US3888394A - Toner dispensing device - Google Patents

Toner dispensing device Download PDF

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Publication number
US3888394A
US3888394A US471779A US47177974A US3888394A US 3888394 A US3888394 A US 3888394A US 471779 A US471779 A US 471779A US 47177974 A US47177974 A US 47177974A US 3888394 A US3888394 A US 3888394A
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US
United States
Prior art keywords
spring
toner
dispensing device
slit
toner powder
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
US471779A
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English (en)
Inventor
Susumu Tanaka
Yuji Enoguchi
Hidetoshi Kawabata
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.)
Minolta Co Ltd
Original Assignee
Minolta Co Ltd
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 Minolta Co Ltd filed Critical Minolta Co Ltd
Application granted granted Critical
Publication of US3888394A publication Critical patent/US3888394A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G15/00—Apparatus for electrographic processes using a charge pattern
    • G03G15/06—Apparatus for electrographic processes using a charge pattern for developing
    • G03G15/08—Apparatus for electrographic processes using a charge pattern for developing using a solid developer, e.g. powder developer
    • G03G15/0822—Arrangements for preparing, mixing, supplying or dispensing developer
    • G03G15/0887—Arrangements for conveying and conditioning developer in the developing unit, e.g. agitating, removing impurities or humidity
    • G03G15/0891—Arrangements for conveying and conditioning developer in the developing unit, e.g. agitating, removing impurities or humidity for conveying or circulating developer, e.g. augers
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G15/00—Apparatus for electrographic processes using a charge pattern
    • G03G15/06—Apparatus for electrographic processes using a charge pattern for developing
    • G03G15/08—Apparatus for electrographic processes using a charge pattern for developing using a solid developer, e.g. powder developer
    • G03G15/0822—Arrangements for preparing, mixing, supplying or dispensing developer
    • G03G15/0865—Arrangements for supplying new developer
    • G03G15/0875—Arrangements for supplying new developer cartridges having a box like shape
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G15/00—Apparatus for electrographic processes using a charge pattern
    • G03G15/06—Apparatus for electrographic processes using a charge pattern for developing
    • G03G15/08—Apparatus for electrographic processes using a charge pattern for developing using a solid developer, e.g. powder developer
    • G03G15/0822—Arrangements for preparing, mixing, supplying or dispensing developer
    • G03G15/0877—Arrangements for metering and dispensing developer from a developer cartridge into the development unit
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G15/00—Apparatus for electrographic processes using a charge pattern
    • G03G15/06—Apparatus for electrographic processes using a charge pattern for developing
    • G03G15/08—Apparatus for electrographic processes using a charge pattern for developing using a solid developer, e.g. powder developer
    • G03G15/0822—Arrangements for preparing, mixing, supplying or dispensing developer
    • G03G15/0877—Arrangements for metering and dispensing developer from a developer cartridge into the development unit
    • G03G15/0881—Sealing of developer cartridges
    • G03G15/0886—Sealing of developer cartridges by mechanical means, e.g. shutter, plug

Definitions

  • ABSTRACT A toner dispensing device for use in a developing apparatus of a dry-copying process photocopying machine which comprises a toner dispenser casing having a lowermost projecting portion with a slit.
  • a container for toner powder removably received in the casing a coil spring accommodated in the projecting portion above the slit, means for pulling the spring, means for adjusting the tension of the spring and a driving device for the pulling means.
  • the spring is adapted intermittently to expand by the pulling means so that gaps are formmed between the neighboring turns of the spring for the toner powder to pass through and to contract so as to close the gaps to suspend feeding of toner powder.
  • FIG. 2 6 Claims, 5 Drawing Figures PATENTEDJUN l 0 ms SHEET FIG! FIG. 2
  • FIG 5 TONER DISPENSING DEVICE
  • the present invention relates to a dry-copying process photo-copying apparatus, and more particularly to a unitary toner dispensing device for use therein.
  • the latent image is developed at a developing station by developing material comprising magntizable carrier material and electro seopic toner powder to produce an electroscopic toner powder image in the configuration of the latent image on the photoreceptor surface for tansfer onto a copy paper sheet so as to obtain a copy of the original image thereon.
  • the used developing material scraped off a developing roller in preparation for subsequent copying must be replenished with fresh toner powder from the toner dispenser to maintain a fixed toner concentration, since the toner powder in the developing material is gradually exhausted by the repeated developings, which results in inferior development due to low toner concentration in the developing material.
  • a toner dispensing device which comprises a rotary member such as a roller or a brush accommodated at the bottom portion of the toner dispenser casing so as to be driven by a motor, and a slit of a fixed width formed at said bottom portion immediately below the rotary member, with the rotary member adapted to rub against the slit at speeds of rotation variable depending upon requirements, by controlling voltage to be applied to the DC motor, thus enabling a desired amount of toner powder to be supplied to the developer material through the slit.
  • a rotary member such as a roller or a brush accommodated at the bottom portion of the toner dispenser casing so as to be driven by a motor
  • a slit of a fixed width formed at said bottom portion immediately below the rotary member with the rotary member adapted to rub against the slit at speeds of rotation variable depending upon requirements, by controlling voltage to be applied to the DC motor, thus enabling a desired amount of toner powder to be supplied to the developer material through the slit.
  • a motor with larger driving force is employed to over come the above inconvenience, which is also disadvantageous due to resultant larger size of the apparatus and higher cost for manufacturing.
  • some conventional devices adopt a constant speed for the rotary member with variable slit widths for supplying desired amount of toner powder, but such devices also have such disadvantages that, if the width of the slit is adjusted to be too narrow, clogging of the slit with the toner powder may result, making it impossible to feed proper amount of toner powder smoothly with adjustment of the slit width complicated.
  • an essential object of the present invention is to provide a toner dispensing device which is accurate in functioning for uniform and positive replenishment of toner powder wherein the amount of toner powder to be fed is readily adjustable with substatial elimination of the disadvantages inherent in the conventional toner dispensing devices.
  • Another important object of the present invention is to provide a toner dispensing device of the above de scribed type which is simple in construction and compact in size.
  • a still further object of the present invention is to provide a toner dispensing device of the above described type which can be produced at low cost and is easy of maintenance.
  • the toner dispensing device comprises a dispenser casing retained in an opening formed on the top wall of a developer housing immediately above a stirrer in the developing device with the casing having a projecting portion of semi-circular cross section at the lower part of said casing, which lower part is provided with a slit at the extreme lower portion thereof for the toner powder to pass therethrough, a container for storing the toner powder removably received in and in communication with the casing, a coil spring with neighboring turns thereof contacting with each other in the normal contracted state of the spring, which spring is accommodated in the lower part of the casing immediately above the slit, means of pulling one end of the spring with the other end of the spring connected to means for adjusting the tension of the spring and a driving device for the pulling means.
  • the pulling means further includes a slidable plate which is slidably mounted on a guide plate secured to one side wall of the developer housing and which is provided with a rack in the undersurface thereof, a cable line with one end fixed to the slidable plate and the other end thereof connected to one end of the spring through a pulley.
  • the rotation of a motor of the driving device is transmitted, through a chain and a plurality of sprokets and gears, to a special gear having a toothed portion and a toothless portion, the toothed portion of which is adapted to engage the rack of the slidable plate.
  • the other end of the spring is connected, by a cable line, to an adjusting knob of the tensioin adjusting means through a pulley, which knob is adapted to adjust the tension of the spring in its contracted state to such an extent that the neighboring turns of the spring remain contacting with each other so as not to pass the toner powder therethrough.
  • the slidable plate which is in engagement with the toothed portion of the special gear is moved in the direction to pull the spring, thereby forming gaps between neighboring turns of the coil spring for the toner powder to pass therethrough.
  • the toothless portion of the gear reaches the rack, the engagement therebetween is released and the slidable plate immedately returns to its original position with the gaps between the neighboring turns of the spring again closed, consequently feeding of the toner powder being suspended.
  • toner powder can be fed uniformly and positively by simply expanding or contracting the spring with the amount of the toner powder to be fed easily controlled by adjusting the tension adjusting means.
  • FIG. 1 is a schematic cross sectional view of a toner dispensing device according to an embodiment of the present invention
  • FIG. 2 is a rear elevational view partly in section of the device shown in FIG. I,
  • FIG. 3 is a perspective view showing mechanism associated with a pulling means employed in the device in FIG. I,
  • FIG. 4 is a side clcvational view, on an enlarged scale, of a rack and gears associated therewith employed in the device in FIG. 3, and
  • FIG. 5 is a perspective view showing mechanism associated with a tension adjusting means of the device in FIGv 1.
  • a toner dispensing device A as applied to an electrostatic latent image developing device D of :1 copying apparatus
  • the housing 7 of the developing device D extends the width of a known photoreceptor drum l0 driven by a conventional means and is provided with an opening C adjacent to a photoreceptor surface of the drum l0 whcreat development of a latent image formed on the surface 10' is effected and another opening 7e in which the toner dispenser A is received for replenishing toner powder depleted from developing material during development of the latent image.
  • a sump 7c for storing developing material 9 comprising magnetizable carrier material and electroscopic toner particles at a lowermost portion of the developer housing 7.
  • the developer housing 7 is disposed adjacent to the photoreceptor surface 10' and suitably secured to the frames of the copying appa ratus (not shown).
  • the toner powder dispenser A is retained by the edge 7fof the opening 7e which is formed on the top wall 7d of the developer housing 7 adjacent to the rear end thereof remote from the opening C.
  • the developer housing 7 includes a magnetic roller 1 adjacent to thc photoreceptor surface 10' which roller 1 comprises an outer cylinder 2 of a nonmagnetic material. such as aluminum or brass, extending the width of the developer housing 7 and having minute concave and cover portions formed on the outer periphery thereof for better friction. and three elongated bar magnets 4 which are housed in the cylinder 2 and extend nearly the full length of the latter.
  • a magnetic roller 1 adjacent to thc photoreceptor surface 10' which roller 1 comprises an outer cylinder 2 of a nonmagnetic material. such as aluminum or brass, extending the width of the developer housing 7 and having minute concave and cover portions formed on the outer periphery thereof for better friction.
  • three elongated bar magnets 4 which are housed in the cylinder 2 and extend nearly the full length of the latter.
  • the bar magnets 4 are fixedly mounted on a bar 3 which is appropriately secured to the side walls 70: and 7b of the housing 7 (not shown) with the magnets 4 arranged in such positions that the magnetic force fields thereof intersect to form magnetic brush bristles of the developing material on the surface of the outer cylinder 2, which outer cylinder 2 of nonmagnetic material is mounted for rotation about a shaft 5 by means of suitable bearing surfaces carried by side frames of the housing 7 (not shown), so that. upon rotation of the outer cylinder 2 around the stationary elongated bar magnets 4, the magnetic force fields of the latter project through the wall of the outer cylinder 2 to form the developing ma terial pooled on the sump 7c into magnetic brush bris tles on the outer periphery of the cylinder 2.
  • the magnetic brush bristles thus formed are adapted to rub i slightly against the photoreceptor surface it) as the latter rotates counterclockwise in FIG. 1 to visualize the latent image formed on the surface 10.
  • the developing device D is further provided, in the housing 7 thereof below the toner dispenser A, with a rotary stirrer ll formed by suitably securing a plurality of vanes 13 tangentially on the outer periphery of a shaft 12, which shaft 12 is rotatably supported in the side walls 7a and 7b by bearings 14a and I4! (FIGSv 3 and 5)
  • the rotary stirrer II which rotates in the direction of the arrow in FIG.
  • I is adapted, during rotation thereof, to mix fresh toner powder cascaded thcreover from the dispenser A with the used developer material of low toner concentration scraped off the cyilindcr 2 by a scraper 6 so as to keep the toner concentration in the developing material 9 pooled in the sump 7c at a uniform level.
  • the toner dispenser A of the present invention disposed above the stirrer 11 as described above mainly comprises a casing l5 of a trough shape retained in the edge 7f of the opening of the dispenser housing 7 and is provided with a small downwardly projecting portion 16 of a semi-circular cross section having a slit 17 at the lowermost portion thereof which faces the stirrer 11, a container 18 of rectangular cross section which removably fits into the edge 15' of the casing 15 which is in communication with the former.
  • a coil spring 20 with its turns contacting with one another in the contracted state of the spring 20, which spring 20 is received above the slit 17.
  • the spring 20 is received in the projecting portion 16 of the casing 15 in such a manner that it can be ex panded or contracted without obstruction therein with one end thereof connected to the pulling means 24 through a cable line 21a and with the other end thereof connected to the tension adjusting means 43 through a cable line 21b.
  • the toner powder 19 is adapted to be cascaded over the stirrer 1] through the gaps formed between neigh boring turns of the spring 20, and through the slit 17.
  • the pulling means 24 mounted on the side wall 70 of the developer housing 7 further comprises a guide plate 25 ofl shaped cross section which has a guide portion 26 provided at its outer face and is suitably fixed to the wall 7a at the base 25' thereof, a slidable plate 24 having a T shaped groove 27' formed in the undersurface thereof which groove 27 is slid-ably titted into the corresponding guide portion 26 of similar T shape of the guide plate 25, the cable line 21:: one end of which is secured to the slidable plate 24 by a set screw 28 with the other end thereof connected to one end of the spring through a pulley 23a rotatably mounted on a bracket 22a fixed on the wall 7a, and the driving device 32 with associated mechanisms described below.
  • a rack 29 (FIG. 4) is cut in the under-surface of the slidable plate 27 which rack 29 is adapted to engage a gear 41 with a toothless portion 42.
  • An elongated slot 30 is formed in the outer face of the slidable plate 27 in the direction parallel to the movement of the plate 27, while a stopping pin 31 which extends outwardly at right angles from the surface of the guide portion 26 of the guide plate is adapted to project into the slot to limit the movement of the plate 27 toward the left due to tension of the spring 20.
  • a sprocket 35 fixed to a driving shaft 34 of a motor 33 is connected to a sprocket 36 rotatably mounted on the side wall 7 by a chain 37 through sprockets 36X, 36Y and 36Z which are also rotatably mounted on the wall 7, while a gear 38 integrally fixed to the sprocket 36 is adapted to engage, through an idle gear 39, with a gear 40 integrally fixed to the gear 41 having a toothless portion 42 which gear 41 is also rotatably mounted on the wall 7. Consequently, the turning force of the motor 33 is transmitted to the gear 41 through the chain 37, the sprocket 36, and the gears 38, 39 and 40.
  • the tension adjusting means 43 which is mounted on the side opposite to the tension means 24, namely, on the side wall 7b of the developer housing 7 has a adjusting knob 48, which is slideable and fixable for positioning in an elongated slot 46 formed in an adjusting plate 44 of rectangular shape with scales 45 graduated along the long side edge of the plate 44.
  • the end of the cable line 21b whose other end is fixed to the other end of the spring 20 is fixed to the adjusting knob 48 through a slot 47 formed in the short side edge of the plate 44 and in communication with the longated slot 46.
  • the intermediate portion of the cable line 21b is passed over a pulley 23b rotatably mounted on a bracket 22b secured to the side wall 7b.
  • the tension of the spring 20 in the contracted state thereof varies accordingly, whereby the gaps between the neighboring turns of the spring 20 vary as the slidable plate 27 slide along the guide portion 26 of the gide plate 25 so as to regulate the feeding amount of the toner 19 through the slit 17.
  • a maximum tension to be applied to the spring at its contracted state is required to be within such a range that the spring 20 is not expanded more than necessary without forming gaps between neighboring turns thereof through which toner powder may pass.
  • the spring 20 upon rotation of the motor 33, the spring 20 is adapted to expand and contract intermittently as described hereinabove to replenish the toner powder 19 via the slit 17 into the developing material 9 in the sump 7c through the gaps formed between neighboring turns of the spring 20 upon expansion of said spring 20.
  • the toner powder 19 falling by its own weight falls more positively due to vibrations of the spring 20 caused upon returning of the slidable plate 27 to its original position. it is particularly effective in cases where the toner powder 19 is packed under pressure in the container l8.
  • Adjustment of the toner feeding amount can be made by varying the number of revolution of the driving means 32 and also by adjusting the tension adjusting means 43. Namely, the number of expansion and contraction of the spring 20 per unit time is increased or decreased through variation of the number of revolution of the above driving device 32.
  • the toner dispensing device of the present invention is of simple construction wherein the coil spring whose neighboring turns normally contact with each other is accommodated at the bottom portion immediately above the slit of the toner dispenser casing and is adapted to expand and contract intermittently by the driving device. the toner powder being adapted to fall through the gaps formed between the neighboring turns of the spring upon expansion thereof and through the slit in the dispenser casing.
  • the toner feeding amount can be regulated readily by adjusting the tension adjusting means or by varying the number of revolution of the driving means, such inconveniences as clogging of the slit with the toner powder due to excessive throttling of the slit opening experienced in the prior art is prevented so long as the width of the slit is formed in advance to such a width as the clogging with the toner powder may not be caused.
  • a toner dispensing device for use in a developing apparatus of an electrostatic copying machine which comprises a dispenser casing retained in an opening formed on a wall of said developing apparatus, said dispensing casing having a slit formed in a bottom portion thereof, a container for toner powder removably received in and communicating with said dispenser casing, and a coil spring provided at the bottom of said dispenser casing above said slit with neighboring turns of said spring adapted to contact with each other in the contracted state of said spring, an improvement thereof for feeding toner powder uniformly and positively which comprises means for pulling one end of said spring for expansion thereof so that gaps are formed between said neighboring turns of said spring for toner powder to pass through said gaps and said slit. said pulling means being adapted to release pulling intermittently so as to allow said spring to be contracted with said neighboring turns thereof closed in order to suspend feeding of toner powder.
  • said tension adjusting means further comprises an adjusting plate with an elongated slot formed therein, and a knob which is slidable in said elongated slot and which can be fixed at desired positions in said elongated slot, and a cable line fixedly connected at one end thereof, to said knob with the other end of said cable line fixedly connected to the other end of said spring.
  • said special gear when engaged with said rack at the toothed portion thereof. being adapted to move said slidable plate in a direction to expand said spring with said slidable plate adapted to return to the original position thereof immediately when said toothless portion of said special gear reaches said rack to release engagement therebetween.

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Dry Development In Electrophotography (AREA)
  • Filling Or Emptying Of Bunkers, Hoppers, And Tanks (AREA)
US471779A 1973-05-28 1974-05-20 Toner dispensing device Expired - Lifetime US3888394A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP1973062561U JPS5329151Y2 (enrdf_load_stackoverflow) 1973-05-28 1973-05-28

Publications (1)

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US3888394A true US3888394A (en) 1975-06-10

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Application Number Title Priority Date Filing Date
US471779A Expired - Lifetime US3888394A (en) 1973-05-28 1974-05-20 Toner dispensing device

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US (1) US3888394A (enrdf_load_stackoverflow)
JP (1) JPS5329151Y2 (enrdf_load_stackoverflow)
DE (1) DE2425368C3 (enrdf_load_stackoverflow)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4353485A (en) * 1979-02-15 1982-10-12 Aluminum Company Of America Apparatus for conveying particulate material by spring expansion and contraction
US5918539A (en) * 1998-05-14 1999-07-06 So.Ge. Ca. S.N.C. Device for making patterns or images having predetermined shape using powder substances
US20050276636A1 (en) * 2004-06-14 2005-12-15 Proweal Counter Corp. Magnetic roller for image developing means

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5614523Y2 (enrdf_load_stackoverflow) * 1975-05-21 1981-04-06
JPS559940U (enrdf_load_stackoverflow) * 1978-07-07 1980-01-22
JP7029157B2 (ja) * 2017-10-03 2022-03-03 株式会社カワタ 粉粒体原料の供給装置

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3149760A (en) * 1960-12-23 1964-09-22 Xerox Corp Powder dispensing apparatus

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3149760A (en) * 1960-12-23 1964-09-22 Xerox Corp Powder dispensing apparatus

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4353485A (en) * 1979-02-15 1982-10-12 Aluminum Company Of America Apparatus for conveying particulate material by spring expansion and contraction
US5918539A (en) * 1998-05-14 1999-07-06 So.Ge. Ca. S.N.C. Device for making patterns or images having predetermined shape using powder substances
US20050276636A1 (en) * 2004-06-14 2005-12-15 Proweal Counter Corp. Magnetic roller for image developing means
US7194231B2 (en) * 2004-06-14 2007-03-20 Proweal Counter Corp. Magnetic roller for image developing means

Also Published As

Publication number Publication date
JPS5011538U (enrdf_load_stackoverflow) 1975-02-06
JPS5329151Y2 (enrdf_load_stackoverflow) 1978-07-21
DE2425368C3 (de) 1980-01-24
DE2425368A1 (de) 1975-01-02
DE2425368B2 (de) 1979-05-23

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