaws is tary printing drum
  • a lever arrangement ma be provided outside the printing drumfor control ling the opening and closing movements of the second clamping jaw
  • the lever arrangement comprising a manually operable actuating lever" which isarranged for operating, by means of an angular lever, a control member pivoted to the printing drum, the control member being arranged for actuating a release lever on :a holder for the first clamping jaw.
  • a manually op-- erable actuating lever 2 is movable so as to bear against an abutment 22 or'against an abutment pin 3.
  • a tensionfspring 4 which acts as a dead centre spring
  • an angular lever 5 rotatable around a shaft 6 bears with a portion I acting as a cam against the roll er 8a which is mounted on a control member 8 rotatable around a shaft 9 and mounted on the printing drum I.
  • clamping jaw I1 is rotated around the shaft l6 since the lever arm l3 engages the cam follower" roller Ila mounted on the second clamping jaw I1 whereby a slot I9 is formed between'thefir'st" clamping jaw I4 and the second clamping jaw I1 so that an edge of an additional printing master" or of a covering sheet 2 may freely be inserted into the slot l9.
  • Fig. 3 shows the first clamping jaw hijafterit" has been opened by means of a member 2 I actuatable in a manner known per se, so that the fi rs't clamping jaw l4 can be operated independently of the operating elements for the second clamp; ing jaw l1 and can be brought into theposition 3 shown in Fig. 3 in which it is ready to receive an edge of the printing master [5.
  • a rotary duplicating machine in combination, a rotary printing drum; a first clamping member movably mounted on said printing drum for clamping a printingmaster and having a clamping portion; a second clamping member having a clamping portion and being attached to said first clamping member movable relative thereto between a releasing position and a clamping position in which said clamping portions engage each other for clamping an additional sheet; spring means urging said second clamping member into said clamping position; actuating means connected to said second clamping member for moving the same to said releasing position, said actuating means being mounted on said printing drum and having an actuating portion moving along a circular path during rotation of said printing drum; a stationary support; and operating means mounted on said stationary support for movement between an inoperative position and an operative position, and having a portion moving across said path of said actuating portion and engaging the same in a predetermined position of said rotary drum so that movement of said operating means to said operative position eiiects movement of said actuating means
  • a rotary duplicating machine in combination, a rotary printing drum; 2. first clamping member movably mounted on said printing drum for clamping a printing master and having a clamping portion; a second clamping member having a clamping portion and being attached to said first clamping member movable relative thereto between a releasing position and a clamping position in which said clamping portions engage each other for clamping an additional sheet; spring'means urging said second clamping member into said clamping position; actuating means connected to said second clamping member for moving the same to said releasing position, said actuating means being mounted on said printing drum and having an actuating portion moving along a circular path during rotation of said printing drum; a stationary support; manually operated operating means mounted on said stationary support for movement between an inoperative position and an operative position, and having a portion moving across said path of said actuating portion and engaging the same in a predetermined position of said rotary drum so that-movement of said operating means to said operative position efiects movement of said actu
  • a rotary duplicating machine in combination, a rotary printing drum; a first clamping member movably mounted within said printing drum for clamping a printing master and having a clamping portion; a shaft means extending parallel to the axis of said rotary printing drum and being mounted on said first clamping member; a second clamping member having a clamping portion and being mounted on said shaft means on said first clamping member rockable between a releasing position and a clamping position in which said clamping portions engage each other for clamping an additional sheet; spring means urging said second clamping member into said clamping position; actuating means connected to said second clamping member for moving the same to said releasing position, said actuating means including an actuating shaft mounted on said printing drum, a lever arm secured to said actuating shaft and having an end portion engaging said second clamping member for turning the same to said releasing position when said actuating shaft is turned, a lever means connected to said actuating shaft for turning the same, said lever means having an actuating portion moving along a
  • a rotary duplicating machine in combination, a rotary printing drum; a first clamping member movably mounted within said printing drum for clamping a printing master and having a clamping portion; a shaft means extending parallel to the axis of said rotary printing drum and being mounted on said first clamping member; a second clamping member having a clamping portion and being mounted on said shaft means on said first clamp-ing member rockable between a releasing position and a clamping posi-.
  • actuating means connected to said second clamping member 'formoving the Same to said releasing position, said actuating means including an actuating shaft mounted on said printing drum, a lever arm se cured to said actuating shaft and having an end portion engaging said second clamping member for turning the same to said releasing position when said actuating shaft is turned, a lever means connected to said actuating shaft for turning the same, said lever means having an actuating portion moving along a circular path during rotation of said printin drum; a stationary support; manually operated operating means mounted on said stationary support for movement between an inoperative position and an operative position, and having a cam portion moving across said path of said actuating portion and engaging the same in a predetermined position of said rotary drum so that movement of said operating means to said operative position effects movement of said actuating means and turning of said actuating shaft, and thereby movement of said second clamping member to
  • lever means include another lever arm secured to said actuating shaft, a control member pivotally mounted on said printing drum and having a forked portion engaging the free end of said other lever arm, and a cam follower mounted on said control member and constituting said actuatin portion; and wherein said cam portion of said manually operated operating means cooperates with said cam follower.
  • said manually operated operatin means include a first lever pivotally mounted on said stationary support and having a forked end portion; a second double armed lever turnably mounted on said stationary support and having at one end thereof said cam portion; a pin secured to the other end of said second double armed lever and projecting into said forked end portion of said first lever; and comprising stop means engaging said first lever in said operative and inoperative positions of said operating means; and a dead-center spring secured at one end thereof to said stationary support and at the other end thereof to said first lever for urging the same into engagement with said stop means when said first lever is moved out of a dead-center position in which said dead-center spring is located in a plane passing through the turning axis of said first lever.

Description

Sept. 21, 1954 w, RITZERFELD ET AL 2,689,521
MASTER AND BLOCK-OUT SHEET GRIPPER MEANS FOR ROTARY DUPLICATING MACHINES Filed Jan. 21, 1953 MLHsLm KrrzERFELD Ann GERHARD RITZERFELD Patented Sept. 21, 1954 UNITED-1 T, STATES: PATENT" OFFICE,
' MAs rEitA n moor- 531? snnnrcmrrnn ME ANS'IF OR ROTARY DUPi-JIGATING l Wilhelm Ritzerfel d, Berlin-Dahlem, and Gerhard" Ritzerfeld, Berli'n-Grunewald, Germany Claims pri'ority application Germany Aiilil z l, 1952 7 Claims; (01. 101-432) v The pre ent invention relates' to duplicating macfiiriesfcr printing texts from printing'mastars; for example mirror-script originals; on copy sheets: rotar duplicating machine,
the. p'rintingma'ster is attached to a rotary printmg? by means" of a clamping device com prising a movable clamping. jaw forclosing and opening 'the' clamping device: The closing and opening" of theclainping device for attaching aprinting, master and for releasing the same after the, printing: been completed is eifected in mawn manner by a manually operable actuatifigi leve'r; For certain duplicating purposes it is necessajry to attach more" than one printing mastertr a printing master and a sheet covering the saniein part to the printingdrum;
It'is anobject of the invention to provide meansfor'fac'ilitatingattaching more than one nntmgmaster, or "a printing master'and' a coveringisheet; to a rotatable printingdrum'ofa rotary; duplicating machine.
Other" objects and advantages will become apparent-from the following detailed description of an" embodiment of the invention, when read in conjunction with the appended drawings in wines:
I isia side view, partly in section along'the liri'c- D'lof FigIZ, of an embodiment of the in vfe'htlon"; i
2 a section along the line A-B of 1;
Fig. 3 illustrates a portion of Fig. 1 in a diffefiit position;
The" present invention consists in a rotary duplicating machine comprising at least two clamping devices arranged immediately one bethe other" when viewed in the direction of rotationota rotatable printing drum of the machine, the two clamping devices being immovablefrelatively to the printing drum in the axial direction thereof, a clamping jaw of each clampingd'evice being movable in the direction substantiallyperpendicular to the axis of the printing drnm foropening and closing the respective clamping devicew'hereby one of the clamping devices may receive anedge of a printing master and-streamer an additional sheet of material, which may be" ancdge of'an' additional printing mast'enof of acover'ingsheet. Means may be providedfor actuating the clamping jaws independentlyfrom each other, means being providedjfortemporar'ily securing at least one of the clampingjaws in its position in which the respective clamping device is open. The actnating'" means for the clamping jaws'mayeach comprise adeVer'arrangement;
Advantageously, one of the clampingjaws is tary printing drum, a lever arrangement ma be provided outside the printing drumfor control ling the opening and closing movements of the second clamping jaw, the lever arrangementcomprising a manually operable actuating lever" which isarranged for operating, by means of an angular lever, a control member pivoted to the printing drum, the control member being arranged for actuating a release lever on :a holder for the first clamping jaw.
In a predetermined, initial, position illustrated in the drawings of a rotatable printing drum 1 of a rotary duplicating machine; a manually op-- erable actuating lever 2 is movable so as to bear against an abutment 22 or'against an abutment pin 3. When the said lever 2 is moved to bear against the abutment pin 3 as illustrated in Fig. 1, it is secured in this position by atensionfspring 4 which acts as a dead centre spring, while an angular lever 5 rotatable around a shaft 6 bears with a portion I acting as a cam against the roll er 8a which is mounted on a control member 8 rotatable around a shaft 9 and mounted on the printing drum I. ,A fork I I of the control member Brotates a release lever ID in the direction of the arrow E. The release lever 10' is" keyed to a'shaft l2 to which also'a clamp-openingm'emberl3 is keyed. On a first clamping jaw M; which servesfor attaching a printing master I5" i to the printing drum 1, a second clamping ja'w'j clamping jaw [4. When the release lever In and" therewith the clamp-opening member l3 are retated in the direction of the arrowE, the second. clamping jaw I1 is rotated around the shaft l6 since the lever arm l3 engages the cam follower" roller Ila mounted on the second clamping jaw I1 whereby a slot I9 is formed between'thefir'st" clamping jaw I4 and the second clamping jaw I1 so that an edge of an additional printing master" or of a covering sheet 2 may freely be inserted into the slot l9.
Fig. 3 shows the first clamping jaw hijafterit" has been opened by means of a member 2 I actuatable in a manner known per se, so that the fi rs't clamping jaw l4 can be operated independently of the operating elements for the second clamp; ing jaw l1 and can be brought into theposition 3 shown in Fig. 3 in which it is ready to receive an edge of the printing master [5.
For moving the clamping jaw I! from its open position shown in Fig. 1 into its closed position, the manually operable actuating lever 2 is rotated until it bears against the abutment pin 22.
It should be clearly understood that the embodiment described and illustrated is given by way of example. Many modifications, additions and omissions are possible without departing from the spirit and scope of the present invention.
We claim:
1. In a rotary duplicating machine, in combination, a rotary printing drum; a first clamping member movably mounted on said printing drum for clamping a printingmaster and having a clamping portion; a second clamping member having a clamping portion and being attached to said first clamping member movable relative thereto between a releasing position and a clamping position in which said clamping portions engage each other for clamping an additional sheet; spring means urging said second clamping member into said clamping position; actuating means connected to said second clamping member for moving the same to said releasing position, said actuating means being mounted on said printing drum and having an actuating portion moving along a circular path during rotation of said printing drum; a stationary support; and operating means mounted on said stationary support for movement between an inoperative position and an operative position, and having a portion moving across said path of said actuating portion and engaging the same in a predetermined position of said rotary drum so that movement of said operating means to said operative position eiiects movement of said actuating means, and thereby movement of said second clamping member to said releasing position, when said rotary drum is in said predetermined angular position with respect to said operating means, while said spring means move said second clamping member to said clamping position when said rotary drum turns out of said predetermined angular position.
2. In a rotary duplicating machine, in combination, a rotary printing drum; 2. first clamping member movably mounted on said printing drum for clamping a printing master and having a clamping portion; a second clamping member having a clamping portion and being attached to said first clamping member movable relative thereto between a releasing position and a clamping position in which said clamping portions engage each other for clamping an additional sheet; spring'means urging said second clamping member into said clamping position; actuating means connected to said second clamping member for moving the same to said releasing position, said actuating means being mounted on said printing drum and having an actuating portion moving along a circular path during rotation of said printing drum; a stationary support; manually operated operating means mounted on said stationary support for movement between an inoperative position and an operative position, and having a portion moving across said path of said actuating portion and engaging the same in a predetermined position of said rotary drum so that-movement of said operating means to said operative position efiects movement of said actuating means, and thereby movement of said second clamping member to said releasing position, when said rotary drum is in said predetermined angular position with respect to said operating means, while said spring means move said second clamping member to said clamping position when said rotary drum turns out of said predetermined angular position; and means for arresting said manually operating means in said inoperative and operative positions thereof.
3. In a rotary duplicating machine, in combination, a rotary printing drum; a first clamping member movably mounted within said printing drum for clamping a printing master and having a clamping portion; a shaft means extending parallel to the axis of said rotary printing drum and being mounted on said first clamping member; a second clamping member having a clamping portion and being mounted on said shaft means on said first clamping member rockable between a releasing position and a clamping position in which said clamping portions engage each other for clamping an additional sheet; spring means urging said second clamping member into said clamping position; actuating means connected to said second clamping member for moving the same to said releasing position, said actuating means including an actuating shaft mounted on said printing drum, a lever arm secured to said actuating shaft and having an end portion engaging said second clamping member for turning the same to said releasing position when said actuating shaft is turned, a lever means connected to said actuating shaft for turning the same, said lever means having an actuating portion moving along a circular path during rotation of said printing drum; a stationary sup-port; and operating means .mounted on said stationary support for movement between-an inoperative position and an operative position, and having a cam portion moving across said path of said actuating portion and engaging the same in a predetermined position of said rotary drum so that movement of said operating means to said operative position effects movement of said actuating means and turning of said actuating shaft, and thereby movement of said second clamping member to said releasing position, when said rotary drum is in said predetermined angular position with respect to said operating means, while said spring means move said second clamping member to said clamping position when said rotary drum turns out of said predetermined angular position.
4. In a rotary duplicating machine, in combination, a rotary printing drum; a first clamping member movably mounted within said printing drum for clamping a printing master and having a clamping portion; a shaft means extending parallel to the axis of said rotary printing drum and being mounted on said first clamping member; a second clamping member having a clamping portion and being mounted on said shaft means on said first clamp-ing member rockable between a releasing position and a clamping posi-.
tion in which said clamping portions engage each other for clamping an additional sheet; sprin means urging said second clamping member into said clamping position; actuating means connected to said second clamping member 'formoving the Same to said releasing position, said actuating means including an actuating shaft mounted on said printing drum, a lever arm se cured to said actuating shaft and having an end portion engaging said second clamping member for turning the same to said releasing position when said actuating shaft is turned, a lever means connected to said actuating shaft for turning the same, said lever means having an actuating portion moving along a circular path during rotation of said printin drum; a stationary support; manually operated operating means mounted on said stationary support for movement between an inoperative position and an operative position, and having a cam portion moving across said path of said actuating portion and engaging the same in a predetermined position of said rotary drum so that movement of said operating means to said operative position effects movement of said actuating means and turning of said actuating shaft, and thereby movement of said second clamping member to said releasin position, when said rotary drum is in said predetermined angular position with respect to said operating means, while said spring means move said second clamping member to said clamping position when said rotary drum turns out of said predetermined angular position; and means for arresting said manually operating means in said inoperative and operative positions thereof.
5. An arrangement as claimed in claim 4 wherein said lever means include another lever arm secured to said actuating shaft, a control member pivotally mounted on said printing drum and having a forked portion engaging the free end of said other lever arm, and a cam follower mounted on said control member and constituting said actuatin portion; and wherein said cam portion of said manually operated operating means cooperates with said cam follower.
6. An arrangement as claimed in claim 5 wherein said manually operated operatin means include a first lever pivotally mounted on said stationary support and having a forked end portion; a second double armed lever turnably mounted on said stationary support and having at one end thereof said cam portion; a pin secured to the other end of said second double armed lever and projecting into said forked end portion of said first lever; and comprising stop means engaging said first lever in said operative and inoperative positions of said operating means; and a dead-center spring secured at one end thereof to said stationary support and at the other end thereof to said first lever for urging the same into engagement with said stop means when said first lever is moved out of a dead-center position in which said dead-center spring is located in a plane passing through the turning axis of said first lever.
7. In a rotary duplicating machine, an arrange ment as claimed in claim 1 wherein said rotary printing drum is formed with a recess, and wherein said first clamping member is arranged in said recess of said printing drum.
References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,220,282 Ritzerfeld Nov. 5, 1940 2,260,464 Kropp Oct. 28, 1941 2,536,604 Jagger Jan. 2, 1951 2,599,252 Gerlach June 3, 1952
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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2813482A (en) * 1954-12-20 1957-11-19 Addressograph Multigraph Clamp for master sheets of rotary printing machines
US2937593A (en) * 1954-12-23 1960-05-24 Ritzerfeld Wilhelm Printing foil attaching arrangement
US2990772A (en) * 1957-08-14 1961-07-04 Davidson Corp Plate clamping means for printing machines
US3199452A (en) * 1960-10-28 1965-08-10 Gericke Erich Foil clamping devices for clamping printing foils on the cylinder of duplicating machines
US3422756A (en) * 1965-09-30 1969-01-21 Xerox Corp Paper support and registration means for reproduction machine
US3941054A (en) * 1971-10-06 1976-03-02 Heyer Inc. Stencil gripping apparatus for a duplicating machine

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2220282A (en) * 1937-10-07 1940-11-05 Ritzerfeld Wilhelm Apparatus for clamping mirrorscript originals in duplicating machines and method relating thereto
US2260464A (en) * 1940-05-31 1941-10-28 Victor Adding Machine Co Duplicating machine
US2536604A (en) * 1945-08-17 1951-01-02 Jagger Hubert Moistening device for duplicating machines
US2599252A (en) * 1947-09-27 1952-06-03 Block & Anderson Ltd Master clip opening means for rotary duplicating machines

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2220282A (en) * 1937-10-07 1940-11-05 Ritzerfeld Wilhelm Apparatus for clamping mirrorscript originals in duplicating machines and method relating thereto
US2260464A (en) * 1940-05-31 1941-10-28 Victor Adding Machine Co Duplicating machine
US2536604A (en) * 1945-08-17 1951-01-02 Jagger Hubert Moistening device for duplicating machines
US2599252A (en) * 1947-09-27 1952-06-03 Block & Anderson Ltd Master clip opening means for rotary duplicating machines

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2813482A (en) * 1954-12-20 1957-11-19 Addressograph Multigraph Clamp for master sheets of rotary printing machines
US2937593A (en) * 1954-12-23 1960-05-24 Ritzerfeld Wilhelm Printing foil attaching arrangement
US2990772A (en) * 1957-08-14 1961-07-04 Davidson Corp Plate clamping means for printing machines
US3199452A (en) * 1960-10-28 1965-08-10 Gericke Erich Foil clamping devices for clamping printing foils on the cylinder of duplicating machines
US3422756A (en) * 1965-09-30 1969-01-21 Xerox Corp Paper support and registration means for reproduction machine
US3941054A (en) * 1971-10-06 1976-03-02 Heyer Inc. Stencil gripping apparatus for a duplicating machine

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