Ink pump

Abstract

 An ink pump (40) for a high speed mailing machine is disclosed. The ink pump 40 pumps ink from an ink reservoir 41 to an ink pad of an ink pad device 36. The ink pump 40 comprises a deformable chamber and valves (232, 234) which cooperate to pump ink upon compression of the chamber and release of the compression. The pump (40) comprises an input and an output, and the valves comprises a one way valve 232, e.g. a duck bill valve, disposed at the pump input which closes upon compression of the chamber and opens upon release of the compression, and a one way valve 234, e.g. a duck bill valve, disposed at the pump output which opens upon compression of the chamber and closes upon release of the compression. Duck bill valves (232, 234) enable the pump (40) to be disposed in any attitude including horizontal. These valves (232, 234) may be disposed entirely within the deformable chamber, which may comprise a sleeve 230 of elastic material.

Description

[0001] The invention disclosed herein relates generally to a pump, particularly to an ink pump for an ink pad device, which may be used to ink a printing device, particularly for a mailing machine.

[0002] In the mail processing field, it is highly desirable to imprint postage and other indicia on envelopes, packages, tapes, etc. at high speed. With such high speed operation, particularly where high volume is involved, it is important to maintain the quality of imprinted indicia.

[0003] In European Patent Application (EP-A) No. 321098 there is disclosed an inker module. The whole content of this disclosure is hereby incorporated in the present application.

[0004] A pump as disclosed herein comprises a deformable chamber and valving which cooperate to pump a fluid such as ink upon compression of the chamber and release of the compression. The pump is compact, economical to produce, capable of long service life and capable of high speed operation.

[0005] The pump may comprise an input and an output, and the valving may comprise a one way valve disposed at the pump input which closes upon compression of the chamber and opens upon release of the compression, and a one way valve disposed at the pump output which opens upon compression of the chamber and closes upon release of the compression.

[0006] In a specific embodiment, either or both of the one way valves comprise duck bill valves. Use of such valves simplifies construction of the pump, and where both one way valves are duck bill valves, the pump may be disposed in any attitude including horizontal, and the valves may be disposed entirely within the deformable chamber.

[0007] In a specific embodiment the deformable chamber comprises a sleeve of elastic material. The specific material used for the sleeve is non-reactive with the fluid to be pumped. In the case of ink, the sleeve may be made of neoprene, silicone rubber, polyethylene or polypropylene, depending on the particular ink to be pumped, as well as other elastic materials non-reactive to the particular ink to be pumped which are capable of being compressed and return to their original shape in a relatively short period of time.

[0008] In a specific embodiment, the pump comprises a first rigid tubular section having a flow path therethrough which forms the pump input. The sleeve is secured at one end thereof to the first tubular section. The pump comprises a second rigid tubular section having a flow path therethrough which forms the pump output, and the sleeve is secured at another end thereof to the second tubular member.

[0009] According to an embodiment of the invention, an ink pump and an ink pad device including an ink pad are attached so as to form a unit. Thus, the ink pad and the ink pump may be moved as a unit from the home position referred to above to the inking position referred to above when mounted to an ink device drive. Preferably, the ink pad/ink pump unit is a disposable unit.

[0010] Features of the apparatus as particularly disclosed and illustrated are: to provide an improved pump, particularly an ink pump for an ink pad device, usable, for example, to ink a printing device of a mailing machine;
to provide a pump, particularly an ink pump, which is compact and economical to produce;
to provide a pump, particularly an ink pump, which is serviceable over a large number of pumping cycles;
to provide a pump, particularly an ink pump, which is capable of high speed pumping operation;
to provide a pump, particularly an ink pump, which is disposable;
to provide a pump, particularly an ink pump, which may be operated in any attitude, including horizontally;
to provide an ink pump which is compact and may be incorporated into an ink pad device to pump ink from a reservoir to an ink pad of the ink pad device;
to provide an ink pump for ink pad devices which are capable of being replenished with ink from an ink reservoir; and
to provide an ink pump for pumping ink from an ink reservoir to an ink pad device in which the ink pad device is moved from a home position to an inking position tamped against a printing device wherein the ink pump is capable of being easily actuated in timed relation to movement of the ink pad device.

[0011] According to another embodiment, an ink pump and an ink reservoir are attached as a unit, preferably to be reused after the reservoir is emptied.

[0012] According to another embodiment of the invention, an ink pump, an ink pad device including an ink pad, and an ink reser­voir are attached so as to form a unit. Thus, the ink pad, the ink reservoir and the ink pump may be moved as a unit from the home position referred to above to the inking position referred to above when mounted to an ink device drive. Preferably, the ink pad/ink reservoir/ink pump unit is a disposable unit.

[0013] The invention is illustrated by way of example and not limitation in the figures of the accompanying drawings in which like references denote the same elements, and in which:

FIG. 1 is a front perspective view of a drive
for moving an ink pad tray from a home position to an inking position in a mailing machine;

FIG. 2 is a sectional view of the drive of FIG. 1, also showing the ink pad tray in its home position, and a pump for the ink pad, a printing device and a platen device in its home posi­tion;

FIG. 3 is a front prospective view of the drive depicted in FIG. 1;

FIG. 4 is a simplified side view partially broken away of the drive, ink pad, ink pad tray, platen device and printer device depicted in FIG. 3 with the ink pad tray and the platen device in their home positions;

FIGS. 5-7 are views similar to that of FIG. 4 showing the motion of the ink pad tray in stages from its rest position depicted in FIG. 4 to its inking position depicted in FIG. 7 with the ink pad tamped against the printing device, the platen device being shown in its home position;

FIG. 8 is a view similar to that of FIG. 4 showing the ink pad tray back in its home position and the platen device in its printing position tamping an envelope or tape against the printing device for imprinting the envelope;

FIG. 9 consisting of FIGS. 9a, 9b and 9c is a series of plots showing the relationship between the horizontal and verti­cal positions of the ink pad tray and the angle of the ink pad drive camshaft with respect to movement of the ink pad tray from its home to its inking position;

FIG. 10 consisting of FIGS. 10a, 10b, and 10C is a series of plots showing the relationship between the horizontal and vertical positions of the ink pad tray and the angle of the ink pad drive camshaft with respect to movement of the ink pad tray shortly before, during and shortly after tamping thereof against the printing device;

FIGS. 11-17 are stick diagrams illustrating the relative positions of drive linkages, the ink pump linkages and the drive camshaft and showing the percentage completed of the inking cycle in moving the ink tray from its home position to its inking posi­tion;

FIG. 18 is a perspective view of an ink pad, ink pad tray and pump;

FIG. 19 is an exploded perspective view of the ink pad, ink pad tray and pump depicted in FIG. 18;

FIG. 20 is a side sectional view of another embodiment of an ink pad, ink pad tray and pump, this embodiment including an ink reservoir, and this figure also showing portions of the ink tray drive which also actuate the pump; and

FIG. 21 is a sectional view of the reservoir and pump depicted in FIG. 20 taken along line 21-21 of FIG. 20.

[0014] Referring to FIGS. 1 and 2, inker module 25 includes a chassis 30 which houses drive 32 that (a) moves an ink pad tray 34 (FIG. 2) from a home position (FIG. 2) to an inking position (FIG. 7) in which an ink pad 36 (FIG. 2) is tamped against a printing device 38 (FIG. 2) to ink the printing device; and (b) actuates a pump 40 (FIG. 2) to pump ink from a reservoir 41 in ink pad tray 34 to ink pad 36. Chassis 30 also houses drive 42 which moves platen device 44 (FIG. 2) upwardly from a home posi­tion (FIG. 2) to a printing position (FIG. 8) in which an en­ velope or strip of tape 46 is pressed against printing device 38 to imprint postage indicia thereon. Printing device 38 is part of a flat-bed postage meter referenced generally by 47 (Fig. 2) which is pivotally mounted by a counterbalance mechanism 48 in a system including inker module 25.

[0015] Ink tray 34 at opposed sides 50 (FIG. 2) adjacent its rear 52 is pivotally connected to ends 54, 55 (FIG. 1) of links 56, 57, respectively, by inwardly projecting pins 59 from links 56, 57 snap fitted in receptacles 61 (FIG. 18) of ink tray 34. The forward part 63 of ink tray 34 is supported by pins 65, (FIG. 1) inwardly projecting from ends 67, 68 of links 70, 71, respectively. That snap-fit arrangement facilitates replacement of ink tray 34 as described in more detail below. Platform 72 is fixed to chassis 30 so that links 56 and 57 move relative to platform 72. Pins 65 extend into slots or cut-outs 73 in sides 50 of ink tray 34 (FIG. 18) so that ink tray 34 may be moved by links 56 and 57 relative to platform 72 riding on pins 65. Plat­form 72 is attached to opposed sides 73, 74 (FIG. 1) of chassis 30 by screws 75 so that it may be removed for ease of assembling, disassembling and servicing of drives 32 and 42. Links 70 and 71 are pivotally attached in a central region 77 thereof to platform 72 by pins 79 so that ends 67 and 68 of links 70 and 71 pivot up­wardly (clockwise) relative to platform 72. Movement of links 56 and 57 to the left in FIG. 1 move ink tray 34 horizontally to the left relative to platform 72, and clockwise pivoting of links 70 and 71 moves ink tray 34 vertically upwardly.

[0016] Drive 32 first moves links 56 and 57 to the left, as il­lustrated by the sequence of FIGS. 4-6, to move ink tray 34 horizontally to the left from its rest position (FIG. 4) to a position registered with printing device 38 (FIG. 6). Drive 32 then pivots links 70 and 71 (FIG. 7) to move ink tray 34 verti­cally and tamp it against printing device 38 to ink it. After drive 42 raises platen device 44 to press an envelope or tape strip 46 against printing device 38, drive 32 moves links 70 and 71, and links 56 and 57 move in reverse to the movements that brought ink tray 34 into its inking position, and return ink tray 34 to its home position.

[0017] Drive 32 (FIG. 3) includes drive motor 85, cam wheels 87, 88 fixed to camshaft 90 journaled to sides 72 and 73 of chassis 30, and pulley system 92 coupling motor shaft 93 and camshaft 90. Links 70 and 71 have respective rollers 94 rotatably connected to respective ends 96 thereof and are supported from chassis sides 72 and 73 such that respective rollers 94 ride on cam wheels 87 and 88, respectively. Springs 95 urge links 72 and 73 towards cam wheels 87, 88, and urge rollers 94 thereof into engagement with cam wheels 87, 88. Links 56 and 57 are pivotally connected at respective ends 100 thereof to respective ends 102 of links 104 and 105, respectively. Links 104 and 105 are pivotally con­ nected at respective ends 107 to chassis sides 73 and 74, respec­tively, and have respective rollers 109 rotatably connected to a respective central part 110 thereof. Links 56 and 57 have rotatably connected to a respective central part 111 (FIG. 2) thereof respective rollers 112. Springs 113 urge links 56 and 57 towards cam wheels 87, 88, and urge rollers 112 thereof into engagement with cam wheels 87, 88. Cam wheels 87 and 88 each in­clude a cam surface 114 on which a respective roller 94 rides, a cam surface 115 on which a respective roller 109 rides, and a cam surface 116 on which a respective roller 112 rides. Links 56 and 104, and links 57 and 105 are interconnected and supported such that respective rollers ride on respective cam surfaces of cam wheels 87 and 88, respectively, as respective cam followers. The cam surfaces are contoured to move the various links upon a given rotation of camshaft 90 to provide the motion of ink tray 34 de­scribed above and defined by Fig. 9, and the cam surfaces are aligned axially offset, as shown, or may be circumferentially aligned along the respective outer peripheries of cam wheels 87, 88. Cam wheels 87, 88 may be rotated through a cycle, with con­stant velocity or continuously with variable velocity, or cam wheels 87, 88 may be oscillated through a cycle.

[0018] Referring to FIGS. 1-3, drive 42 includes motor 118 hav­ing motor shaft 119, supported from sides 73, 74 of chassis 30 by bearing 120 (FIG. 3), gear 122 fixed to shaft 119, gear 123 mesh­ ing with and driven by gear 119, shaft 124 fixed to gear 123 and supported from chassis 30 by bearings 125, pinion gears 126 fixed to shaft 124, and racks 127 (FIG. 2) fixed to opposed sides of platten device 44 meshed with respective pinion gears 126. Ac­tuation of motor 118 causes pinion gears 126 to rotate, engaging and elevating respective racks 127 and with them platten device 44. FIGS. 4-8 show elevation of platten device 44 with respect to movement of ink pad tray 34.

[0019] In order to produce straight line (e.g. generally horizontal) and parallel motion (e.g., parallel to the indicia surface of printing device 38), links 57 must experience some orthogonal motion (e.g., generally vertical). Links 105 and the corresponding cam surfaces cooperate with links 57 to provide that motion. Additionally, links 105 and the corresponding cam surfaces provide the orthogonal (vertical) motion during tamping.

[0020] The relationship between ink tray movement and camshaft 90 rotation is given in FIG. 9. FIG. 9(a) shows horizontal ink tray movement versus time; FIG. 9(b) shows vertical ink tray movement versus time; and FIG. 9(c) shows camshaft angle rotation versus time. The ordinate axes time scales in FIGS. 9 (a), (b) and (c) are identical, so that viewing FIG. 9(a) and/or FIG. 9(b) with FIG. 9(c) gives horizontal and/or vertical displacement versus camshaft angle.

[0021] The plots in FIGS. 10(a), (b), and (c) are similar to the corresponding plots in FIG. 9 and give the relationship between ink pad tray movement and camshaft angle on an expanded side shortly before, during and shortly after the ink tray is tamped against the printing device, and include additional information. The cam profiles are configured to ensure that there is a bounce­less strike of ink pad 36 against printing device 38, i.e., once ink pad 36 has been tamped against printing device 38 and it starts its downward movement, it is prevented from restriking printing device 38. FIG. 10 also gives ranges for acceptable ink tray vertical heights and indicia heights. The cam profiles are further configured to provide smooth acceleration and decelera­tion.

[0022] As mentioned above, drive 32 also actuates a pump 40 which pumps ink from reservoir 41 to ink pad 36. Referring to FIG. 2, link 130 is pivotally supported in its central part 132 from bracket 134 of chassis 30 with link end 136 adjacent cam wheel 88 and link end 138 adjacent pump 40. Roller 140 is rotatably connected to end 136 of link 130, and link 130 is con­figured and supported so that roller 140 rides on cam surface 142 as a cam follower. Rotation of cam wheel 88 pivots link 130 so that end 138 compresses pump 40 to create a pumping action there­in as described below. Pump 40 is compressed once for each tamp­ing of ink pad 36 against printing device 38, or less than once or more than once depending upon the amount of ink required. In the disclosed embodiment, pump 40 is compressed once for each ink pad tamping. It is preferred that pump 40 be compressed starting shortly before and during a substantial portion of the time that ink pad 36 is tamped against printing device 38. At high speed operation, it is preferred to pump only once per inking cycle to allow enough time for the pump material to relax to its original shape before compressing it again.

[0023] FIGS. 11-17 show the relative positions of links 57, 71, 105 and 130, rollers 96, 109, 112 and 140, cam wheel 88, ink tray 34, printing device 38, platen device 44 and pump 40 for dif­ferent times of the inking cycle indicated in each figure as a percentage of the inking cycle. FIG. 11 shows the various parts in the home position of ink tray 34 (100% or 0% of the cycle), and FIG. 17 shows the various parts at the inking position of ink tray 34 when ink tray 34 is at its maximum height (about 30% of the cycle) and tamped against printing device 38. A time is in­dicated on each figure corresponding to times on the ordinate axis in FIGS. 9 and 10. A Cartesian coordinate system is referenced in the upper part of FIGS. 11-17 with the ordinate axis 175 representing the horizontal or "x" position of ink tray 34 and the coordinate axis 179 representing the vertical or "y" position of ink tray 34, with the origin of the coordinate system designated 183. The links and rollers (followers) are designated in FIG. 11 with respect to the axis along which they control movement. Diametric line 90 through the circle representing cam wheel 88 and diametric line 93 through the circle representing shaft 93 of motor 85 indicate in FIGS. 11-17 rotational rela­tionship of cam wheel 88 and motor shaft 93 and the positional relationship of the various links and rollers at the indicated times in the cycle. Ink pad 36 also moves along the x-axis at the same time it is rising at the last .060 inch of vertical rise (total rise is .210) to provide a wiping action against the printing drive, which improves ink transfer. This is referred to in the drawings as "alpha-scrub". The alphascrub ratio is 4:1, that is; .015 inch x-motion for the .060 inch y-motion. Various references locations are represented by cross hatches.

[0024] Referring to FIGS. 18 and 19, ink cartridge 200 includes ink reservoir 41 and ink tray 34 which holds ink pad 36 in an ink distribution chamber 204. Ink pad 36 is made of a resilient sor­bent material which sorbs (i.e., absorbs) ink contained in ink distribution chamber 204. Ink pad 36 is compressed slightly dur­ing tamping thereof against inking device 38 to transfer ink thereto. Releasing of compression causes additional ink to be sorbed to the upper portion of ink pad 36. Preferably, ink pad 36 also sorbs ink through capillary action.

[0025] For use in a high speed mailing machine environment, ink tray 34 is constructed to transfer up to ink four times or more per second to the printing device 38, which imposes restraints on the amount of time in which ink must be sorbed by ink pad 36 and the amount of time in which ink must be transferred to printing device 38. Referring to FIGS. 9 and 10, each inking cycle is about 0.25 seconds (250 ms) including rest time, and is about 160 ms excluding rest time. Tamping takes up about 25 ms. There­fore, ink release to printing device 38 must take place within 25 ms, and a resupply of ink must be sorbed to the upper part of ink pad 36 in about 225 ms. Pump 40 must be compressed in about 80 ms and recover in about 80 ms. The design of ink tray 34 and pump 40 disclosed herein takes those restraints into considera­tion.

[0026] Ink pad 36 disclosed herein (FIGS. 18 and 19) includes a single layer or multi-layers. In the disclosed embodiment, two layers are shown, upper layer 36a and lower layer 36b. Upper layer 36a functions as a metering layer to release a metered amount of ink during tamping thereof against printing device 38, and lower layer 36b functions as a supply layer to the upper metering layer 36a to replenish ink released by the upper layer. Typically, upper layer 36a has a smaller average pore diameter than lower layer 36b, and ink transfer from ink distribution chamber 204 to lower layer 36b, and from lower layer 36b to upper layer 36a is by capillary action and negative internal pad pres­sures. During tamping, upper layer 36a is compressed slightly so that some ink transfer also occurs from lower layer 36b to upper layer 36a as a result, and upon release, of compression of upper layer 36a. The particular material used for ink pad 36 may depend upon the particular ink used. For example, when a disper­sion ink is used, upper layer 36a and lower layer 36b may be a Scotfelt foam laminate (polyurethane) which consists of a firm­ness of 20 (upper) over 8 (lower), and when a solution ink is used, upper layer 36a may be in the so-called "Porex" media (sintered polyethylene), i.e., a polyethylene laminated with a heat-activated adhesive extending in a spider web pattern, and lower layer 36b may be an olefinic material such as Neoprene.

[0027] Referring to FIGS. 18 and 19, ink distribution chamber 204 has an inlet 206, an optional outlet 208, a number of chan­nels 210 formed therein by partitions 212 and a manifold 214 in communication with partitions 210. Ink pad 36 is supported on partitions 212 in communication with channels 210 and manifold 214 so as to sorb ink present in channels 210 and manifold 214. The height of partitions 212 is selected to properly deliver the required amount of ink at highest possible usage while printing. For the specific ink used in the mailing machine referred to above, the height is about .030 inch.

[0028] Although channels 210 are shown to extend parallel to each other and to be of equal size, they need not be, and other designs may be suitable for supplying ink to ink pad 36.

[0029] Tubing 216 represented schematically in FIG. 18 communi­cates the output 218 of pump 40 with the inlet 206 of ink distri­ bution chamber 204. In some applications it is preferable to provide for the removal of excess ink to avoid overflow and splashing during high speed operation, and to insure adequate ink supply. Ink usage is variable depending on the printing area (with or without ad slogan; variation in the ad slogan design, etc.). For use of ink tray 34 in such applications, ink distri­bution chamber 204 may optionally have an outlet 208, and reser­voir 41 may have an inlet 220. Ink distribution chamber outlet 208 and reservoir inlet 220 are communicated via tubing 222 (represented schematically), or may be blocked, depending on the particular application, etc. Reservoir 41 has an outlet (not shown in FIGS. 18 and 19) within support 226 in direct communica­tion, without valving, etc., with the input 224 of pump 40.

[0030] Ink flow is as follows. Pump 40 injects ink into ink distribution chamber 204 from reservoir 41 via pump output 218, tubing 216 and ink distribution chamber inlet 206. Optionally, excess ink in ink distribution chamber 204 not sorbed by ink pad 36 is returned to reservoir 41 via ink distribution chamber out­let 208, tubing 222 and reservoir inlet 220. Outlet 208 is com­municated with ink distribution chamber 204 at an appropriate height so that excess ink flows back to reservoir 41 primarily by gravity force and to some extent by the pumping action of pump 40. If desired, a second pump (not shown) may be used to pump excess ink back to reservoir 41.

[0031] Pump 40 (FIG. 21) comprises an elastic sleeve or tube 230 capable of repeatedly being compressed and recovering to its original shape. Within sleeve 230 are disposed an input valve 232 and an output valve 234. Valves 232 and 234 are one-way valves which permit liquid to flow from the reservoir (41 in FIG. 18) into sleeve 230, and from sleeve 230 into ink pad distribu­tion chamber 204. Ink reservoir 41 (FIGS. 18 and 19) includes a bearing surface 235 against which sleeve 230 is compressed by end 138 of link 130 (FIG. 2). Compression of sleeve 230 by link 130 closes valve 232 and opens valve 234, and expels ink from sleeve 230 through open valve 234. Upon release of the compression, a partial vacuum is created within sleeve 230 which closes valve 234 and opens valve 232, and which draws additional ink into sleeve 230. Valves 234 and 232 operate in the nature of ball valves, but are disposed entirely within sleeve 230. In the preferred embodiment valves 232 and 234 are duck bill valves which not only allow valves 232 and 234 to be placed entirely within sleeve 230, but also permit pump 40 to be operated at any attitude. In the embodiments illustrated in the drawings, pump 40 is disposed horizontally. In the presently preferred embodi­ment, the diameter of sleeve 230 is about 5/8 inch and its length about 2 inches, and is compressed by about 1/8 inch.

[0032] The particular application in which pump 40 will be used requires a consideration of the fluid to be pumped, the nature of the service environment, service life, cost, serviceability, etc. In the specific embodiments disclosed herein, sleeve 230 is made of an elastic material which is (a) non-reactive with the partic­ular ink being used, (b) can withstand repeated compression cycles in the thousands to millions and recover to substantially its original shape to thereby perform the pumping action de­scribed above over the desired service life of the pump, and (c) can recover to substantially its original shape in a fraction of a second, more specifically within a time permitting at least four full pumping cycles per second. The wall thickness of sleeve 230 has an effect on service life and recovery time. A thicker wall thickness provides a faster recovery time, but also subjects sleeve 230 to more stress which reduces service life. For example, sleeve 40 may be made of an olefinic material such as Neoprene, silicone rubber, polyethylene or polypropylene which may have a preferred wall thickness of about 1/16 inch, and the duck bill valves may be made of olefinic material such as Neoprene (for ink capability). Similarly, other parts which come into contact with ink are made of a material which is not reac­tive with the particular ink used. Sleeve 230 may be connected to reservoir 41 by fitting the ends thereof tightly over conical fittings 236, 238 (FIG. 21), and sealing the sleeve to the fit­tings by means of an adhesive, heat shrinking, etc.

[0033] Referring to FIGS. 18 and 19, ink cartridge 200 (includ­ing ink tray 34) and ink pump 40 may be supplied as a disposable cartridge unit comprising ink reservoir 41, ink pad holder 202 including ink distribution chamber 204 and ink pad 36, and pump 40. Such a cartridge may be supplied tightly covered in foil or plastic to preserve product integrity during shipment, storage and handling, and ready for installation, which is facilitated by virtue of the snap-fit construction of ink tray 34 described above. Ink cartridge 200 includes a finger grasp 240 which may be engaged to un-snap ink cartridge 200 from and snap ink cartridge 200 into inker module 25. If desired individual parts of ink tray 34 and ink cartridge 200 may be replaced, although replacement as a unit is preferred.

[0034] FIGS. 20 and 21 depict an alternate embodiment in which ink cartridge 200 includes ink tray 34A, and ink pad holder 202A including ink distribution chamber 204A. Ink cartridge 200 does not include an ink reservoir, rather a separate larger reservoir 250 is provided. Ink pad holder 202A is constructed and mounted similar to ink pad holder 202, and ink distribution chamber 204A is similar to ink distribution chamber 204. Platform 72A is con­structed and mounted similar to platform 72 except that reservoir 250 is disposed transversely to the plane of platform 72A, i.e., vertically, protruding through hole 252 thereof. Ink pad holder 202A moves relative to platform 72A as generally described for ink tray 34 and platform 72. Ink reservoir 250 is received in receptacle 254 mounted to the bottom 256 of chassis 30A by flanges 257. With tray 34A removed, reservoir 250 is simply dropped in or lifted out of receptacle 254. Pump 40 is affixed to the bottom 260 of reservoir 250 projecting through hole 261 of receptacle 254. Pump 40 extends horizontally as in the embodi­ment of FIGS. 18 and 19.

[0035] Drive 32A includes a link 130A supported to be cammed by cam wheel 87A similar to link 130 and cam wheel 87 so that its end 138A compresses sleeve 230 of pump 40, as described above for drive 32, link 130 and cam wheel 87. The output of pump 40 is communicated with the inlet 206A of ink distribution chamber 204A by tubing 216A, and the outlet of ink distribution chamber 204A is communicated with port 262 of reservoir 250 by tubing 222A. Port 262 communicates with the input 224 of pump 40.

[0036] Ink tray 34A and reservoir 250 and pump 40 operate to pump ink from reservoir 250 to ink distribution chamber 204A as described for the embodiment depicted in FIGS. 18 and 19, except that excess from ink distribution chamber 204A tends to be recir­culated rather than returned to reservoir 250.

[0037] In the embodiment depicted in FIGS. 20 and 21, ink reser­voir 250 and pump 40 are replaceable separately from ink tray 34A. Tray 34A may easily be replaced, as described for tray 34, by a new tray., After un-snapping tray 34A, and disconnecting tubing 216A and 222A, reservoir 250 is exposed and may easily be lifted out of receptacle 254 for removal and replacement, and thereafter replaced by connecting tubing 216A and 222A, and dropping reservoir 250 back into receptacle 254. If necessary, receptacle 254, reservoir 250 and pump 40 may be replaced by a new unit.

[0038] For those embodiments which include an ink pump 40, it may be necessary to initialize the system each time an ink tray is changed to pump a predetermined amount of ink into the ink distribution chamber 204, 204A before commencing actual printing operations.

[0039] The control system described in U.S. application Serial No. 291483, (Case C.444), may be used to accomplish and synchronize the foregoing operation of drives 32 (32A) and 42, and pump 40.

[0040] Changes and modifications of the embodiments of the invention herein disclosed will be readily apparent to those skilled in the art. Moreover, uses of the invention other than in mailing apparatus will also be readily apparent to those skilled in the art. Changes and modifications may therefore be made to the embodiments of the invention herein described without departing from the invention.

Claims

1. A pump comprising a deformable chamber, an input, an output, a one way valve disposed at said pump input which closes upon compression of said chamber and opens upon release of said compression, and a one way valve disposed at said pump output which opens upon compression of said chamber and closes upon release of said compression.

2. The combination of an ink pad device and an ink pump, said ink pad device including an ink pad, said combination including means connecting said ink pad and said pump for pumping ink to said ink pad.

3. A mailing machine including an ink reservoir and a pump in combination, said combination including means connecting said ink reservoir and said pump for pumping ink from said reservoir to an ink pad.

4. A pump according to claim 1 wherein said valves are disposed entirely within said deformable chamber.

5. A pump according to claim 1 or 4 wherein either or both of said one way valves comprise duck bill valves.

6. A pump according to claim 1, 4 or 5 wherein said deformable chamber comprises a sleeve of elastic material.

7. A pump according to claim 6 wherein said sleeve is made of a material selected from the group consisting of neoprene, silicone rubber, polyethylene and polypropylene.

8. A pump according to claim 6 or 7 comprising a first rigid tubular section having a flow path therethrough and forming said pump input, said sleeve being secured at one end thereof to said first tubular section, said pump comprising a second rigid tubular section having a flow path therethrough and forming said pump output, said sleeve being secured at another end thereof to said second tubular member.

9. The combination of claim 2 wherein said ink pump and said ink pad device are attached so as to form a unit which is optionally disposable.

10. The combination according to claim 2 or 9 wherein said unit includes means for mounting said unit to a drive for moving said unit from a home position to an inking position in which said ink pad of said unit is tamped against a printing device.

11. The combination of claim 10 wherein said pump comprises a deformable chamber and valving which cooperate to pump ink upon compression of said chamber and release of said compression, said pump being mounted in said unit to be accessible to receiving an actuating member of said drive to compress said chamber in timed relation to movement of said unit to said inking position.

12. A machine according to claim 3 wherein said ink reservoir is integral with said ink pad device.

13. A machine according to claim 12 wherein said unit includes means for mounting said unit to a drive for moving said unit from a home position to an inking position in which said ink pad of said unit is tamped against a printing device.

14. A machine according to claim 13 wherein said pump comprises a deformable chamber and valving which cooperate to pump ink upon compression of said chamber and release of said compression, said pump being mounted in said unit to be accessible to receiving an actuating member of said drive to compress said chamber in timed relation to movement of said unit to said inking position.

Drawing