US3710457A

US3710457A - Answer sheets

Info

Publication number: US3710457A
Application number: US00164796A
Authority: US
Inventors: S Rechdahl; D Folske
Original assignee: Minnesota Mining and Manufacturing Co
Current assignee: 3M Co
Priority date: 1971-07-21
Filing date: 1971-07-21
Publication date: 1973-01-16
Anticipated expiration: 1990-01-16

Abstract

A set of answer sheets for use with an automatic test grading device of the type wherein stacked answer sheets are held by pin means in a position for scanning of answer indication areas placed upon each answer sheet and wherein the scanned answer sheets are fed seriatim from the stack. Each answer sheet has a registration edge and answer indication areas of a predetermined configuration, which answer indication areas are placed upon each sheet in a prescribed relationship to the registration edge. Each answer sheet contains an aperture which is positioned in a prescribed relationship to the answer indication areas and is positioned in a prescribed relationship to and closely adjacent the registration edge. The aperture edge and the registration edge define a holding strip of varying width between the aperture and the registration edge, wherein the narrowest portion of the holding strip defines a separation region of a predetermined width between the aperture and the registration edge. For 4 mil thick sheets the separation region is approximately 22 mils wide. Portions of the aperture edge are shaped for registering each sheet with a pin means adjacent the separation region. Portions of the aperture edge in common with the holding strip and adjacent the registering portions of the aperture edge on opposite sides of the registering portions from the separation region define two clearance edges. The two clearance edges converge toward each other in a direction toward the registration edge and thereby enable the holding strip to deflect to concentrate tension in the separation region when the holding strip of a registered sheet is forced against the pin means. The two clearance edges are preferably straight edges.

Description

United States Patent 3 1 1 Rechdahl et al.

[54] ANSWER SHEETS [75] Inventors: Segwald J. Rechdahl, Fridley; Donald W. Folske, Oakdale, both of Minn.

[73] Assignee: Minnesota Mining and Manufacturing Company, Saint Paul, Minn.

22 Filed: July 21,1971

[21] Appl. No.: 164,796

I Related U.S. Application Data [63] Continuation-in-part of Ser. No. 869,002, Oct. 24,

1969, abandoned.

[52] US. Cl...... ..35/48 A, 402/79 [51] Int. Cl. ..G09b B23b [58] Field of Search ..35/48; 271/36, 61; 402/79 [56] References Cited UNITED STATES PATENTS 3,203,116 8/1965 Shaw et a]. ..35/48 A 1,242,019 10/1917 Moore 2,391,125 12/1945 Carpenter ..402/79 ABSTRACT A set of answer sheets for use with an automatic test grading device of the type wherein stacked answer [11] 3,710,457 51' Jan. 16, 1973 sheets are held by pin means in a position for scanning of answer indication areas placed upon each answer sheet and wherein the scanned answer sheets are fed seriatim from the stack. Each answersheet has a registration edge and answer indication areas of a predetermined configuration, which answer indication areas are placed upon each sheet in a prescribed relationship to the registration edge. Each, answer sheet contains an aperture which is positioned in a prescribed relationship to the answer indication areas and is positioned in a prescribed relationship to and closely adjacent the registration edge. The aperture edge and the registration edge define a holding strip of varying width between the aperture and the registration edge, wherein the narrowest portion of the holding strip defines a separation region of a predetermined width between the aperture and the registration edge. For 4 mil thick sheets the separation region is approximately 22 mils wide. Portions of the aperture edge are shaped for registering each sheet with a pin means adjacent the separation region. Portions of the aperture edge in common with the holding strip and adjacent the registering portions of the aperture edge on opposite sides of the registering portions from the separation region define two clearance edges. The two clearance edges converge toward each other in a direction toward the registration edge and thereby enable the holding strip to deflect to concentrate tension in the separation region whenv the holding strip of a re gistered sheet is forced against the pin means. The two clearance edges are preferably straight edges.

11 Claims, 12 Drawing Figures A 6/4 A hkh'eheeemsze N\ n o n T n n n n n n n T n 0 T ill u u U u u u u u u u u u U u n T n o n n n n n n T n n T n u U u U \L U u U U u u U U U U n n n n n T n n n T n n tr) 0 n U U 1L 0 u u u u U U U u U n n n n n n n o H n n n n n u u U' u 0 J; u \L u u u u u u n n n n n n n n n n n n n n U U u U U U 3 U U U U u u u L l I 1 ANSWER SHEETS CROSS REFERENCE TO RELATED APPLICATION This application is a continuation-in-part of our copending application Ser. No. 869,002, filed Oct. 24, 1969 now abandoned. This application is related to the copending application filed by John L. Roche on Feb. 10, 1069, Ser. No. 798,016, now US. Pat. No. 3,601,906, and to the application filed by the present inventors on Oct. 24, 1969, Ser. No. 868,996, now US. Pat. No. 3,586,318.

BACKGROUND OF THE INVENTION The present invention relates to an answer sheet for use with a test grading device, and is particularly directed to an answer sheet for use with a test grading device of the type wherein a stack of answer sheets is held by pin means in a position for scanning of the answer indication areas which are placed on each answer sheet, and wherein the scanned answer sheets are fed seriatim from the stack for removal from the scanning position. A test grading device of this particular type is described in US. Pat. application Ser. No. 798,016 by Roche, filed on Feb. 10,1969.

In accordance with the description of the test grading device set forth in the Roche application, a stack of answer sheets, each having a predetermined configuration of answer indication areas placed thereon in a prescribed relationship to a registration edge of the sheet, is placed on supporting means in a givenlposition for the scanning of the answer indication areas of each sheet. This given position is defined by guide means such as bars which are disposed adjacent the supporting means. Once the stack of sheets is in the given position, a pin means such as a sharpened needle-like pin is driven through the stack in order to hold the sheets in the given position. The answer indication areas of the outside sheet in the stack are scanned and the answer indications which are sensed in the scanned answer indication areas are compared with answer indications sensed from corresponding answer indication areas of an answer key. From such comparisons, each answer sheet is scored. Following the scanning of each sheet, the scanned sheet is engaged by removal means, such as feed means, which feed the scanned sheet from the 1 pin, thereby removing the scanned sheet from the scanning position.

The predetermined configuration of answer indication areas is placed upon the answer sheet in a prescribed relationship to the registration edge of the sheet so that the scanning of the answer indication areas of theanswer sheet is synchronized with the scanning of the corresponding answer indication areas of the answer key. The answer key has a fined position in relation to the guide means and in relation to the stack holding position of the pin means. The degree to which each answer sheet of a stack can be placed in a position corresponding with the position of the other sheets in the stack, or-can be positioned for insuring that the scanning of the answer indication areas of each answer sheet is synchronized with the scanning of the corresponding answer indication areas of an answer key, is limited by human ability and diligence in uniformly stacking the sheets when placing them against the guide means'and by the holding capability of the pin means. 1

Certain difficulties have arisen in the use of the above-described answer sheet of the prior art. For example, when the sheets are separated from the needlelike pin means, the tearing is ragged and there is an appreciable residue of debris resulting from the tearing. When larger pin means are used, multiple tearing of the sheets also results. Also, there is a tendency of the priorart answer sheets to either be doublefed or mis-fed from the given position upon operation of the feeding means.

It is desirablethat the answer sheets have characteristics which tend to reduce the probability of double feeding or mis-feeding thereof.

It is also desirable that each sheet consistently tear in a defined separation region having a predetermined width, thereby minimizing the range of the predetermined feeding force.

It is additionally desirable that the tearing of each sheet not be ragged since ragged tearing inhibits uniform stacking of fed sheets for scanning of the opposite surface thereof with a second registration edge positioned against the guide-means.

It is further desirable that the residue of debris resulting from'the tearing be appreciably minimized since the debris tends to inhibit consistent feeding of the remaining answer sheets.

It is still further desirable that an answer sheet having I the aforementioned characteristics be capable of being positioned for synchronized scanning of the answer indication areas placed thereon, with the corresponding answer indication areas of an answer key.

SUMMARY OF THE INVENTION The present invention provides that in a set of answer 7 sheet with a pin means adjacent a separation region of a predetermined width between the aperture and the registration edge. The aperture is positioned in a prescribed relationship to the answer indication areas of the answer sheet in order to assure synchronized scanning of the corresponding answer indication areas of the answer sheet and the answer key. The aperture is positioned in a prescribed relationship to and closely adjacent the registration edge of the sheet for defining a holding strip of varying width between the aperture and the registration edge. The narrowest portion of the holding strip defines the separation region, the preferable predetermined width of which is approximately 22 mils. Portions of the aperture in common with the holding strip and adjacent the registering portions of the aperture edge on opposite sides of the registering portions from the separation region define two clearance edges. The two clearance edges converge toward each otherin a direction toward the registration edge for enabling the holding strip to deflect to concentrate tension in the separation region when the holdingstrip of a predetermined force, reliability of feeding is increased, each fed sheet is consistently and more cleanly mm in the separation region, and the residue of debris is appreciably reduced.

Concentration of tension in the separation region is increased by providing that the two clearance edges be straight edges.

It is preferred that the aperture be centered along the registration edge of the sheet so that the changes in paper size due to changes in humidity and the like are equally distributed from the center of the answer sheets, thereby minimizing any departure from exact synchronization of the corresponding answer indication areas of the answer sheet and the answer key.

It is also preferred that the registration edge is a straight edge and that the aperture is symmetrical about an axis perpendicular to the registration edge.

The reliability with which answer sheets may be registered in and fed from the test grading device may be further increased by providing certain combinations of various species of answer sheets, pin means and feed means. The features of some of these combinations are set forth in the following discussion of a sheet and sheet registration and feeding apparatus combination, which is the subject of the above referenced U.S. patent by the present inventors. This sheet and sheet registration and feeding apparatus combination which may include sheets other than answer sheets, improves reliability in sheet registration and feeding by providing certain features in the pin means and feed means which are used in combination with a stacked set of sheets such as the set of answer sheets of the present invention. Such reliability is also improved by providing certain additional features in the set of sheets in relation to the particular pin means and feed means with which the sheets are combined.

In accordance with the aforesaid combination, which includes sheets according to the present invention and pin means shaped for registration with the registering portions of the aperture edge of each sheet, the feed means are positioned for engaging the outside sheet of a registered stack of sheets and for feeding the engaged sheet from the registered stack with a predetermined force. The feed means include feed legs which are positioned on each side of the pin means for engaging the outside registered sheet at positions adjacent the registration edge beyond each side of the aperture; and the feed legs are spaced apart by a predetermined distance for causing deflection of the holding strip to concentrate tension in the separation region when the holding strip is forced against the pin means by the feed legs feeding the registered and engaged sheet from the stack. The feed legs are also spaced apart by a predetermined distance for enabling the feeding of the engaged sheet from the stack; that is, the feed legs must be placed close enough together to cause sufficient force to be applied between the holding strip and the pin means to enable the tearingof the holding strip upon the operation of the feed means. If the feed legs are not placed close enough together to provide this sufficient force relationship between the holding strip and the pin means, the feed legs may ride over or bend the registered sheet rather than feed the registered sheet from the given position.

The feed means include elements on the feed legs for engaging the feed legs with the registration edge of an outside registered sheet for enabling the feed legs to push against the engaged registration edge to feed the engaged sheet from a registered stack, and for applying a force to compress the stack for aligning the registration edge of the outside registered sheet with the feed legs to enable the engagement of the feed legs with the registration edge. Absent the compression of the stack, the registration edge of a sheet may be bent so that the registration edge is not aligned for engagement with both feed legs.

The feed legs are variably disposed to the holding means for the stack in response to variations in the size of the stack; and the feed means include spring means for providing the force which is applied for compressing the stack of sheets. These spring means are operatively responsive to a variation in the disposition of the-feed legs in response to a reduction in the size of the stack for decreasing the provided applied compressive force as the size of the stack is reduced.

In an embodiment wherein each sheet is of a predetermined thickness, each feed leg includes a step for applying the force for compressing the stack and for engaging the registration edge of the outside registered sheet. Each step comprises a plate having a surface disposed for pressing against the exposed surface of the outside registered sheet adjacent the registration edge thereof, for applying the compressive force and a riser joined to the pressing surface of the plate, for engaging the registration edge of the outside registered sheet and for pushing against the registration edge to feed the engaged outside registered sheet from the stack upon the operation of the feeding means. The thickness of the step provided by the riser is not greater than the thickness of each sheet. The thickness of the step provided by the riser is defined as the distance between the plate and the position where the riser contacts the registration edge of the outside registered sheet.

It is preferred that the riser have a V-shaped edge for pushing against the registration edge of the outside registered sheet. The surface of the riser which is joined to the pressing surface of the plate is disposed at an acute angle to the pressing surface and the thickness of the step provided by the riser is less than the thickness of each step. However, the thickness of the riser is slightly greater than the thickness of each sheet. The thickness of the riser is defined as the distance between the ends of the arms of the V.

In one preferred embodiment, the registration edge of each sheet is smooth for enabling penetration of the registration edge of the outside registered sheet by the V-shaped riser edge and for enabling holding by the registration edge of the penetrating riser edge. A smooth edge is defined as the type of edge obtained when cutting paper with a sharpened guillotine cutter or sharpened slitter cutter, in contrast to the type of edge obtained by cutting paper with a dull slitter cutter or a dull guillotine cutter.

In a preferred embodiment, wherein each sheet is of a given width between the aperture and the edge opposite the registration edge, means are provided for When the feed legs including the above-described steps are used in combination with the above-described sequence-maintaining means, the force provided by the plate to a sheet during feeding prevents buckling of the sheet near the registration edge thereof.

It is preferred that the two clearance edges are straight edges; that the pin means has a curved holding surface and that the pin means is disposed for registering the curved holding surface with the two straight edges. It is also preferred that the aperture of each sheet is an isoceles triangle with the vertex adjacent the separation region and with the base parallel to the registration edge; that the pin means have a semi-circular holding surface and that the pin means is disposed for registering the flat surface of the pin means with the base of the aperture.

In a preferred embodiment, the dimensions of the registering portions of the aperture edge are slightly larger'than the corresponding dimensions of the pin means, thereby preventing a snug registration; and the feed legs are disposed for dragging across the outside registered sheet during an interval between the feeding of the fed sheet and the engagement of the next outside registered sheet, which dragging provides a small opening between the pin means and the holding strip of the outside registered sheet.

A snug registration is undesirable for the following reasons. A snug registration makes the registering of the sheets on the pin means more difficult; a snug registration impedes compression of the sheets for aligning the registration edge of the sheets with each step of the feed legs; a snug registration increases the likelihood of tearing the edges of the aperture while registering the sheets on the pin means.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 illustrates an answer sheet of a set of answer sheets accordingto the present invention.

FIG. 2 illustrates in perspective a sheet registration and feeding apparatus in combination with a set of answer sheets according to the present invention, such as the answer sheet illustrated in FIG. 1. In FIG. 2, the answer indication areas are not shown on the answer sheet.

FIG. 3 is another perspective view of the sheet registration and feeding apparatus and answer sheet set combination illustrated in FIG. 2.

FIG. 4 is a top view of the feed means shown in the sheet registration and feedingapparatus illustrated in FIGS. 2 and 3;

FIG. 5 is a sectional view taken along and in the direction of line 5-5 in FIG. 4, which view illustrates a feed leg with a step attached thereto for compressing a set of stacked registered answer sheets and for engaging the outside sheet of the registered stack.

FIG. 6 is a perspective view of an embodiment of feed legs for engaging and feeding the outside sheet of the registered stack, which embodiment is alternative to that shown in FIGS. 2-5.

FIGS. 7a-7e illustrate various alternative embodiments of the registration edge, aperture and holding strip of an answer sheet according to the present invention. Pin means for registration with the illustrated apertures are shown by dashed line. I

FIG. 8 illustrates another alternative embodiment of the aperture and clearance edges of an answer sheet according to the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG. 1, an answer sheet, ofa set of answer sheets according to the present invention, has answer indication areas placed thereon for questions l25. The predetermined configuration of answer indication areas areplaced in a prescribed relationship to the registration edge 10 of the answer sheet so that the scanning of the corresponding answer indication areas of the answer sheet and an answer key is synchronized.

The answer sheet contains an aperture 12 positioned in a prescribed relationship to the answer indication areas, thereby insuring synchronized scanning when the answer sheet is registered on pin means such as the pin means 14 shown by dashed line in FIG. 1. The aperture 12 is positioned in a prescribed relationship to and closely adjacent the registration edge 10. The aperture edge 13 and the registration edge 10 define a holding strip 16 of varying width between the aperture 12 and the registration edge 10. The narrowest portion of the holding strip 16 defines a separation region 18 of a predetermined width between the aperture 12 and the registration edge 10. The aperture 12 is symmetrical about a line 20 which is perpendicular to the registration edge 10. The separation region 18 lies along this line 20.

It is seen that portions of the aperture edge 13 are shaped for registering the answer sheet with the pin means 14 adjacent the separation region 18. Two portions of the aperture edge 13 in common with the hold ing strip 16 and adjacent the registering portions 21 on opposite sidesof the registering portions 21 from the separation region 18 define two clearance edges 22. The two clearance edges 22 converge toward each other in a direction toward theregistration edge 10 and thereby enable the holding strip 16 to deflect to concentrate tension in the separation region 18 when the holding strip 16 is forced against the pin means 14.

In the preferred embodiment, the clearance edges 22 are straight edges and the aperture 12 is centered along the registration edge 10.

The preferred embodiment of the set of answer sheets of the present invention may be registered with a pin means 14, such as a pin having a semi-circular crosssectional dimension, wherein the diameter is 0.250 inches (approximately 6.4 millimeters) and be fed by feed means which feed the answer sheets with a predetermined force which is in the range of 20 to 25. ounces (approximately 5.6 to 7.0 newtons). This preferred embodiment comprises a paper sheet approximately 4 mils (approximately 0.1 mm) thick in which the aperture 12 is an isoceles triangle having a base 05 inches (approximately 1.3 centimeters) in length paral- Ielto the registration edge 10, and having a separation. region 18 of a predetermined width of approximately 22 mils (approximately 0.56 millimeters) between the triangle vertex and the registration edge 10. We have found that for a 4 mil thick sheet the separation region width, which is stated to be approximately 22 mils, may be from 20 to 35 mils. The sheet is approximately 11 inches (approximately 28 centimeters) along the registration edge and has a given width between the aperture l2 and the edge 24 opposite the registration edge of approximately 4 inches (approximately 10 centimeters). The height of the triangle is 0.173 inches (approximately 4.4 millimeters). DATA brand OCR Bond 20 No. paper, available from International Paper Company of New York, N.Y., is preferred, and all sheets in a set preferably have the fiber running in the same direction in relation to the registration edge. The preferred answer sheets have 82 percent reflectance and a 84 percent opacity for a 4 mil thick sheet, which is sufficient to prevent marks on one surface of the answer sheet to be sensed by optical sensing means when scanning the opposite surface of the answer sheet. The paper has an average smoothness of 112 Sheffield units.

In one preferred embodiment, answer indication areas are provided on each surface of the answer sheet, and

apertures

12 and 26 adjacent registration edges 10 and 24, respectively, are provided, thereby doubling the question capacity of each answer sheet.

Answer indications are shown in various of the answer indication areas of the answer sheet of FIG. 1.

A set of answer sheets 30 is shown in combination with feed means 32 and holding means 34 in FIGS. 2-5. The holding means 34 comprises means 36, a table 38 and guide means such as the bars 40, for receiving and supporting the set of sheets 30 in stacked registration with the pin means 36.

The pin means 36 prevent lateral movement of the sheets and the bars 40 in combination with the pin means 36 prevents rotational movement of the sheets. The table 38 is slidably mounted on the frame 41 so that the pin means 36 can be pulled out from under the feed means 32 when a set of sheets is registered on the pin means 36.

The feed means 32 comprises feed legs 42 and a spring 44 for providing a predetermined force to move the feed legs 42 for feeding answer sheets from the stack 30. The feed legs 42 are positioned on each side of the pin means 36 at positions adjacent the registration edge 10 beyond each side of the aperture 12. The feed legs 42 are attached by supporting

members

46, 48 and 50 to a base plate (not shown) as described in the aforementioned US. Pat. Application by Roche. This base plate is slidably mounted in a holder (not shown) which is positioned in a stationary relationship to the frames 41 supporting the holding means 34. The apertures 52 in the supporting members 50 are for coupling the feed means 32 to the base plate. The base plate and the feed means 32 may be slidably positioned in either a cocked or a forward position. The feed means 32 is shown in the cocked position in FIGS. 25. The feed legs 42 when operated move from this cocked position to a forward position for removing an answer sheet such as fed answer sheet 54 from the registered stack 30 to a stopped position, such as that in which the fed sheet 54 is shown.

The feed means 32 include means such as steps 56 for engaging the feed legs 42 with the registration edge 10 of an outside registered sheet 58 of the stack 30 for enabling the feed legs 42 to push against the engaged outside registered sheet 58 to feed the engaged sheet 58 from the stack 30. The steps 56 also are means by which the feed means 32 applies a force to compress the stack 30 for aligning the registration edge 10 of the outside sheet 58 with the feed legs 42 to enable the feed legs 42 to engage the registration edge 10.

The table 38 includes a bench 59 positioned beneath the cocked position of the feed legs. The steps 56 rest on the bench 59 when no sheets are registered on the pin means 36.

Each step 56 comprises a plate 60 and a riser 62. The plate 60 is disposed for pressing against the exposed surface 64 of the outside registered sheet 58. The plate 60 is also disposed adjacent the registration edge 10 of the outside registered sheet 58 to apply the force for compressing the stack 30. This applied force is.provided by spring means such as the spring 66. The riser 62 is joined to the pressing surface 68 of the plate 60 for engaging the registration edge 10 of the outside registered sheet 58 and for pushing against the registration edge 10 to feed an engaged outside registered sheet 58 from the stack 30 upon the operation of the feeding means 32. Each sheet in the stack 30 is of a predetermined thickness and the thickness of the step provided by the riser 62 is not greater than the thickness of each sheet of stack 30. The riser 62 has a V-shaped edge for pushing against the registration edge 10 of the outside registered sheet 58. It is seen in FIG. 5 that the surface 70 of the riser 62 which is joined to the pressing surface 68 of the plate 60 is disposed at an acute angle to the pressing surface 68. The thickness of the step provided by the riser 62 is the distance between the point of the V where the riser engages the registration edge 10 and the pressing surface 68 of the plate 60, the thickness of the riser 62, however, being the distance between the ends of the arms of the V". The thickness of the riser 62 is slightly greater than the thickness of each sheet of the stack 30. The registration edge 10 of each sheet is preferably smooth for enabling the V-shaped edge of the riser 62 to penetrate the registration edge 10 for enabling registration edge 10 to hold the penetrating edge of the riser 62. I

An alternative embodiment of the steps 56 is shown in FIG. 6. In this alternative embodiment, the steps 72 are also attached to the feed legs 42. However, in this embodiment the riser edge is a vertical surface provided by member 74 adjacent the plate 76. The plate 76 is disposed at a slight angle to the horizontal surface of the outside registered sheet 58 of the stack 30.

The force provided by the spring means 66 is transmitted to the feed legs 42 by the supporting member 48. Referring to FIG. 2, it is seen that the spring 66 is fastened to the supporting member 50 by fastening member 80. The other end of the spring 66 is fastened to an extension 82 of the supporting member 48 which passes through an aperture 84 in the supporting member 50. Extension 82 is' loosely pivotally connected to supporting member 50 by means of pin 85. The feed legs 42 are thereby self-leveling so that each feed leg 42 can engage the registration edge 10 of the outside registered sheet 58. It is seen by this combination of spring means 66, supporting member 48 and feed legs 42 that the feed legs 42 are variably disposed to the holding means 34 in response to variations in the size of the registered stack 30 and that the spring means 66 is operatively responsive to a variation in the disposition of the feed legs 42 in response to a reduction in size of the registered stack 30 for decreasing the provided applied compressive force as the size of the stack 30 is reduced.

The feed legs 42 are centered about the pin means 36 by supporting member 46 and the rails 86.

Means are also provided for maintaining fed sheets such as sheet 54 in the sequence in which stacked in the registered stack 30. The sequence-maintaining means comprise a stop 88 which disposed on the holding means 34 for stopping movement of each fed sheet 54. Each sheet of the stack 30 is of a given width between the aperture 12 and the edge 24 opposite the registration edge 10. The distance between the stop 88 and the pin means 36 is less than approximately twice the given width between the aperture l2 and the opposite edge 24. By so placing the stop 88 this predetermined distance from the pin'means 36, the registration edge of a fed sheet rests on and overlapping the opposite edge 24 of the outside registered sheet 58 of the stack 30. Therefore, as each sheet 54 is fed from the stack 30, it is positioned beneath the previously fed sheets 54 and the fed sheets are maintained in the same sequence as in which they were originally stacked.

The feed force of the feed means 32 is greater than the force required to separate the sheet at the separation region 18 plus the frictional force provided upon operation of the feed means 32 between the outside registered sheet 58 and the second registered sheet 78 due to the pressure provided by the plates 60.

When the sequence-maintaining means 88 is included, the feed force of the feed means 32 is greater than the force required to separate the sheets at the separation region 18 plus the frictional force provided upon operation of the'feed means 32 between the outside registered sheet 58 and the second registered sheet,

78 due to the pressure provided by the plates 60 plus the frictional resistance force due to the weight of the stack of the removed sheets 54 in resting upon the sheets remaining in the stack 30.

Also, the coefficient of friction of the table 38 is preferably as large as the coefficient of friction of each sheet in the stack 30.

The stiffness of each sheet is sufficient to prevent buckling of the bottom sheets of the stack 30'of a predetermined quantity of sheets, when the bottom sheets are fed from the pin means 36 beneath the stack of fed sheets 54.

For seriatim feeding of sheets having the dimensions set forth hereinabove for a set of answer sheets such as illustrated in FIG. 1, from pin means 36 also having the dimensions set forth hereinabove, the inside edges of the feed legs 42 are spaced apart by from 0.69 to 0.81 inches (approximately 1.8 to 2.1 centimeters). The plates are each 0.38 inches (approximately 9.7 millimeters) (parallel to the the registration edge 10) by 0.5 inches (approximately 1.3 centimeters) and 0.06 inches (approximately 1.5 millimeters) thick.

The spring 44, when in a cocked position, provides a force in the range of from 25 to 30 ounces (7.0 to 8.3 newtons). When the feed means is operated, the

predetermined feeding force provided at the feed legs tions and pin means 14 configurations according to the present invention provide reliable sheet feeding. These various combinations are illustrated in FIG. 7. In all five configurations shown, as well as in the configuration shown in FIG. 1, the width of the separation region 18 between the aperture 12 and the registration edge 10 is a predetermined width. The registration edge may include a rectangular notch as shown in FIG. 7a, a curved groove 92 as shown in FIGS. 7b and 7d, or a slit 94 as shown in FIG. 7c. In the combination shown in FIG. 70, the predetermined width of the separation re gion 18 is the distance between the aperture 12 and the end of the slit 94 nearest the aperture 12.

The pin means 14 may be semi-circular, as illustrated in FIGS. 1, 7a, 7b or 7d, or round, as illustrated in FIGS.7c and 7e. Other pin shape-s may also be used, however, theillustrated shapes are preferred.

The combination of a pin having a curved surface with an aperture having straight edges such as illustrated in FIGS. 1, 7a, 7b and 7c was found to provide the best combination of reliable feeding and consistent clean separation in the separation region. Providing curved aperture edges adjacent the holding strip 16 in combination with the pin having a curved surface such as is illustrated in FIGS. 7d and 7e also produces reliable feeding, however, the tears for the configuration illustrated in FIG. 7d, while consistently in the separation region, were sometimes ragged.

The registration provided by the combination of FIG. 7d is less precise than provided by the other combinations shown, but is acceptable when synchronization tolerances permit less precise registration.

The important feature for all combinations of aperture l2 and pin means 14 is that portions of the edge of the aperture 12 be shaped for registering with the pin means 14 to prevent lateral movement of the sheet and that clearance edges 22 by provided to enable the] holding strip 16 to deflect to concentrate tension in the separation region when the pin means 14 is forced against the holding strip 16 upon the operation of the feed means 32. Reliable feeding and clean, consistent separation in the separation region is also improved by providing that the aperture 12 be symmetrical about an axis 20 which is perpendicular to the registration edge 10.

Referring to FIG. 8, the clearance edges 22 are extended into slits 95 past the base edge 96 of the triangular-shaped aperture 12, and thereby define a flap 97' which may deflect without tearing when the answer sheets are positioned on pin means, such as the pin 14. This construction enables the size of the aperture 12 to be smaller in relation to the size of the pin 14, thereby assuring better registration of the answer sheet with the test grading device.

What is claimed is:

1. A set of answer sheets for use with a test grading device of the type wherein stacked answer sheets are held by pin means in a position for scanning of answer indication areas placed upon each answer sheet, and wherein said scanned answer sheets are fed seriatim with a predetermined force from said stack, each of the answer sheets being of a predetermined thickness and having a registration edge;

printed answer indication areas of a predetermined configuration placed upon the sheet in a prescribed relationship to the registration edge; and

an aperture positioned in a prescribed relationship to the answer indication areas and positioned in a prescribed relationship to and closely adjacent the registration edge,

the aperture edge and the registration edge defining a holding strip of varying width between the aperture and the registration edge,

the narrowest portion of the holding strip defining a separation region of a predetermined width between the aperture and the registration edge, and

two portions of the aperture edge in common with the holding strip most remote from and on opposite sides of the separation region defining two clearance edges;

characterized by the feature that each said sheet is approximately 4 mils thick and has approximately a 22 mil wide separation region, and

the two clearance edges converge toward each other toward the registration edge in directions which enable the holding strip to deflect to concentrate tension in the separation region when the holding strip of a said registered sheet is forced against a said pin means with said predetermined force.

2. A set of answer sheets according to claim 1, in which the aperture is centered along the registration edge of each sheet, characterized by the feature that the aperture is an isoceles triangle with a vertex adjacent the separation region, with a base of 0.5 inches parallel to the registration edge and with a height of approximately 0.18 inches.

3. A set of answer sheets according to claim 1, in which each answer sheet has an average smoothness of 1 12 Sheffield units.

4. A set of answer sheets according to claim 1, in which each answer sheet has a stiffness of approximately 2.05 Taber stiffness units.

5. A set of answer sheets according to claim 1, in which each registration edge is a smooth edge, such as the type of edge obtained when cutting paper with a sharpened guillotine cutter or sharpened slitter cutter, in contrast to the type of edge obtained by cutting paper with a dull slitter cutter or a dull guillotine cutter.

6. A set of answer sheets according to claim 5, in which each answer sheet has an average smoothness of H2 Sheffield units and a stiffness of approximately 2;05 Taber stiffness units.

7. A set of answer sheets according to claim 1, characterized by the feature that each answer sheet contains two registration edges, positioned answer indication areas on each side of the sheet, and two apertures correlated to the two registration edges.

A set of answer sheets according to claim 7, in

which each registration edge is a smooth edge such as the type of edge obtained when cutting paper with a sharpened guillotine cutter or sharpened slitter cutter, in contrast to the type of edge obtained by cutting paper with a dull slitter cutter or a dull guillotine cutter; and in which each answer sheet has an average smoothness of 1 l2 Sheffield units and a stiffness of approximately 2.05 Taber stiffness units.

9. A set of answer sheets according to claim 1, wherein the separation region width is within a range of from 20 to 35 mils.

10. A set of answer sheets according to claim 1, wherein the aperture is iosceles triangular-shaped with the base edge of the triangle parallel to the registration edge, characterized by the feature that the clearance edges extend into slits beyond the base edge. and thereby define a flap.

11. A method of preparing a set of answer sheets for use with a. test grading device of the type wherein' stacked answer sheets are held by pin means in a position for scanning of answer indication areas placed upon each answer sheet, and wherein said scanned answer sheets are fed seriatim with a predetermined force from said stack, which method comprises printing answer indication areas of predetermined configuration on 4 mils thick sheets; and cutting each sheet in a prescribed relation to the answer indication areas to form a registration edge and an aperture, with the aperture positioned in a prescribed relationship to the answer indication areas and in a prescribed relationship to and closely adjacent the registration edge, so that a holding strip of varying-width is defined between the aperture and the registration edge, with two portions of the aperture edge in common with the holding strip most remote from and on opposite sides of the separation region defining two clearance edges which converge toward each other toward the registration edge in directions which enable the holding strip to deflect to concentrate tension in the separation region when the holding strip of a said registered sheet is forced against a said pin means with said predetermined force, and with the narrowest portion of the holding strip defining a separation region ofapproximately 22 mils between the aperture of the registration edge.

Claims

1. A set of answer sheets for use with a test grading device of the type wherein stacked answer sheets are held by pin means in a position for scanning of answer indication areas placed upon each answer sheet, and wherein said scanned answer sheets are fed seriatim with a predetermined force from said stack, each of the answer sheets being of a predetermined thickness and having a registration edge; printed answer indication areas of a predetermined configuration placed upon the sheet in a prescribed relationship to the registration edge; and an aperture positioned in a prescribed relationship to the answer indication areas and positioned in a prescribed relationship to and closely adjacent the registration edge, the aperture edge and the registration edge defining a holding strip of varying width between the aperture and the registration edge, the narrowest portion of the holding strip defining a separation region of a predetermined width between the aperture and the registration edge, and two portions of the aperture edge in common with the holding strip most remote from and on opposite sides of the separation region defining two clearance edges; characterized by the feature that each said sheet is approximately 4 mils thick and has approximately a 22 mil wide separation region, and the two clearance edges converge toward each other toward the registration edge in directions which enable the holding strip to deflect to concentrate tension in the separation region when the holding strip of a said registered sheet is forced against a said pin means with said predetermined force.

3. A set of answer sheets according to claim 1, in which each answer sheet has an average smoothness of 112 Sheffield units.

6. A set of answer sheets according to claim 5, in which each answer sheet has an average smoothness of 112 Sheffield units and a stiffness of approximately 2.05 Taber stiffness units.

8. A set of answer sheets according to claim 7, in which each registration edge is a smooth edge such as the type of edge obtained when cutting paper with a sharpened guillotine cutter or sharpened slitter cutter, in contrast to the type of edge obtained by cutting paper with a dull slitter cutter or a dull guillotine cutter; and in which each answer sheet has an average smoothness of 112 Sheffield units and a stiffness of approximately 2.05 Taber stiffness units.

10. A sEt of answer sheets according to claim 1, wherein the aperture is iosceles triangular-shaped with the base edge of the triangle parallel to the registration edge, characterized by the feature that the clearance edges extend into slits beyond the base edge and thereby define a flap.

11. A method of preparing a set of answer sheets for use with a test grading device of the type wherein stacked answer sheets are held by pin means in a position for scanning of answer indication areas placed upon each answer sheet, and wherein said scanned answer sheets are fed seriatim with a predetermined force from said stack, which method comprises printing answer indication areas of predetermined configuration on 4 mils thick sheets; and cutting each sheet in a prescribed relation to the answer indication areas to form a registration edge and an aperture, with the aperture positioned in a prescribed relationship to the answer indication areas and in a prescribed relationship to and closely adjacent the registration edge, so that a holding strip of varying width is defined between the aperture and the registration edge, with two portions of the aperture edge in common with the holding strip most remote from and on opposite sides of the separation region defining two clearance edges which converge toward each other toward the registration edge in directions which enable the holding strip to deflect to concentrate tension in the separation region when the holding strip of a said registered sheet is forced against a said pin means with said predetermined force, and with the narrowest portion of the holding strip defining a separation region of approximately 22 mils between the aperture of the registration edge.