Transport mechanism

A transport mechanism for film cards having two rocker levers supported on a pivoting lever that can swivel around a shaft, with the rocker levers being capable of pivoting around a rocker lever shaft. The two rocker levers, in turn, support two opposite discs, one of which is driven by a motor. A gripping motion of the discs is brought about by provision of guide grooves located on the rocker levers, with each groove accommodating a stationary pin. Through provision of an intermediate carrier, the upper disc is fixed to the upper rocker lever in a manner that it can pivot around a horizontal axis which is at right angles to the rocker lever shaft. Therefore the upper disc can be tilted in the respective direction of transport.

BACKGROUND OF THE INVENTION 
This invention relates to a transport mechanism for transporting a film 
card (microfiche) or comparable object, guided between two straight 
guides, from one station to another, for example for transporting a film 
card from a film card holder to a film card magazine, having a feeder 
mechanism for gripping and transporting a film card or comparable object. 
Said feeder mechanism is positioned at the end of a straight guide where 
the transport is to be carried out and can be moved at right angles in 
relation to the film card or comparable object. The feeder mechanism has 
two discs which are able to rotate and to perform a pincer-wise motion 
towards the film card or comparable object and form an acuate angle in 
gripping position. At least one of said discs is provided with a motor, 
the direction of rotation of which can be reversed, according to 
co-pending U.S. patent application Ser. No. 541,583, now U.S. Pat. No. 
4,544,151. 
In the embodiment described in the U.S. Pat. No. 4,544,151, the discs are 
provided at one end of a relatively long lever. When these two levers 
pivot towards the film card, the discs approach each other, thus rendering 
it possible for the respective film card to be gripped and transported. As 
it is necessary that one of the discs tilt in the respective direction of 
transport at an inclined angle relative to the film card, one of the discs 
is mounted pivotably on the corresponding lever in a manner that renders 
it possible for the disc to tilt independently towards the respective 
direction of transport. 
The film cards or comparable objects which are to be transported with a 
transport mechanism are often of different thickness or undulated as a 
result of internal stress. With the mechanism such as discloses in the 
U.S. Pat. No. 4,544,151, such differences in the qualities of the objects 
to be transported make it necessary to optimize the entire mechanism for 
the respective application by appropriate dimensioning of the levers. That 
is to say, for different applications, strongly differing transport 
mechanisms have to be manufactured, which is uneconomical. 
SUMMARY OF THE INVENTION 
This invention is based on the primary object of refining the transport 
mechanism such as disclosd in the U.S. Pat. No. 4,544,151 in a manner that 
renders it possible for objects with different qualities to be transported 
reliably without or with merely minor alterations of the mechanism. 
This object is established according to the invention by provision of two 
rocker levers for locating the discs. Said rocker levers are mounted 
pivotably on a swivelling lever which can be moved at right angles in 
relation to the direction of transport. For purposes of control of the 
gripping motion performed by the discs each rocker lever is adjustably 
supported through a support pin eccentrically mounted on the frame through 
a screw, and a cooperating guide, in the form of a groove, at the ends of 
the levers pointing away from the discs. 
This design according to the invention makes for control of the gripping 
motion by the two guides. Therefore this motion can be influenced in a 
manner that affords optimal gripping and transport of the film cards to be 
transported. For the various applications, the position of the stationary 
pins can be adjusted, hence adjusting the entire transport mechanism with 
a relatively small effort. 
An additional advantage of the transport mechanism according to the 
invention rests with the fact that all its component parts can be combined 
in one assembly, hence eliminating the necessity of controlling levers at 
different positions in the apparatus the transport mechanism is intended 
for. Therefore an operational check of the transport mechanism can be 
carried out before it is installed in the respective apparatus. 
It is advantageous for the design to support the rocker levers on the 
swivelling lever by a mutual rocker level shaft. This makes it possible 
for the levers to cross each other in a pincer-wise motion. This, however, 
is not necessary as the gripping motion can be controlled as desired by 
the pin and guides. 
It is a preferred embodiment of the invention to support one of the discs 
on a carrier which is fixed to the respective rocker lever in a manner 
that makes possible for the carrier to tilt between two stops and around 
an axis at right angles in relation to the direction of transport. 
The transport mechanism such as disclosed in the U.S. Pat. No. 4,544,151 
featured one disc being capable of swivelling in the respective direction 
of transport. This feature, however, had the effect that the portions of 
the discs making contact with each other performed slightly different 
movements, resulting in the film cards being subjected to shearing forces 
and, as a consequence, in abrasion and loss of kinetic energy. These 
shortcomings are eliminated by the present invention. Even in the tilted 
position, the contours of the discs remain congruent, hence insuring that 
no relative velocities occur in the contact areas. 
As an effect of the gripping motion, the disc swivelled in the direction of 
transport tends to move back to a horizontal position. If, however, the 
carrier is retained against one of its stops by means of a spring, and a 
lifting magnet is employed for pivoting the carrier torwards the other 
stop, the disc can be forced to tilt, hence affording a more reliable 
transport of the film cards or comparable objects. 
The pin and guide arrangement is especially simple in its design when the 
ends of the rocker levers pointing away from the discs have one groove 
each, and when each groove accommodates a stationary pin. 
By providing the pins eccentrically on an adjustment screw, it is possible 
to adjust the gripping travel and the gripping plane. 
By designing the shape of the grooves to be initially horizontal and then 
to follow an inclined path, a result is achieved whereby the discs 
initially do not carry out a gripping motion while travelling from a 
lateral position to a position above the film cards or comparable objects. 
When regarding the two discs as separate jaws of a pair of tongues, one 
can say that this pair of tongues can reach above and below the film cards 
before it closes. 
The movement of the transport mechanism from a resting position to the 
transport area where the film card or comparable object is to be gripped 
is most easily achieved when the swivelling lever is retained in a resting 
position by means of a spring and when the transport mechanism features a 
lifting magnet for pushing the swivelling lever into an operating position 
of the two discs. 
In order to render it possible for film cards stored in a film card 
magazine to be gripped and transported by the transport mechanism 
according to the invention, it is necessary that the film card magazine 
posess a recess at one corner as disclosed in U.S. patent application Ser. 
No. 572,077, filed Jan. 19, 1984, and embodied herein by reference. The 
film cards are not guided in this area. This can result in the face edges 
of the film cards having different distances from one another in the area 
of said recess. By means of a separator having two separating surfaces 
with a slot therebetween, the film cards can be separated even in such 
event, so that one specific film card can be gripped and transported by 
the discs. 
In another preferred embodiment, the separator is made with the edge facing 
the film cards at an inclined angle with respect to the direction of 
transport, to thereby pick up the respective film card by the separator 
not from the front but farther to the back, close to the point where the 
film card is guided by the film card magazine. Therefore reliable gripping 
of the film cards is possible even when the front edges of the film cards 
make contact with each other. 
It is furthermore favorable that the separator be pretensioned in the 
direction of the film card or comparable object by means of a spring, that 
a separator cam rests against the rocker lever shaft and that the travel 
of the separator following the shaft is limited by means of elongated 
holes. This makes it possible for the separator to advance faster than the 
discs, separate the film cards and then come to a stop, so that the disc 
can travel farther in order to grip and transport the film cards.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
FIG. 1 shows a frame 1 supporting a pivoting lever 3 by means of a shaft 2. 
A tension spring 4, tensioned between the pivoting lever 3 and the frame 1 
keeps the pivoting lever 3 in front of the ram 5 of a lifting magnet 6. 
When the latter is excited, the pivoting lever 3 pivots from its resting 
position into an operating position counter-clockwise, that is towards the 
left in the drawing. 
On the other end of this pivoting lever 3 two rocker levers 8 and 9 are 
supported by means of a mutual rocker lever shaft 7. Further details on 
the design of these rocker levers 8 and 9 can best be taken from FIGS. 4 
and 5. FIG. 4 shows the upper rocker lever 9 as one component part, 
whereas in FIG. 5 the lower rocker lever is shown as one component part. 
In FIG. 4 a bore 10 is to be seen in the upper rocker lever 9 accommodating 
the rocker lever shaft 7 when mounted. The upper rocker lever 9 has a 
groove 11 at its right end in the drawing, the course of which moves from 
an initial horizontal direction towards a downward inclination. In 
addition the rocker lever 9 has two horizontal bores 12 and 13 into which 
a brace 14 illustrated in FIG. 3 can be inserted in a manner that it can 
swivel around a horizontal axis 15 which is at right angles in relation to 
the rocker lever shaft 7. 
As shown in FIG. 5, the lower rocker lever 8 also has a bore 16, hence 
being capable of also accomodating the rocker lever shaft 7. Also in 
correspondence with the upper rocker lever 9, the lower rocker lever 8 has 
a groove 17 at its left end in the drawing, the course of which is 
approximately horizontal initially, but then changes to an upward 
inclination. A disc 18 is positioned at the end of the rocker lever 8 
opposite the groove 17, with this disc being capable of being driven by a 
motor 19 in both directions of rotation. 
As shown in FIG. 3, a second disc 20 is supported on a carrier 14 on which 
it can rotate, the former not being driven by a motor and being positioned 
opposite the disc 18 when mounted. In order to force and limit the tilting 
of the carrier 14 on the rocker lever 9, the carrier 14 has a depending 
tab 21 to which further reference will be made later. 
For further explanation of the invention FIG. 6 be referred to in 
particular. First of all, a frame 1 can be seen having a pivoting lever 3 
supported on the shaft 2 as well as the rocker lever shaft 7 supporting 
the rocker levers 8 and 9. Two pins 22 and 23 reach into the grooves 17 
and 11 from opposite sides. These pins 22 and 23 are each mounted 
eccentrically on adjustment screws 25 and 26 with the latter mounted in 
the frame and capable of being turned. 
When turning these adjustment screws 25 and 26, the position of the pins 21 
and 22 can be changed, thereby adjusting the rocker levers 8 and 9. 
FIG. 7 illustrates the manner in which the carrier 14 tilts in relation to 
the rocker lever 9. One can see that the tab 21 passes through an opening 
26 of the rocker lever 8 and that it rests against the ram 27 of another 
lifting magnet 28. This lifting magnet 28 is fixed to the pivoting lever 
3. A tension spring 29, tensioned between the tab 21 and the pivoting 
lever 3, keeps the tab in direct contact with the ram 27. When the lifting 
magnet is excited, the ram 27 moves towards the left in the drawing, 
resulting in the carrier 14 tilting clockwise into the final position 
marked with a broken line in the drawing. 
The transport mechanism illustrated is designed for transporting film cards 
from a film card magazine to the film card holder or in the reverse 
direction. The film cards are not guided in the area where the transport 
mechanism can operate. Therefore the edges of the film cards facing the 
transport mechanism can be of irregular alignment or can even make direct 
contact with one another. This necessitates the use of a separator, the 
design of which is above all revealed in FIG. 8. 
The separator generally designated 30 is a basically flat component 
featuring two elongated holes 31 and 32, through which two screws 33 and 
34 reach in such a manner that the separator 30 can move towards the left 
in FIG. 8 as governed by the length of the elongated holes. In the resting 
position shown in the drawing the separator 30, can, however, not move 
towards the left, because a separator cam 35 rests against the rocker 
lever shaft 7. 
When the pivoting lever 3 swivels counter-clockwise, however, the separator 
30 initially follows this motion, since a tension spring 36 gives it 
pretension in this direction. Yet, before the pivoting lever 3 reaches its 
final position, the elongated holes 31 and 32 limit the further travel of 
the separator 30. The discs 18 and 20 illustrated in FIG. 1 can therefore 
move farther to the left in the drawing than the separator. 
The separating effect of the separator is brought about by a specially 
designed separating head 37. Between diverging surfaces 38 and 39 the 
separating head 37 has a slot 40 capable of taking up one individual film 
card. It is furthermore of importance for the proper functioning of the 
separator that the leading edge of the separator head 37 be at a slightly 
inclined angle in relation to the direction of transport as shown in FIG. 
6. The direction of transport is marked by an arrow in 42 in FIG. 6. This 
inclination of the leading edge 41 results in the film cards to be 
transported to be picked up and inserted into the slot 40 of the 
separating head 37 at the corner of the separating head most distant from 
the discs 18 and 20. 
The transport mechanism functions as follows: 
When a film card is to be transported, the pivoting lever 3 is made to 
pivot counter-clockwise through excitation of the lifting magnet 6. The 
rocker lever shaft 7 carries the rocker levers 8 and 9 towards the left in 
the drawing at the same time. The provision of the pins 22 and 23 and the 
grooves 11 and 17 results in the discs 18 and 20 minimally altering their 
relative distance, if at all, yet performing a relatively fast gripping 
motion towards the end of the travel of the pivoting lever 3, hence 
gripping the film card to be transported in a pincer-wise manner. The two 
discs 18 and 20 are driven by a motor 19, making it possible to obtain the 
desired transport motion. 
In accordance with the transport mechanism such as disclosed in the parent 
application, the disc 20 tilts into the respective direction of transport, 
with said disc being forced to tilt through excitation of the lifting 
magnet 28. 
Before the film card to be transported enters the gap between the discs 18 
and 20, the slot 40 of the separating head 37 grips over them, resulting 
in exact guidance of the respective film card at the point of time the 
discs 18 and 20 grip it. 
Referring to FIG. 9, the relative placement of the transport mechanism, 
generally designated by the numeral 50, with the other elements of the 
microfilm machine is shown. There is a film platform 51 which has two 
guides 52 and 53 on the opposite sides thereof. Guides 52 and 53 retain a 
film card 54 upon the film platform 51. The card is slidable in the 
direction of the arrow 55. A cassette 56 into which the film cards 54 can 
slide is arranged beside the film platform 51. Transport device 50 is 
disposed on one side of film platform 51 immediately in from of guide 53 
and in front of cassette 56.