Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41J—TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
  • B41J2/00—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed
  • B41J2/005—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by bringing liquid or particles selectively into contact with a printing material
  • B41J2/01—Ink jet
  • B41J2/135—Nozzles
  • B41J2/14—Structure thereof only for on-demand ink jet heads
  • B41J2/14201—Structure of print heads with piezoelectric elements
  • B41J2/14282—Structure of print heads with piezoelectric elements of cantilever type
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
  • B05B—SPRAYING APPARATUS; ATOMISING APPARATUS; NOZZLES
  • B05B12/00—Arrangements for controlling delivery; Arrangements for controlling the spray area
  • B05B12/02—Arrangements for controlling delivery; Arrangements for controlling the spray area for controlling time, or sequence, of delivery
  • B05B12/06—Arrangements for controlling delivery; Arrangements for controlling the spray area for controlling time, or sequence, of delivery for effecting pulsating flow
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41J—TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
  • B41J2/00—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed
  • B41J2/005—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by bringing liquid or particles selectively into contact with a printing material
  • B41J2/01—Ink jet
  • B41J2/015—Ink jet characterised by the jet generation process
  • B41J2/04—Ink jet characterised by the jet generation process generating single droplets or particles on demand
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41J—TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
  • B41J2202/00—Embodiments of or processes related to ink-jet or thermal heads
  • B41J2202/01—Embodiments of or processes related to ink-jet heads
  • B41J2202/05—Heads having a valve

Definitions

• This invention relates to a fluid applicator, that is to say a device for applying a fluid to a body, e.g. of paper or cardboard.
• a fluid applicator that is to say a device for applying a fluid to a body, e.g. of paper or cardboard.
• the preferred embodiment of the invention is particularly suitable for the application of liquid adhesive materials, although the invention is not limited to this use.
• a fluid applicator comprising a fluid reservoir; an outlet passage leading from the fluid reservoir to a nozzle; a closure member normally closing the outlet passage but reciprocable within the reservoir in a direction generally parallel to the axis of the passage to repeatedly open and close the passage, each passage closure resulting in a small volume of fluid from the reservoir being forced by the closure member into the passage to eject a corresponding volume of fluid from the nozzle.
• the preferred embodiment of fluid applicator when used to apply adhesive material has the advantage that it can be controlled with g ⁇ eat precision enabling the flow of adhesive to be turned “on” and “off” in a precisely defined manner, thereby enabling adhesive areas to be set down with considerable precision.
• the preferred fluid applicator is particularly suitable for electronic control thereby enabling the size, shape, and position of adhesive patterns to be controlled easily by use of a computer. This is of particular advantage since details of a particular adhesive pattern may be readily set up in the computer, and stored for future production runs requiring the same pattern.
• Figure 1 is a schematic cross-section of one embodiment of the invention.
• Figure 2 is a schematic cross-section of a second embodiment of the invention.
• the fluid applicator shown in Figure 1 comprises a body 2 defining a fluid reservoir 3 to which fluid is supplied via an inlet 4.
• the fluid will typi ⁇ cally be an adhesive, and is supplied to the inlet 4 under pressure to maintain a predetermined pressure within the reservoir 3 •
• An outlet passage 5 leads from the reservoir 3 to a nozzle 6.
• the end of the passage 5 nearest the reservoir 3 is conical and forms a seat 7 for a closure member 8 which is normally biased into engagement with the seat 7 to close the outlet passage to fluid flow.
• the closure member 8 is mounted on an actuating mechanism 9 which can be controlled by electrical signals supplied to wires 10 connected to the actuating mechanism 9- By supplying appropriate control signals via the wires 10 the actuating mechanism 9 can operate to move the closure member 8 upwardly as illustrated in the drawing, i.e. in the axial direction of the passage 5 - When the closure member is so moved fluid within the reservoir 3 fills the conical upper end of the passage. When the closure member is subsequently rapidly returned to the position illustrated in the drawing a small volume of fluid is forced along the passage 5 causing a corresponding volume of fluid to be ejected from the nozzle 6.
• the closure member 8 is reciprocated rapidly to eject a series of dots or droplets of fluid rom the nozzle 6.
• the closure member 8 is reciprocated at a frequency of 1000 Hz to produce a corresponding stream of dots of fluid at a rate of 1000 dots per second.
• the size of the dots may be adjusted by adjusting the size of orifice 6 and/or the pressure of fluid within the reservoir 3, and the frequency at which dots are emitted may be adjusted by varying the frequency of reciprocation of the closure member 8.
• the rate of fluid ejected in terms of volume per unit time may be varied over a wide range in accordance with the nature of the fluid to be applied and the nature and speed of movement of the web to which the fluid is applied.
• a typical use of the applicator 1 is to apply adhesive to a moving web of material, for example a moving web of paper in a business forms production machine, packaging machinery, or paper conversion machinery.
• a moving web of material for example a moving web of paper in a business forms production machine, packaging machinery, or paper conversion machinery.
• the appli ⁇ cator will, when ejecting fluid, produce on the moving web a line of dots.
• the diameter of the dots will be deter ⁇ mined by the physical parameters of the applicator and the fluid being ejected, and the position of the dots relative to each other will be determined by a combination of the frequency of reciprocation of the closure member 8 and the speed of movement of the web. For a given web speed the frequency of reciprocation will be selected to give the desired dot spacing. It may be desirable for the individual dots to overlap so that whilst the applicator is actuated a continuous line of adhesive is produced, or it may be desirable to have discrete dots, depending on the circum ⁇ stances .
• the applicator can readily be turned on and off under electrical or electronic control.
• the individual actuating mechanisms 9 can be controlled separately to produce any desired adhesive pattern on the moving web.
• chevron shaped bars of adhesive or wavey lines of adhesive can be produced in any orientation relative to the direction of movement of the web by suitable control of the actuating mechanisms.
• control is preferably effected electronically under program control.
• a computer may be used to set up a particular pattern of adhesive on a screen and the pattern so set up may automatically be reproduced by the applicators under program control.
• One typical use of the present invention is in the formation of continuous business forms which may consist of several webs of paper secured together by lines of adhesive along the laterial edges of the webs.
• Applicators as described above may be used to apply continuous lines of adhesive along the laterial edges of the webs, or broken lines or even a series of individual dots. Further, suitable banks of applicators arranged across the direction of the web may be used to lay down lines of adhesive transverse to the web direction for example to connect together the top edge of a set of business forms, or to form sealed envelopes consisting of two or more webs of material united together along four sides.
• applicators described above are potentially of value in the packaging industry, e.g. in the formation of cartons, and in the paper conversion industry.
• each body 2 houses a number of passages 5 and corresponding closure members 8 to produce an applicator unit which can lay down a number of overlapping lines of adhesive. A single such unit may be used to span the full width of a web of material or several such units may be assembled together to form a complete fluid applying machine.
• the actuating mechanism 9 may be of. any suitable type able to reciprocate the closure member in the manner required.
• a piezo- ceramic actuator is used.
• FIG. 2 The embodiment shown in Figure 2 is similar to that of Figure 1 in that it comprises a body 2 defining a reser ⁇ voir 3 to which fluid is supplied via an inlet 4 and from ⁇ vhich fluid is ejected into an outlet passage 5 by recip- rocation of a closure member 8A.
• a body 2 defining a reser ⁇ voir 3 to which fluid is supplied via an inlet 4 and from ⁇ vhich fluid is ejected into an outlet passage 5 by recip- rocation of a closure member 8A.
• the closure member 8A is mounted on a tensioned wire 11 which passes through insulating bushes 12,13 and to the free ends 14,15 of which are connected the control wires 10 of the associated control equipment.
• the closure member 8A is mounted in a magnetic field the lines of force of which run perpendicular to the plane of the paper so that when a suitable A.C. current is fed through the wire 11 the closure member is reciprocated by a magneto- galvanic effect.
• Any other suitable system for reciprocating the closure member may be adopted, for example a high speed solenoid system.
• the exact nature of the mechanism for reciprocating the closure member is not critical and any arrangement which can reciprocate the closure member at the desired frequency and which is susceptible to electrical or electronic control may be used.
• the shape of the passage and the closure member may be different from that illustrated. It has been found that various combinations of passage shape and closure member shape give satisfactory results, and any combination of shapes which results in the ejection of a droplet of fluid from the nozzle each time the closure member is reciprocated may be used. It should be understood that the invention operates by positively ejecting a stream of droplets from the nozzle rather than simply opening and closing a valve at the outlet of a pressurized vessel of fluid, and any combination of passage and closure member which provides the required positive ejection of droplets of fluid is within the scope of the invention.
• the frequency of reciprocation of the closure member and the speed of movement of the web will be stich that the dots of fluid, when they hit the web, will spread out to overlap each other so that when the applicator is "on" a continuous line of fluid is laid down on the web
• the speed of movement of the web may be such that the dots do not overlap, and accordingly a line of dots is laid down when the applicator is "on”.
• the applicator may be such that the closure member can be held in the open position, thereby enabling a con ⁇ tinuous stream of fluid to flow from the applicator.
• a plurality of applicators are associated with a microcomputer control unit which auto- matically turns each applicator on and off under program - ⁇ -
• the applicators may be arranged in a single row across the web, or in a plurality of mutually offset rows. If offset rows are used, the control unit preferably automa-tically compensates for the offset when turning the applicators on and off.
• the control unit may incorporate a screen to enable an application pattern to be set up and dimensionally verified for size and position using only the control unit. Additionally or alternatively the control unit may accept programming from another computer either by direct connection (temporary or permanent) or by use of some machine readable transfer medium e.g. a magnetic disc or tape.
• the fluid applied may be a liquid or- a flowable powder, and may be other than an adhesive.
• a specific example of an alternative use of the applicator is the application of liquid ink in a desired pattern, e.g. to print information such as packaging data on cardboard cartons.

Landscapes

• Coating Apparatus (AREA)
• Application Of Or Painting With Fluid Materials (AREA)

Priority Applications (3)

Applications Claiming Priority (2)

Publications (1)

Family

ID=10576589

Family Applications (1)

Country Status (6)

Cited By (45)

Families Citing this family (1)

Citations (5)

• 1985
  • 1985-03-25 GB GB858507688A patent/GB8507688D0/en active Pending
• 1986
  • 1986-03-25 EP EP19860901966 patent/EP0215884A1/en not_active Withdrawn
  • 1986-03-25 JP JP50195086A patent/JPS63500156A/ja active Pending
  • 1986-03-25 WO PCT/GB1986/000173 patent/WO1986005722A1/en not_active Application Discontinuation
  • 1986-03-25 ES ES553418A patent/ES8703299A1/es not_active Expired
  • 1986-11-24 FI FI864770A patent/FI864770A/fi not_active IP Right Cessation

Patent Citations (5)

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