US3755657A

US3755657A - Scanning finger for electromechanical punch card scanner

Info

Publication number: US3755657A
Application number: US00184258A
Authority: US
Inventors: F Kunz
Original assignee: Individual
Current assignee: Individual
Priority date: 1971-09-27
Filing date: 1971-09-27
Publication date: 1973-08-28
Anticipated expiration: 1990-08-28

Abstract

An adjustable scanning finger for electromechanical punch card scanners has a resilient element which is urged into contact with a microswitch actuator upon sensing movement of the rigid finger. Adjustment is carried out by means of a set screw.

Description

United States Patent 1191 Kunz Au 28, 1973 [54] SCANNING FINGER FOR 2,475,307 7/1949 Brand et al. 235/6111 c ELECTROMECHANICAL PUNCH C ARD' 3,030,465 4/1962 Roeser 200/ 153 T SCANNER FOREIGN PATENTS OR APPLICATIONS Inventor: y y Kunz, Mafmorveien 5 1,467,245 12/1966 France 200/153 T Oslo, Norway [22] Filed: Sept. 27, 1971 Primary Examiner-Thomas A. Robinson [2]] App] No 184 258 Attorney-Dexter N. Shaw et al'.

[52] US. Cl 235/61. C, 200/153 T [57] I ABSTRACT 7f 9 An adjustable scanning finger for electromechanical 235/61 B 61 H punch card scanners has a resilient element which is urged into contact with a microswitch actuator upon [56] Reierences Cited sensing movement of the rigid finger. Adjustment is UNITED STATES PATENTS Lund 200/153 T carried out by means of a set screw.

5 Claims, 3 Drawing Figures SCANNING FINGER FOR ELECTROMECHANICAL PUNCH CARD SCANNER The present invention relates to a scanning finger for electromechanical punch card scanners, which scanning finger in cooperation with apassing punch card actuates as associated stationary micro switch by contact with a button on said switch.

Various scanning fingers are known but all of them have the disadvantage that they need readjustment due to wear or deformation after some time. The working stroke of the switch button is often very small, e.g. approximately 1 mm, and the known fingers thus need a most accurate adjustment to give the finger in cooperation with the passing punch card a stroke large enough to actuate the switch, but not large enough to deform or wedge any of the parts.

Scanning fingers needing constant inspection and readjustment and even replacement of parts, however, are unsuitable in a controlling apparatus controlling important production processes. If the scanning finger fails to function correctly, machinery as well as material to be processed might be badly damaged in addition to the resulting loss pf production.

The object of the invention is thus to provide a scanning finger securing an especially safe actuation to the micro switch for a long time without any need of readjustment.

This object is achieved according to the invention by a scanning finger of the above mentioned kind which is characterized in that the rigid finger member is pro vided with a resilient element which upon movement of the finger member is brought into contact with the switch button for actuation of said button at the sarrle time as the resilient element is deformed to some extent.

Due to the resilient element being deformed to some extent when actuating the switch, the finger will thus not perform a well defined working stroke but adapts itself to the working stroke of the micro switch. This adaptability secures actuation of the switch even after long use and wear, since inaccuracies which would otherwise cause failure, are compensated for by the adaption of the resilient element.

Further objects and features of the present invention will appear from the following description of an embodiment shown in the drawings, where FIG. I shows an elevation of a scanning finger according to the invention,

FIG. 2 shows an elevation of the rigid finger portion according to FIG. 1, and

FIG. 3 shows a section along theline the line A in FIG. 1 in a larger scale.

According to this preferred embodiment the scanning finger comprises a rigid, plate shaped finger member l, which is provided with a projection 2 for scanning punch cards and a hole 3 in its other end so as to be pivoted in a stationary frame or the like. The finger member may e.g. be manufactured by blanking out of a sheet material e.g. of metal.

A rigid arm 4 is pivoted in the rigid member and provided with an elongated recess wherein the finger member lies. Said arm 4 is pivoted to the finger member 1 by the aid of a through pin 5. In the present case the arm 4 thus has the shape of a two-armed lever. Said arm may preferably be manufactured by injection moulding of plastic.

In one end the arm 4 has a projection 6. Between said projection which is provided with a lug (not shown), and a recess 7 in the finger member having a lug 8 a helical spring 9 is arranged and controlled by said lugs.

The projection 6 is provided with a head 10 on top. When the finger is activated said head 10 is brought in contact with and will push in the button of a micro switch not shown).

The other end of the arm 4 is provided with a projection 11 with a through setscrew 12 serving for adjustment of the inclination of the arm relative to the finger member, or the distance of the head 10 from the micro switch button respectively.

As indicated in FIG. 2, there are two sets of recesses (7,8,5',7,8, and 5") for the desired arrangement of the arm in one of two positions on the finger member, as seen in the longitudinal direction of the finger member. Due to this arrangement it is possible to provide two series of micro switches, the breadth of the micro switch being larger than the total breadth of the scanning finger but smaller than the breadth of two scanning fingers.

The shown and preferred embodiment represents an especially simple, inexpensive and reliable solution, where any normal wear of deformation of the scanning system is compensated for due to the fact that the arm 4 is pivotal relative to the finger member 5 against a spring force produced by the spring 9. When the scanning system is mounted, an adjustment is made by the aid of the set screw 12. Further adjustment is superfluous for the reasons mentioned above. The scanning finger according to the invention has been subjected to tests corresponding to approximately 60 years of usage without any we'ar worth mentioning being formed. Failure did not occur.

Even though the scanning finger according to the preferred embodiment consists of a rigid finger member and a rigid arm pivoted on said finger member with a tensioned spring arranged between said members, it is obviously within the scope of the present invention to shape the scanning finger in various manners, the essential feature of the invention being that the rigid finger is provided with a resilient element causing the actuation of the switch.

I claim:

1. A scanning finger pivotable from a supporting frame for sensing irregularities in an irregular surface and for moving a switch arm in response thereto, the position of said switch arm being dependent on the angular position of said scanning finger with respect to said frame as determined by said irregularities, said scanning finger comprising a rigid finger member which is pivotable on said supporting frame and which has a sensing projection for riding over said irregular surface, a rigid arm carried by and pivotable on said finger member, an actuating head on said rigid arm for contacting and moving said switch arm, and spring means acting between said finger member and said rigid arm resiliently in a direction to urge said actuating head against said switch arm when said sensing projection is disposed on a raised portion of said irregular surface, said spring means being progressively deflected as one of said irregularities causes said switch arm to move downwardly from said raised portion.

2. The scanning finger of claim 1, comprising adjustable means for limiting the maximum angle of pivot of said rigid arm with respect to said rigid finger member,

said adjustable means being accessible to adjustment when said irregular surface is positioned to engage said sensing projection.

3. An assembly of two adjacent scanning fingers according to claim 1 in which each said finger member comprises at least two pivot means each adapted to enable pivoting of said arm relative to said finger member, each said finger member also comprising at least two spring-retaining means each corresponding to a different one of said pivot means and positioned at the same distance from its corresponding pivot means, said spring means on one finger being retained between said arm and said finger member by one of said springretaining means and said arm being pivotally supported on said finger member by the corresponding one of said pivot means, said spring means on the other finger being retained between said arm and said finger member by the other of said spring-retaining means and said other arm being pivotably supported on said finger member by the other of said pivot means, whereby said arms are pivotably and resiliently mounted to permit smaller lateral spacing between said adjacent scanning fingers in said assembly than the width of the switch arms contacted by the heads of said finger assembly.

4. A scanning finger for an electromechanical punched card scanner, said scanning finger being pivotably mounted in cooperative relation with a passing punched card to actuate an associated stationary microswitch by contactwith a button on the said switch, comprising a rigid finger member and an adjustable resilient element mounted thereon which, upon movement of the finger member onto said punched card, is

brought into contact with the said switch button and pushes it so as to actuate the said switch simultaneously with the resilient element being moved to a small extent about its point of pivot in an opposite direction relative to the movement of said button; said resilient element comprising a rigid arm pivoted on said rigid finger member, a tensioned spring member arranged between said finger member and said arm and a set-screw engaging said rigid arm and bearing against said finger member to limit the angular displacement of said arm with respect to said finger member, said set-screw providing for adjustment of the exact actuation of said microswitch upon a given displacement of the scanning finger by a punched card.

5. A scanning finger according to claim 4, characterized in that said rigid arm is a two-armed lever, said spring member being mounted at the one end and said set-screw at the other end of said lever, said rigid arm being pivotable relative to said rigid finger member about either of two possible positions on the said finger member, said finger member being provided with two mutually displaced and identical sets of lugs and holes, each set consisting of one lug and one hole and each set corresponding to one single set on the rigid arm, the latter set consisting of one lug and a hole through said arm, each of said holes providing space for a pin mean to provide for the pivoting of said arm relative to said rigid finger member, and said lug on said arm and either one of said two lugs on said finger member providing for the securing of said helical spring.

Claims

2. The scanning finger of claim 1, comprising adjustable means for limiting the maximum angle of pivot of said rigid arm with respect to said rigid finger member, said adjustable means being accessible to adjustment when said irregular surface is positioned to engage said sensing projection.

3. An assembly of two adjacent scanning fingers according to claim 1 in which each said finger member comprises at least two pivot means each adapted to enable pivoting of said arm relative to said finger member, each said finger member also comprising at least two spring-retaining means each corresponding to a different one of said pivot means and positioned at the same distance from its corresponding pivot means, said spring means on one finger being retained between said arm and said finger member by one of said spring-retaining means and said arm being Pivotally supported on said finger member by the corresponding one of said pivot means, said spring means on the other finger being retained between said arm and said finger member by the other of said spring-retaining means and said other arm being pivotably supported on said finger member by the other of said pivot means, whereby said arms are pivotably and resiliently mounted to permit smaller lateral spacing between said adjacent scanning fingers in said assembly than the width of the switch arms contacted by the heads of said finger assembly.

4. A scanning finger for an electromechanical punched card scanner, said scanning finger being pivotably mounted in cooperative relation with a passing punched card to actuate an associated stationary microswitch by contact with a button on the said switch, comprising a rigid finger member and an adjustable resilient element mounted thereon which, upon movement of the finger member onto said punched card, is brought into contact with the said switch button and pushes it so as to actuate the said switch simultaneously with the resilient element being moved to a small extent about its point of pivot in an opposite direction relative to the movement of said button; said resilient element comprising a rigid arm pivoted on said rigid finger member, a tensioned spring member arranged between said finger member and said arm and a set-screw engaging said rigid arm and bearing against said finger member to limit the angular displacement of said arm with respect to said finger member, said set-screw providing for adjustment of the exact actuation of said microswitch upon a given displacement of the scanning finger by a punched card.