US3804400A

US3804400A - X-ray film feed method and apparatus

Info

Publication number: US3804400A
Application number: US00235052A
Authority: US
Inventors: R Hunt; M Hura
Original assignee: Picker Corp
Current assignee: Philips Nuclear Medicine Inc
Priority date: 1972-03-16
Filing date: 1972-03-16
Publication date: 1974-04-16
Anticipated expiration: 1991-04-16

Abstract

An X-ray film feeder for sequentially feeding sheets from a stack of film sheets of cut X-ray film into film processor. A primary feed roll is disposed above the film stack. The top sheets of film are fed one at a time between the primary feed roll and a stripper bar. Secondary feed rolls serve to downwardly deflect portions of the film sheets which have passed between the primary feed roll and the stripper bar to bias a sheet being fed away from the stripper bar to prevent scratching of the film by the stripper bar.

Description

United States Patent 1191 11] 3,804,400 Hunt et a]. Apr. 16, 1974 X-RAY FILM FEED METHOD AND l.5l5,986 11/1924 Wright et a] 271/41 APPARATUS 2,670,954 3/1954 Bach 271/37 x 3,047,290 7/1962 Thomsen 27l/36 [75] Inventors: Rober E H n South Euclld; 3,265,383 8/1966 Shute 271/24 x Michael Hui-a, Wickliffe, both of Ohio Primary Examiner-Evon C. Blunk 73 Assi nee: Picker Cor ration Cleveland, Assistant Examiner Bruce Stone 1 8 Ohio p0 Attorney, Agent, or Firm-Watts, Hoffmann, Fisher &

Heinke [22] Filed: Mar. 16, 1972 [21] Appl. No.: 235,052 [57] ABSTRACT 1 An X-ray film feeder for sequentially feeding sheets 52 US. Cl 271/10, 271/118, 271/121 a stack of film Sheets cut Y film into film 51 1m. (:1 B65h 3/06 processor- A Primary feed is disposed above the [58] Field of Search u 27 V36, 37, 38, 39, 4O film stack. The top sheets of film are fed one at a time 271/10, 41 between the primary feed roll and a stripper bar. Secondary feed rolls serve to downwardly deflect portions [56] References Cited of the film sheets which have passed between the pri- UNITED STATES PATENTS mary feed roll and the stripper bar to bias a sheet being fed away from the stripper bar to prevent 275/7333); scratching of the film by the stripper ban 3:260:52l 7/1966 Moxness 271/39 22 Claims, 9 Drawing Figures riammo PATENTEU AFR $6 i974 SHEET 3 UP 3 CROSS-REFERENCE TO RELATED PATENT FILM PROCESSOR, US. Pat. No. 3,4l8,9l3 issued Dec. 31, 1968 to J. L. Snarr.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to X-ray film processors and more specifically to a processor equipped with an automatic film feeder for sequentially feeding sheets of X-ray film into the processor. I

2. Prior Art In the past there have been a number of proposed mechanisms for feeding sheets of X-ray film into a film processor. By way of example, the referenced patent teaches an X-ray film feeder which will accommodate a stack of cut film sheets of admixed sizes and sequentially feed the sheets with controlled spacing into a developer region of a film processor.

The processor of the referenced patent has astripper bar positioned adjacent a feed roll in order to separate or strip the sheets of film positioned in a tray, and to assure that onlyone sheet at a time is fed from the tray and into the film processor. The stripper bar has been positioned at a spacing from the feed roll which is sufficient to permit one but only one sheet of film to pass at a time. One problem commonly encountered with such known film feeder mechanisms is that the film sheets tend to drag across the stripper bar whereby some scratching of the sheets occasionally results. Another problem is that the tray remains elevated until the feeding ofa sheet of film is sensed, and during the time of tray elevation the pressure of the tray causes the leading edge of the feeding film to be scratched either by the tray or by a burred edge of an adjacent film in the stack.

SUMMARY OF THE'INVENTION The present invention provides a mechanism for sequentially feeding X-ray film sheets into the developing region of a film processor with minimal scratching.

A film feeder is provided including a primary feed roll positioned above the film stack. Top sheets of film from the stack are sequentially fed between the primary feed roll and a stripper bar. In order to prevent the film sheets from dragging on the stripper bar, secondary feed rolls are provided to downwardly deflect those film portions which have passed between the pri-- mary feed roll and the stripper bar. By this arrangement, the film is flexed such that trailing film sheet portions are biased upwardly away from the stripper bar and into engagement with the primary feed roll.

In order to minimize scratching of leading portions of a film sheet being fed due to tray pressure against the feed roll, the tray is held upwardly for only a brief timed interval which is sufficeint to initiate feeding of the top sheet of film from the stack. Small adjustable idler rollers are provided to maintain the leading portion of the film in contact with the feed roll to continue feeding the leading portion of the film until it is engaged by the secondary feed rolls. The secondary feed rolls then flex the film to assure that trailing film sheet portions do not drag on the stripper bar as the film .is fed through the feeder and into the processor.

Accordingly, it is the primary object of the present invention to provide an improved film feed mechanism for feeding sheets of X-ray film into a film processor.

Other objects and a fuller understanding of the invention may be had by referring to the following description and claims taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an elevational view partially in cross section of a film processor including the novel film feed mechanism of the present invention;

FIG. 2 is an enlarged elevational view of the film feed mechanism with portions broken away to illustrate detail;

FIG. 3 is a sectional elevational view showing in greater detail the structural arrangement of the feed mechanism;

FIG. 4 is a plan view partially in cross section as seen from the plane indicated by the line 44 in FIG. 2;

FIG. 5 is an end view of the stripper bar of the feed mechanism;

FIG. 6 is a sectional end view of the feeder mechanism as seen from the plane indicated by the line 6-6 in FIG. 2;

FIG. 7 is a sectional end view of the feed mechanism as seen from the plane indicated by the line 7-7 in FIG. 2;

FIG. 8 is an elevational view as seen from the plane indicated by the line 8-8 in FIG. 7; and,

FIG. 9 is a schematic electrical circuit diagram of the timer control circuit which holds the film tray in an elevated position for a brief controlled time interval to initiate film feeding.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG. I, a film processor is shown generally at 10. The film processor 10 includes a main housing 11 within which are disposed developing, fixing, and'wash tanks 12, l3, 14. A feed assembly housing 15 is supported from the main housing 11 and extends laterally to the left as viewed in FIG. I.

The main housing 11 is ordinarily positioned outside of a darkroom, while the feed assembly housing I5 is positioned within a darkroom. An apertured darkroom wall is shown in phantom at 16. A laterally projecting flange 17 circumscribes the edges of an aperture in the wall 16 forming a light-tight seal.

A film feed assembly 20 is removably supported within the feed assembly housing 15. The feed assembly supplies sheets of exposed film to the developing, fixing and wash tanks l2, l3, 14. Film transfer mechanisms 21 are positioned in the tanks l2, 13, 14 for transporting the sheets of film supplied by the feeder sequentially through the tanks. An automatic dryer 22 is disposed within the main housing 11 to receive developed film sheets from the wash tank 14and to dry them. The dried film sheets are then discharged into a collecting bin 23 adjacent an outlet opening 24.

A drive motor 25 is positioned within the feed assembly housing 15. The drive motor 25 is connected to a drive shaft 26 which extends longitudinally of the main housing 11. The shaft 26 is in driving connection with the feed assembly 20, the film transfer mechanisms 21, and the dryer 22.

A removable cover 30 is positioned over the film feed assembly 20. The cover 30 includes a movable loading door 31 which may be opened to permit loading of exposed film sheets into the feed assembly 20. When the door 31 is closed, the cover 30 provides a light-tight encasing for the feed assembly 20 so that lights in the darkroom may be turned on as the film processor is operating.

Referring to FIG. 2, the film feed assembly 20 is shown in greater detail. A tray 32 is provided to receive film sheets-As will be explained in greater detail, the tray 32 is movably mounted to bring the film sheets into engagement with a feed roll assembly which sequentially transports the sheets of film to the developing tank 12.

Referring to FIG. 6 in conjunction with FIG. 2, the feed assembly housing includes a pair of

support plates

34, 35 The support plates are rigidly secured to and spaced from opposite walls of the housing 15 by suitable fastening means, not shown. The

support plates

34, 35 are notched at 36 and 37 to respectively removably receive feed

assembly support pins

38, 39. The

support pins

38, 39 are opposite ends of

frame cross bars

40, 41 respectively of a feed assembly frame. Sides of the feed assembly frame are provided by spaced

side plates

42, 43 which are secured to the

cross bars

40, 41 as by nuts 44.

A third cross bar assembly shown generally by the numeral 45 is similarly provided between the

side plates

42, 43 at a position above the tray 32. By this arrangement of a feed assembly supported by slot engaging pins, the entire feed assembly is rendered removable from the housing 15 simply by lifting it and simultaneously moving it to the left as viewed in FIGS. 1 and 2 to disengage the

pins

38, 39 from the

notches

36, 37.

Referring-to FIG. 3, the tray 32 slopes downwardly to the right and terminates at a discharge end adjacent a stripper bar 50 and beneath a large primary feed roll 51. The tray 32 is secured to a square shaft 52 which connects with an elevating mechanism as will be described. The discharge end of the tray 32 is movable between a down position indicated in phantom to an up position adjacent the primary feed roll 51. 8 When a stack of film sheets have been positioned on the tray 32, the lower or forward ends of the sheets abut the stripper bar'- 50. When the discharge end of the tray is elevated the top sheet of film is brought into contact with the primary feed roll 51. The primary feed roll 51 is a soft roll which frictionally engages the top film sheet. The primary feed roll 51 rotates counterclockwise as viewed in FIG. 3 and causes the top film sheet to travel with it and to feed between the feed roll 51 and idler rollers 53 positioned atop the stripper bar 50. The stripper bar'50 prevents movement of the remainder of the sheets of film in the stack and. accordingly, the top sheet of film is stripped from the stack and passed between the feed roll 51 and the idler rollers 53. 8

An upper and two secondary lower feed rolls 60, 61, 62 receive the film sheet after it passes between the feed roll 51 and the idler rollers 53. In accordance with one important aspect of the present invention, the

secondary rolls

60, 61 deflect the leading edge of the film sheet downwardly whereby trailing portions of the film sheet are biased upwardly against the primary feed roll 51. By this arrangement, the

secondary rolls

60, 61

serve to prevent trailing portions of a film sheet being fed from dragging across the stripper bar and being scratched thereby. The secondary rolls 60, 62 then direct the film sheet toward an opening 63 into the main housing 11.

The mechanism for elevating the tray 32 is best seen in FIGS. 2 and 4. The square shaft 52 is journaled in spaced bearings, not shown, which are carried by adjustable supports mounted on the

frame side plates

42, 43. A tray elevating link 71 is secured to one end of the shaft 52. The elevating link 71 is positioned outwardly of the frame side plate 42 and extends in an L- shaped configuration terminating in an apertured end portion 72.

A tension spring 73 engages the apertured end portion 72 of the link 71 and an apertured end portion 74 of an arm 75. The arm 75 is pivotally supported at 76 from the side plate 42. When the arm 75 moves to the position shown in phantom in Fig. 2, the spring 73 serves to pivot the link 71 as shown in phantom. Movement of the link 71 rotates the shaft 52 to elevate the discharge end of the tray 32, to move the stack of film sheets upwardly until the top sheet abuts the feed roll 51. The spring 73 provides a yieldable connection between the arm 75 and the link 71 such that the discharge end of the tray 32 is raised only sufficiently to allow the force exerted by the extended spring 73 to bring the entire length of the leading edge of the top sheet of film into contact with the feed roll 51 to effect feeding of the top film sheet between the feed roll 51 and the stripper bar 50.

Referring to FIG. 5, the bar 50 has three spaced notches 80 formed in its upper surface 81. U-shaped yokes 82 journal opposite ends of the idler rollers 53. The yokes 82 have depending threaded pins 83 secured thereto. The threaded pins 83 extend through apertures 83a in the bar 50. Helical springs 83b positioned in the apertures 83a concentric with the pins 83 bias the yokes 82 upwardly to hold the rollers 53 above the stripper bar 50 with just enough height and pressure to maintain the film in driving engagement with the feed roll 51. The upward travel of the yokes 82 relative to the bar 50 is limited by nuts 84 threaded on the lower ends of the pins 83. The purpose of the nuts 84 is to adjust the idler rollers 53 so they are parallel to the feed roll 51 and so they do not exert excessive pressure against the film which could result in deformation of film. The nuts 84 also adjust the upward travel of the yokes 82 to assure there is no contact between the feed roll 51 and the rollers 53 thereby avoiding excessive wear. The nuts 84 also maintain the yokes and rollers in proper position relative to the stripper bar during assembly and repair of the mechanism.

The rollers 53 extend slightly above the upper surface 81 of the bar 50 to maintain the film in driving engagement with the feed roll. They also serve to keep a leading edge portion of a sheet being fed, out of engagement with the stripper until the sheet is between the

secondary rolls

60, 61. As indicated previously, the secondary rolls cause a reverse bend in the film which maintains the film out of engagement with the stripper bar. By this arrangement, all but a very short leading edge portion of the film will stay out of engagement with the stripper bar 50 whether the rollers 53 are present or not and the rollers 53 and secondary rolls together serve as a film protection arrangement maintaining a sheet of film being fed out of contact with the stripper bar during its entire feed travel. By this arrangement the pressure of the film tray against the feed roller is released, in a manner which will be described presently, before leading portions of the feeding film can be scratched by burred edges of film or the tray which underlies the feeding film.

The stripper bar is supported by a C-shaped bracket 85. One leg of the C-shaped bracket terminates in a planar bearing surface 86 which engages the rear side 87 of the stripper bar 50. The other leg of the C-shaped bracket 85 carries a pair of upwardly extending fasteners 88. The fasteners 88 are threaded in regions 89 which extend through the brackets 85. The regions 90 of the fasteners 88 which extend upwardly beyond the lower leg of the bracket 85 are smooth and are slidably received in apertures 91 in the bar 50. A pair of compression springs 92 are carried by the regions 90 between the bar 50 and the bracket 85. The springs 92 bias the stripper bar 50 upwardly to facilitate adjust ment of the gap between the stripper bar 50 and the feed roll 51. With the gap set so only one film at a time can be fed through this gap, the stripper bar 50 is then fastened securely to the bearing surfaces 86.

Referring particularly to FIGS. 3 and 6, a support plate 100 is mounted

atopthe side plates

42, 43 and extends over the tray 32. Three U-shaped yoke brakets 101 are secured to the underside of the plate 100 and depend to a position near the tray 32. The yoke brackets 101 journal opposite ends of the shafts 102. Roller support arms 103 are pivotally supported intermediate their ends by the shafts 102. One end of each of the arms 103 journals a roller support shaft 104. The other end of each of the arms 103 is rigidly secured to a rod 105. Soft sponge rubber rollers 106 are rotatably supported on the roller support shafts 104. The rollers 106 are pivotally movable with the arms 103 about the shafts 102.

The rod 105 extends through each of the arms 103 and has crank arm portions 107 formed at each end. A roller 108 is rotatably mounted on the crank arm end portions of the rod 105. The two rollers 108 engage opposite upwardly turned flanges 109, 110 formed integrally with the tray 32, as best seen in Fig. 6. By this arrangement. when the tray 32 is down the rollers 108 are out of the way to allow for placement of film into the tray and to prevent interference with film feeding. When the tray 32 moves upwardly, therollers 108 are caused to move along the flange 109, 110 thereby pivoting the arms 103 about the shafts 102 in a counterclockwise direction as seen in FIG. 3. The soft sponge rubber rollers 106 are thereby caused to apply an increased pressure to the stack of film sheets as the tray 32 moves upwardly.

' The assembly. mounting the soft sponge rubber rollers 106 is removable and is used only at the option of the operator. Where the frictional characteristics between the feed roll and the film being fed are low, they are not used. Where the frictional characteristics are high. the sponge rollers 106 are used and serve dual functions. First, they serve to keep the film sheets from curling upwardly in the tray 32. Secondly, and more importantly, they serve to hold a large sheet of film in place when a small sheet on top of the large is being fed.

This second function is illustrated by the situation which occurrs when the top sheet of film on the stack is 3 inches in width and positioned at one side of the stack, while the second sheet in the stack is a full 17 inches in width. The forward corner portions of the larger film which is farthest away from the smaller film tends to cock upwardly into the feeding gap between the feed roll 51 and the rollers 53. This corner portion of the larger film commences to be fed between the feed rolls 51 and the rollers 53 concurrently with the smaller film. This cocks the large film with respect to the intended path of travel through the processor and a jam can result in a subsequent cycle when the large film is to be fed.

The soft roller assembly including the rollers 106 is an effective means of overcoming this problem, for the following reasons: First, as the tray 32 is raised toward the feed roll 51, the rollers 106 are pivoted downwardly against the stacked film. This engagement helps hold the film in the stack and prevents its curling upwardly. Second, the pressure between the film rollers 106 and the film stack causes the bottom portions of the rollers 106 to compress to form flatened regions. This compression provides a large surface area of contact be tween the rollers 106 and the film which holds the film firmly downwardly in the stack. Third, by regulating the amount of compression to which the rollers 106 are subjected, as well as the softness of the rollers 106, just enough pressure is exerted on the film stack to permit the smaller topmost sheet of film to be fed without pulling or scratching larger film sheets lower in the stack. Moreover, those of the rollers 106 which are not in contact with the smaller film sheet being fed will engage the larger sheet of film with sufficient friction to prevent its being cocked forwardly, thereby avoiding subsequent jamming of the feeding mechanism.

Referring to FIG. 7, the upper feed roll 51 is supported on a shaft 120. The shaft is journaled in bearings, not shown, carried by the

side plates

42, 43. One end of the shaft 120 carries a cam 121. The other end carries a toothed gear 122. Both the cam 121 and the gear 122 are keyed to the shaft 120 for rotation therewith. The gear 122 serves to drive the upper feed roll 51 and is, in turn, driven from agear, not shown, disposed within the housing 15 and connected with the drive shaft 26.

Referring to FIG. 4, a magnetically susceptible striker plate 123 is secured to and rotates with the gear 122. An electric magnet 124 is journaled on the. feed roll shaft 120 in a manner which permits the shaft to rotate freely in the magnet. When the magnet is energized it will be attracted to the striker plate 123 and will be caused to rotate with the gear 122.

An eccentric pin 125 is clamped by means of a collar 126 to the magnet 124. The eccentric pin is slidably disposed in a slot in the pivot arm 75. When the magnet 124 is energized, it rotates with the gear 122 causing the arm 75 to rotate about its piv-otal mounting 76, to elevate the discharge end of the tray 32, as previously explained. Once the rotation of the magnet has caused the tray 32 to elevate until the top sheet of film abuts the primary feed roll 51, the magnet will operate as a slip clutch, slipping relative to the striker plate 123 until de-energized. The tray is held upwardly by energization of the magnet 124 for only a brief interval, whereupon it is dropped. This brief interval is ordinarily sufficient to effect feeding of the top film sheet on the stack between the primary feed roll 51 and the stripper bar 50, but is not so long as to permit leading portions of the film being fed to drag on the tray or other sheets of film and be scratched thereby. Thus in contrast to the structure of the referenced patent where the tray is held up throughout the feed cycle and scratches resulted on occasions, the feed tray in the present device remains up in the present device only long enough to initiate film feeding.

Referring to FIG 9, the interval of energization of the magnet 124 is controlled by means of a resetting timer switch 150. The timer includes a motor which, upon being energized by the supply of current through

conductors

152, 153 will close a switch 154 so as to energize the magnet 124 for an interval such as seconds. At the end of the interval, the timer opens the switch 154 de-energizing the magnet. The switch 150 is of the resetting type which upon termination of energization of the motor 151 will reset in preparation for another cycle.

The lower feed roll 61 is mounted on a pair of support arms 130, one of which is shown in FIG. 3. The arms 130 are pivotally mounted at 131. The lower ends of the arms 130 engage limit switches 132 secured to the feed assembly frame. The limit switches 132 include spring biased plungers 133. By this arrangement lower roll 61 serves both as a feed roller and a detector roll. When a sheet of film passes between the

rolls

60, 61 the roll 61 will cause the arms 130 to pivot clockwise as seen in FIG. 3, thereby actuating the switches 132.

The detector switches 132 perform two control functions. First, through appropriate control cirucitry, upon sensing the presence of a sheet of film being fed, they signal the chemical supply system of the film processor which supplies developer and fixer to the

tanks

12, 13, 14. Thus, the supply of chemicals for processing is automatically carried out when film is being fed between the

rolls

60, 61. Second, upon sensing the passage of a sheet of film, the switches energize the electromagnet 124 to raise the film tray 32 to feed another sheet.

Referring to FIG. 8, the cam 121 is seen to be providcd with a series of circumferentially spaced lobes 140 which respectively actuate a limit switch 141. This limit switch operates a flashing light, not shown, to advise the operator as to whether or not the film feed mechanism is operating. Thus, when the flashing light stops, the operator knows that there is a malfunction in the feeding mechanism.

The feed roll 60 carries a double gear 145. One toothed perimeter of the double gear 145 engages a gear 146 carried by the roll 61. The outer toothed perimeter engages a gear 147 carried by the roll 62. The

rolls

60, 61, 62 are thereby coupled together for rotation. Rotation of the

rolls

60, 61, 62 is accomplished by drive means, not shown. disposed within the housing 15 and connected to the drive shaft 26.

Although the invention has been described in its preferred form with a certain degree of particularity, it is understood that the present disclosure of the preferred form has been made only by way of example and that numerous changes in the details of construction and the combination and arrangement of parts may be resorted to without departing from the spirit and scope of the invention as hereinafter claimed.

What is claimed is:

1. A film feeder for feeding sheets of X-ray film sequentially from the top of a stack of X-ray film sheets into a film processor, comprising:

a. film support means adapted to support a stack of sheets of film of varying sizes and to align a forward edge of each sheet of film with the forward edge of every other sheet in the stack;

b. stripping and feed means connected to the support means for stripping sheets of film from such stack one at a time and feeding such stripped sheets forward edge first into the film processor;

c. said stripper and feed means including a primary feed roll positioned above the film support means and positioned to contact the top one of a stack of sheets on the film support means, and stripper means positioned to block feeding movement of the remainder of the stack while the top sheet is being fed between the primary feed roll and the stripper means;

(1. said stripping and feed means further including upper and lower secondary feed rolls disposed on opposite sides of the film path to deflect downwardly film sheet portions which have passed between the primary feed roll and the stripper means for biasing trailing film portions which subsequently pass between the primary feed roll and the stripper means upwardly into engagement with said primary feed roll and away from said stripper means; and,

e. drive means rotating said primary and secondary feed rolls to advance each stripped sheet of film toward the processor.

2. The film feeder of claim 1 wherein:

a. said stripper means includes a stripper bar which is biased upwardly toward said primary feed roll; b. said stripper bar having roller means extending beyond its upper surface for maintaining feeding engagement between the film sheet being fed and said primary feed roll.

3. The film feeder of claim 1 wherein:

a. said secondary feed rolls comprise an upper secondary feed roll and first and second lower feed rolls;

b. said upper secondary feed roll and said first lower feed roll cooperating to deflect downwardly film sheet portions which have passed between said primary feed roll and said stripper bar; and,

c. said upper secondary feed roll and said second lower feed roll cooperating to direct film sheet portions which have passed between said upper secondary feed roll and said first lower feed roll toward the processor.

4. The film feeder of claim 1 additionally including:

a. a plurality of soft rollers disposed at spaced positions above said film support means to engage top sheets of film in the stack of film sheets;

b. means biasing said soft rollers into engagement with the top sheets of film;

c. whereby such of said soft rollers as are in engagement with the top most sheet of film being fed will rotate so as to permit feeding of the top most sheet, while such of said rollers as are in engagement with a larger sheet of film lower in the stack of'film sheets will not rotate thereby serving to hold lower, larger film sheets in place as smaller sheets of film at the top of the stack are fed sequentially between said primary feed roll and said stripper means.

(a) film support means for supporting a stack of film sheets;

(b) a film stripper positioned adjacent one end of said film support means for engaging the forward edges of the film sheets;

(c) primary fe'ed roll means including a primary feed roll positioned near said film support means and in closely spaced relation with said film stripper for engaging the forward edge of the top sheet of film to feed the top sheet of film between said primary feed roll and said film stripper;

(d) secondary feed roll means including upper and lower secondary feed rolls disposed on opposite sides of the path of film being fed between said primary feed roll and said film stripper for deflecting the film into engagement with said primary feed roll and away from said film stripper as the film passes between said primary feed roll and said film stripper, whereby the film is kept from dragging on said film stripper to prevent its being scratched by said film stripper. 1

6. The filmfeeder of claim 5 wherein:

b. means biasing said soft rollers into engagement with the top sheets of film; l

c. whereby such of said soft rollers as are in engagement with the top most sheets of film being fed will rotate so as to permit feeding of the top most sheet,

' while such of said rollers as are in engagement with a larger sheet of film lower in the stack of film sheets will not rotate thereby serving to hold lower, larger film sheets in place smaller sheets of film at the top of the stack are fed sequentially between said primary feed roll and said film stripper.

8. The film feeder of claim 7 wherein:

a. said film stripper includes a stripper bar which is biased upwardly toward said primary feed roll;

b. said stripper bar having roller means extending beyond its upper surface for maintaining feeding engagement between the film sheet being fed and said primary feed roll.

9. A film feeder for feeding sheets of X-ray film sequentially from the top of a stack of X-ray film sheets into a film processor, comprising:

a. film support means adapted to support a stack of sheets of film of varying sizes; b. stripping and feed means connected to the support means for stripping sheets of film from such stack one at a time and feeding such stripped sheets forward edge first into the film processor; 0. said stripping and feed means incuding a primary feed means positioned adjacent the film support 5 means and positioned to contact one of a stack of sheets on the film support means, and the stripper means positioned to block feeding movement of the remainder of the stack while the one sheet is being fed between the primary feed means and the 10 stripper means; and a d. said stripping and feed means further including film protection means for deflecting portions of the film being fed at a position downstream from said primary feed means to maintain film being fed in IS engagement with said primary feed means and away from said stripper means.

10. The feeder of claim 9 wherein said film protection means comprises a pair of secondary feed rolls on opposite sides of the film path to deflect portions of the film which have passed between the primary feed roll and stripper means.

11. The film feeder of claim 10 wherein:

a. said secondary feed rolls comprise an upper secondary feed roll and first and'second lower feed rolls;

c. said upper secondary feed roll and said second lower feed roll cooperating to direct film sheet por tions which have passed between said upper secondary feed roll and said first lower feed roll toward the processor.

12. The feeder of claim 10 wherein said film protection means additionally comprises idler rolls mounted on the stripper means.

13. The feeder of claim 12 wherein th idler rolls are yieldably mounted.

14. The film feeder of claim 9 wherein:

a. said stripper means includes a stripper bar which is biased upwardly toward said primary feed roll;

and, i a

b. said stripper bar has roller means extending beyond its upper surface for maintaining feeding engagement between the film sheet being fed and said primary feed roll.

15. The film feeder of claim 9 additionally including means for holding said film support means upwardly for only a brief timed interval so as to bring the top sheet of the film stack into contact with said primaryfeed means.

16. The film feeder of claim 15 wherein said holding 5 means comprises tray elevating means energized through resetting interval timer means.

17. In a film feeder having a film support means adapted to support a stack of X-ray film sheets of varying sizes, and having a primary feed means positioned 60 adjacent the film support means on one side of a film feed path to contact one of a stack of sheets on the film support means, the improvement of'a stripper assembly positioned on the other side of the film feed path, comprising:

(a) stripper means for blocking feeding movement of the remainder of the film sheets in the stack while one sheet is being fed between the primary. feed means and said stripper means said stripper means including a stripper bar having edge portions disposed to face the primary feed means;

-(b) film protection means including a plurality of spaced rollers carried by said stripper means and being biased into engagement with film being fed for maintaining film being fed in engagement with the primary feed means and away from said stripper means; and

(c) said rollers project outwardly from said edge portions toward the primary feed means.

18. In a film feeder having a film support means adapted to support a stack of X-ray film sheets of varying size, and having a primary feed means positioned adjacent the film support means on one side of a film feed path to contact one of a stack of sheets on the film support means, the improvement of a stripper assembly positioned on the other side of the film feed path, comprising:

(a) stripper means for blocking feeding movement of the remainder of the film sheets in the stack while one sheet is being fed between the primary feed means and said stripper means including a stripper bar and means for biasing said stripper bar upwardly toward the primary feed means; and

(b) film protection means including spaced roller means carried by and extending beyond the upper surface of said stripper bar and being biased into engagement with film being fed for maintaining feed engagement between film being fed and the primary feed means.

19. The stripper assembly of claim 18 wherein said roller means is yieldably mounted.

20. A method of feeding X-ray film sheets from a stack of film sheets into a film processor comprising the steps of:

a. aligning the forward edges of each sheet of film in the stack with the forward edge of every other sheet in the stack;

b. sequentially feeding the top sheets of film forward edge first between a primary feed roll positioned above the stack and a stripper bar positioned adjacent the forward edges of the sheets in the stack;

c. deflecting the portions of thesheets which have passed between the primary feed roll and the stripper bar downwardly to bias subsequent portions of the film sheets which pass between the primary feed roll and the stripper bar into engagement with the primary feed roll; and,

d. subsequently directing the film sheets into the film processor.

21. A method of preventing scratching of film sheets as they are being fed from a stack of film sheets between a primary feed roll and a stripper bar, comprising deflecting forward portions of the film sheet being fed to bias trailing film sheet portions toward the primary feed roll and away from the stripper bar as the trailing film portions pass between the primary feed roll and the stripper bar such that the trailing film portions ar kept from dragging on the stripper bar.

22. The method of claim 21 wherein the step of defleeting forward film portions is effected by disposing upper and lower secondary feed rollers on opposite sides of the path of film being fed between the primary feed roll and the stripper bar to engage and deflect forward portions of the film strip toward the stripper bar side of the film path to bias trailing portions of the film sheet toward the primary feed roll side of the film path. =9

Claims

1. A film feeder for feeding sheets of X-ray film sequentially from the top of a stack of X-ray film sheets into a film processor, comprising: a. film support means adapted to support a stack of sheets of film of varying sizes and to align a forward edge of each sheet of film with the forward edge of every other sheet in the stack; b. stripping and feed means connected to the support means for stripping sheets of film from such stack one at a time and feeding such stripped sheets forward edge first into the film processor; c. said stripper and feed means including a primary feed roll positioned above the film support means and positioned to contact the top one of a stack of sheets on the film support means, and stripper means positioned to block feeding movement of the remainder of the stack while the top sheet is being fed between the primary feed roll and the stripper means; d. said stripping and feed means further including upper and lower secondary feed rolls disposed on opposite sides of the film path to deflect downwardly film sheet portions which have passed between the primary feed roll and the stripper means for biasing trailing film portions which subsequently pass between the primary feed roll and the stripper means upwardly into engagement with said primary feed roll and away from said stripper means; and, e. drive means rotating said primary and secondary feed rolls to advance each stripped sheet of film toward the processor.

2. The film feeder of claim 1 wherein: a. said stripper means includes a stripper bar which is biased upwardly toward said primary feed roll; b. said stripper bar having roller means extending beyond its upper surface for maintaining feeding engagement between the film sheet being fed and said primary feed roll.

3. The film feeder of claim 1 wherein: a. said secondary feed rolls comprise an upper secondary feed roll and first and second lower feed rolls; b. said upper secondary feed roll and said first lower feed roll cooperating to deflect downwardly film sheet portions which have passed between said primary feed roll and said stripper bar; and, c. said upper secondary feed roll and said second lower feed roll cooperating to direct film sheet portions which have passed between said upper secondary feed roll and said first lower feed roll toward the processor.

4. The film feeder of claim 1 additionally including: a. a plurality of soft rollers disposed at spaced positions above said film support means to engage top sheets of film in the stack of film sheets; b. means biasing said soft rollers into engagement with the top sheets of film; c. whereby such of said soft rollers as are in engagement with the top most sheet of film being fed will rotate so as to permit feeding of the top most sheet, while such of said rollers as are in engagement with a larger sheet of film lower in the stack of film sheets will not rotate thereby serving to hold lower, larger film sheets in place as smaller sheets of film at the top of the stack are fed sequentially between said primary feed roll and said stripper means.

5. A film feeder for feeding sheets of film sequentially from the top of a stack of film sheets into a film processor, comprising: (a) fIlm support means for supporting a stack of film sheets; (b) a film stripper positioned adjacent one end of said film support means for engaging the forward edges of the film sheets; (c) primary feed roll means including a primary feed roll positioned near said film support means and in closely spaced relation with said film stripper for engaging the forward edge of the top sheet of film to feed the top sheet of film between said primary feed roll and said film stripper; (d) secondary feed roll means including upper and lower secondary feed rolls disposed on opposite sides of the path of film being fed between said primary feed roll and said film stripper for deflecting the film into engagement with said primary feed roll and away from said film stripper as the film passes between said primary feed roll and said film stripper, whereby the film is kept from dragging on said film stripper to prevent its being scratched by said film stripper.

6. The film feeder of claim 5 wherein: a. said secondary feed rolls comprise an upper secondary feed roll and first and second lower feed rolls; b. said upper secondary feed roll and said first lower feed roll cooperating to deflect downwardly film sheet portions which have passed between said primary feed roll and said film stripper; and, c. said upper secondary feed roll and said second lower feed roll cooperating to direct film sheet portions which have passed between said upper secondary feed roll and said first lower feed roll toward the processor.

7. The film feeder of claim 6 additionally including: a. a plurality of soft rollers disposed at spaced positions above said film support means to engage top sheets of film in the stack of film sheets; b. means biasing said soft rollers into engagement with the top sheets of film; c. whereby such of said soft rollers as are in engagement with the top most sheets of film being fed will rotate so as to permit feeding of the top most sheet, while such of said rollers as are in engagement with a larger sheet of film lower in the stack of film sheets will not rotate thereby serving to hold lower, larger film sheets in place as smaller sheets of film at the top of the stack are fed sequentially between said primary feed roll and said film stripper.

8. The film feeder of claim 7 wherein: a. said film stripper includes a stripper bar which is biased upwardly toward said primary feed roll; b. said stripper bar having roller means extending beyond its upper surface for maintaining feeding engagement between the film sheet being fed and said primary feed roll.

9. A film feeder for feeding sheets of X-ray film sequentially from the top of a stack of X-ray film sheets into a film processor, comprising: a. film support means adapted to support a stack of sheets of film of varying sizes; b. stripping and feed means connected to the support means for stripping sheets of film from such stack one at a time and feeding such stripped sheets forward edge first into the film processor; c. said stripping and feed means incuding a primary feed means positioned adjacent the film support means and positioned to contact one of a stack of sheets on the film support means, and the stripper means positioned to block feeding movement of the remainder of the stack while the one sheet is being fed between the primary feed means and the stripper means; and d. said stripping and feed means further including film protection means for deflecting portions of the film being fed at a position downstream from said primary feed means to maintain film being fed in engagement with said primary feed means and away from said stripper means.

11. The film feeder of claim 10 wherein: a. said secondary feed rolls comprise an upper secondary feed roll and first and second lower feed rolls; b. said upper secondary feed roll and said first lower feed roll cooperating to deflect downwardly film sheet portions which have passed between said primary feed roll and said stripper bar; and, c. said upper secondary feed roll and said second lower feed roll cooperating to direct film sheet portions which have passed between said upper secondary feed roll and said first lower feed roll toward the processor.

13. The feeder of claim 12 wherein th idler rolls are yieldably mounted.

14. The film feeder of claim 9 wherein: a. said stripper means includes a stripper bar which is biased upwardly toward said primary feed roll; and, b. said stripper bar has roller means extending beyond its upper surface for maintaining feeding engagement between the film sheet being fed and said primary feed roll.

16. The film feeder of claim 15 wherein said holding means comprises tray elevating means energized through resetting interval timer means.

17. In a film feeder having a film support means adapted to support a stack of X-ray film sheets of varying sizes, and having a primary feed means positioned adjacent the film support means on one side of a film feed path to contact one of a stack of sheets on the film support means, the improvement of a stripper assembly positioned on the other side of the film feed path, comprising: (a) stripper means for blocking feeding movement of the remainder of the film sheets in the stack while one sheet is being fed between the primary feed means and said stripper means said stripper means including a stripper bar having edge portions disposed to face the primary feed means; (b) film protection means including a plurality of spaced rollers carried by said stripper means and being biased into engagement with film being fed for maintaining film being fed in engagement with the primary feed means and away from said stripper means; and (c) said rollers project outwardly from said edge portions toward the primary feed means.

18. In a film feeder having a film support means adapted to support a stack of X-ray film sheets of varying size, and having a primary feed means positioned adjacent the film support means on one side of a film feed path to contact one of a stack of sheets on the film support means, the improvement of a stripper assembly positioned on the other side of the film feed path, comprising: (a) stripper means for blocking feeding movement of the remainder of the film sheets in the stack while one sheet is being fed between the primary feed means and said stripper means including a stripper bar and means for biasing said stripper bar upwardly toward the primary feed means; and (b) film protection means including spaced roller means carried by and extending beyond the upper surface of said stripper bar and being biased into engagement with film being fed for maintaining feed engagement between film being fed and the primary feed means.

20. A method of feeding X-ray film sheets from a stack of film sheets into a film processor comprising the steps of: a. aligning the forward edges of each sheet of film in the stack with the forward edge of every other sheet in the stack; b. sequentially feeding the top sheets of film forward edge first between a primary feed roll positioned above the stack and a stripper bar positioned adjacent the forward edges of the sheets in the stack; c. deflecting the portions of the sheets which have passed between the prImary feed roll and the stripper bar downwardly to bias subsequent portions of the film sheets which pass between the primary feed roll and the stripper bar into engagement with the primary feed roll; and, d. subsequently directing the film sheets into the film processor.

21. A method of preventing scratching of film sheets as they are being fed from a stack of film sheets between a primary feed roll and a stripper bar, comprising deflecting forward portions of the film sheet being fed to bias trailing film sheet portions toward the primary feed roll and away from the stripper bar as the trailing film portions pass between the primary feed roll and the stripper bar such that the trailing film portions are kept from dragging on the stripper bar.

22. The method of claim 21 wherein the step of deflecting forward film portions is effected by disposing upper and lower secondary feed rollers on opposite sides of the path of film being fed between the primary feed roll and the stripper bar to engage and deflect forward portions of the film strip toward the stripper bar side of the film path to bias trailing portions of the film sheet toward the primary feed roll side of the film path.