Roll type sheet material feeding apparatus

A sheet material feeding apparatus of a roll type includes a main feed roll and an auxiliary roll adapted to cooperate with the main roll to feed a sheet material in a clamped state on a step-by-step basis. The main roll is mounted on an output shaft of an indexing drive unit to be intermittently rotated in one direction. The auxiliary roll is supported swingably toward and away from the main roll. An adjusting mechanism is provided for adjusting the clamping force applied to the sheet material by the auxiliary roll. A release mechanism is provided for releasing the auxiliary roll from the cooperation with the main roll.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to a roll type feeding apparatus for feeding 
intermittently a sheet-like blank material to a processing station on a 
step-by-step basis. More particularly, the invention concerns a roll type 
feeding apparatus which includes a main feed roll and a counterpart or 
auxiliary clamp roll for feeding intermittently a strip-like sheet 
material to one or more work stations such as metallic molds in a 
selective manner and which is suited to be incorporated in automated 
manufacturing machines or other machine tools. 
2. Description of the Prior Art 
The hitherto known sheet material feeding apparatus of the type described 
above in which a combination of a one-way clutch and a brake or a 
combination of a rotating cam and a cam follower for converting a 
continuous rotation input to an intermittent rotation output for driving 
intermittently the feeding roller suffer from many shortcomings. For 
example, it is difficult, not to say impossible, to feed a strip-like 
blank material stepwise by a predetermined quantity with a reasonable 
accuracy due to backlash in a gear train, a dimensional tolerance involved 
in implementing the cam and cam follower mechanism. The feeding operation 
may not be carried out at a high speed because jamming or deformation of 
the sheet material being stepwise fed will be then possibly involved. 
Troublesome and time consuming procedures are required for adjusting the 
feeding apparatus for different sheet materials having different 
thicknesses. Further, it has been impossible to vary a quantity of sheet 
material to be fed through a single feeding step in a stepless manner 
without interrupting operation of the feeding apparatus as well as 
associated tool or tools. 
SUMMARY OF THE INVENTION 
Accordingly, an object of the present invention is to provide a roll type 
feeding apparatus for feeding a strip-like material intermittently, i.e. 
on a step-by-step basis which is evaded from difficulties and 
inconveniences of the hitherto known feeding apparatus such as described 
above. 
Another object of the invention is to provide a sheet material feeding 
apparatus of roll type which is capable of feeding a strip-like sheet 
material intermittently by a predetermined quantity with an enhanced 
accuracy even in a high speed operation without involving jamming, 
deformation or the like undersirable phenomena. 
Still another object of the invention is to provide a roll type feeding 
apparatus which can be adjusted in a much facilitated manner so as to 
accommodate different thicknesses of various sheet materials to be fed. 
A further object of the invention is to provide a sheet material feeding 
apparatus of roll type in which the quantity of sheet material to be fed 
through a single feeding step can be varied in a stepless manner without 
requiring interruption in operation of the feeding apparatus. 
According to a general aspect of the invention, there is provided a roll 
type feeding apparatus including an indexing drive means having an input 
shaft rotated continuously and an output shaft rotated intermittently in 
one rotation direction, a main roll mounted on the output shaft to be 
rotated together with the output shaft, an auxiliary roll adapted to 
cooperate with the main roll thereby to feed a sheet material in a state 
clamped between the main roll and the auxiliary roll, a pair of supporting 
panels each pivotally mounted at one end thereof on a housing of the 
feeding apparatus so as to be swingable in a direction orthogonal to the 
axis of the main roll and adapted to swing the auxiliary roll toward or 
away from the main roll in dependence on the swinging movement of the 
supporting panels, and adjusting means for adjusting the swinging movement 
of the auxiliary roll, the adjusting means including spring means for 
biasing the supporting panels so that the auxiliary roll is urged to move 
toward the main roll, and a cam rod rotatably supported in the housing and 
operatively connected to both of the paired supporting panels thereby to 
swing the supporting panels simultaneously against the urging direction of 
the biasing spring upon rotation of the cam rod. 
In a preferred embodiment of the invention, the adjusting means further 
includes a pair of release cams operatively connected to the input shaft 
of the indexing drive apparatus and disposed each adjacent to each end of 
the auxiliary roll, and a pair of release links each connected to each of 
the supporting panels, each of the release links including a first arm 
having one end pivotally connected to the associated supporting panel at a 
position adjacent to the free end portion of the panel and extending to a 
position adjacent to the pivotally mounted location of the panel and 
having a cam follower at an intermediate portion to be engageable with the 
associated one of the release cams, and a second arm having one end 
articulated to the other end of the first arm and extending transversely 
to the first arm, a release control member connected to the other ends of 
the second arms of both of the release links and adapted to selectively 
engage and disengage the cam followers to and from the release cams by 
swinging the first arms through the second arms. 
The above and other objects, novel features and advantages of the invention 
will become more apparent from the following description of preferred 
embodiments of the invention. The description makes reference to the 
accompanying drawings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
Referring to FIG. 1 which shows a roll type feeding apparatus according to 
an embodiment of the invention, the feeding apparatus comprises an 
intermittent or indexing drive apparatus denoted generally by reference 
numeral 3 and including an input shaft adapted to be rotated continuously 
in one direction and an output shaft 2 adapted to be intermittently 
rotated in one direction, a main roll 4 mounted on the output shaft 2 to 
be rotated together with the shaft 2, an auxiliary roll 5 disposed so that 
the axis thereof extends in parallel with the axis of the main roll 4 and 
adapted to cooperate therewith for feeding a sheet material in a clamped 
or pinched manner, and a pair of supporting panels 6 and 7 disposed at 
positions adjacent to both ends of the auxiliary roll 5, respectively. 
Referring to FIG. 2 in combination with FIG. 1, the supporting panel 6 has 
one end portion which is pivotally mounted on a housing 8 of the roll type 
feeding apparatus at a position 9 (FIG. 2) so that the panel 6 can be 
swung in the direction orthogonal to the axis of the main roll 4. There 
are disposed on the supporting panel 6 four bearings 10 at such positions 
that the associated end portion (right end portion as viewed in FIG. 1) of 
the auxiliary roll 5 is circumferentially enclosed and supported by the 
four bearings 10, as can be seen clearly from FIG. 2. The supporting panel 
or plate 7 is constructed and arranged in the substantially same manner as 
the supporting panel or plate 6, whereby the other end portion (left end 
portion as viewed in FIG. 1) of the auxiliary roll 5 is rotatably 
supported through cooperation of four bearings 11. In this manner, the 
auxiliary roll 5 is rotatable about the longitudinal axis thereof and 
additionally movable toward and away from the main roll 4 in dependence on 
the swinging movement of the supporting panels 6 and 7 about the pivotally 
supporting point 9. As will become apparent as description proceeds, the 
supporting panels 6 and 7 are interlocked to each other so that swinging 
or rotation of the panel 6 for a predetermined angular distance in the 
clockwise direction as viewed in FIG. 2, for example, is always 
accompanied by the corresponding rotation or swinging of the other 
supporting panel 7 in the clockwise direction. The swinging or rotation of 
the supporting panels 6 and 7 is adjusted by an adjusting apparatus 12 
(FIG. 2) composed of a clamp adjusting mechanism 12A and a release 
adjusting mechanism 12B, as will be described below. 
As is clearly shown in FIG. 2, the supporting panel 6 is constantly biased 
by a spring 13 in the counterclockwise direction in which the auxiliary 
roll 5 is urged toward the main roll 4 and has a stopper portion 6a which 
is formed at the right side of the panel 6 and bears against a top surface 
of an adjusting block 14. The supporting panel or plate 7 is also biased 
in the counterclockwise direction by a spring and has a stopper portion 
which bears against an adjusting block in the same manner as the 
supporting panel 6, although not shown in the drawing. The adjusting 
blocks 14 for the supporting panels 6 and 7 are mounted on the housing 8 
(FIG. 1) so as to be movable in the direction orthogonal to the axes of 
the rolls 4 and 5, i.e. in the vertical direction as viewed in FIG. 2. 
Each of the adjusting blocks 14 is formed with a cylindrical through-hole 
16 having the axis extending orthogonally to the plane of the associated 
supporting panel 6 or 7 and adapted to be inserted therethrough a single 
cam rod 15. 
Referring to FIG. 3, the cam rod 15 is constituted by an eccentric rod 
having an enlarged cam portion 15b integrally formed in an eccentric 
relation to the rotation axis 15a of the cam rod 15. The cam rod 15 is 
rotatably supported in the housing 8 at both ends thereof, while the 
eccentric cam portion 15b is inserted through the cylindrical through-hole 
16 formed in each of the adjusting blocks 14 which are disposed adjacent 
to the associated supporting panels 6 and 7, respectively. In this way, 
the peripheral surface of the eccentrically enlarged portion 15b of the 
cam rod 15 constitutes a camming surface, while the inner cylindrical 
surface of the through-hole 16 constitutes a cam follower surface. Thus, 
upon rotation of the cam rod 15, both of the adjusting blocks 14 are 
caused to move concurrently in the vertical direction as viewed in FIG. 2, 
as the result of which the auxiliary roll 5 is moved toward or away from 
the main roll 4. More specifically, assuming that the adjusting blocks 14 
are moved upwardly (as viewed in FIG. 2) against the biasing force of the 
spring 13 under camming rotation of the cam rod 15, the supporting panel 6 
as well as the supporting panel 7 are caused to swing in the clockwise 
direction as viewed in FIG. 2, resulting in that the auxiliary roll 5 is 
moved away from the main roll 4. When the adjusting blocks 14 are caused 
to move downwardly starting from the raised position described above, the 
supporting panels 6 and 7 are rotated in the counterclockwise direction 
under the biasing forces exerted by the associated springs 13, whereby the 
auxiliary roll 5 is returned to the original position adjacent to the main 
roll 4 as shown in FIG. 2. 
The biasing springs 13, the adjusting blocks and the cam rod 15 constitute 
the clamp adjusting mechanism 12A mentioned hereinbefore which serves to 
vary the inter-axial distance between the axes of the auxiliary and the 
main rolls 4 and 5. More specifically, as the adjusting blocks 14 of both 
the supporting panels 6 and 7 is moved upwardly (as viewed in FIG. 2) in 
dependence on the rotation of the cam rod in one direction, the 
inter-axial distance between the auxiliary and the main rolls 4 and 5 is 
progressively increased, as the result of which the clamping force applied 
to the sheet material pinched between the rolls 4 and 5 is correspondingly 
decreased. In this way, it is possible to adjust properly the clamping 
force applied to the sheet material being fed by adjusting rotation of the 
cam rod 15 so that the inter-axial distance between the rolls 4 and 5 can 
be selected in consideration of the spring force of the spring 13, the 
thickness of the sheet material or the like factors. It should be 
mentioned that the maximum inter-axial distance between the rolls 4 and 5 
attainable by the rotation of the cam rod 15 must be sufficiently large to 
allow freely the supply as well as extraction of the sheet material to or 
from the paired rolls 4 and 5. 
In the case of the embodiment being described, the cam rod 15 constituted 
by the eccentric cylindrical rod is inserted rotatably into the adjusting 
blocks 14 provided respectively for the supporting panels 6 and 7. 
However, it will be appreciated that the adjusting blocks 14 may be 
omitted by adopting such modified arrangement in which the supporting 
panels are formed with respective cam follower surfaces and directly swung 
by the cam rod 15 having a corresponding camming surface. In FIG. 2, 
reference numeral 33 denotes a mounting rod for the biasing spring 13 
mounted on each of the adjusting blocks 14, and 34 denotes a nut for 
supporting the spring 13 and simultaneously serving to adjust the biasing 
force thereof. It should be noted that a manipulating rotatable handle 
(not shown) is mounted on the cam rod 15 at one end thereof. 
The auxiliary or counterpart roll 5 is constituted by a tubular hollow roll 
which encloses therein an intermediate portion of the input shaft 1 of the 
indexing drive apparatus 3 which will be hereinafter described in detail. 
A release cam 17 (FIGS. 1 and 2) is mounted on the input shaft 1 at a 
position adjacent to the right end of the counterpart roll 5 as viewed in 
FIG. 1. As is shown in FIG. 2, a release link 19 is pivotally mounted at 
one end thereof on the supporting panel 6 in the vicinity of the free end 
or side portion (left side as viewed in FIG. 2) thereof as indicated by 
20. The release link 19 is composed of a first arm 22 which extends 
transversely to a point located in the vicinity of the pivotal mounting 
point 9 of the supporting panel 6 and has a cam follower 21 mounted at a 
middle portion, and a second arm 24 which has one end pivotally connected 
to the free end of the first arm 22 and extends transversely relative to 
the first arm (in the substantially vertical direction as viewed in FIG. 
2). The cam follower roll 21 is adapted to engage with the release cam 17. 
A second release link similar to the link 19 is provided also for the 
supporting panel 7, wherein a cam follower 35 mounted on a first arm 36 of 
the second release link is adapted to engage a release cam 18 mounted on 
the input shaft at a position adjacent to the left end of the auxiliary or 
counterpart roll 5, as can be seen from FIG. 1. The second arms of both 
the release links are connected to a single release control member 25 at 
lower ends thereof as viewed in FIG. 2. 
The control member 25 is constituted by an eccentric rod of a configuration 
similar to that of the cam rod 15 shown in FIG. 3 and supported rotatably 
in the housing 8. The enlarged eccentric portion of the release control 
rod is inserted through circular through-holes 26 formed, respectively, in 
the lower end portions of the second arms 24 of both the release links. A 
rotation handle (not shown) is mounted on the control rod 25 at one end 
thereof. With the arrangement described above, when the eccentric control 
rod member 25 is rotated in the circular through-holes 26 formed in the 
second arms 24, the first arms 21 and 36 of the first and the second 
release links are rotated in the clockwise or counterclockwise direction 
about the respective pivotal studs 20 as viewed in FIG. 2 in accordance 
with the rotation of the control rod 25. Assuming, for example, that the 
first arm 22 is caused to swing in the counterclockwise direction from the 
position shown in FIG. 2, the cam follower 21 is disengaged from the 
release cam 17, while at the same time the first arm 36 of the release 
link provided at the side of the supporting panel 7 is swung in the 
counterclockwise direction. As the result, the cam follower 35 is moved 
away from the release cam 18. On the other hand, when the first arms 22 
and 36 are rotated in the clockwise direction, the state shown in FIG. 2 
is restored in which the cam followers 21 and 35 are in engagement with 
the respective release cams 17 and 18. 
When the cam followers 21 and 35 are engaged with the associated release 
cams 17 and 18, respectively, the first arms 22 and 36 are intermittently 
and alternately rotated in the clockwise and the counterclockwise 
directions about the respective pivotal connections or articulations 23 
(FIG. 2) during continuous rotations of the release cams 17 and 18 formed 
integrally with the input shaft 1. In more particular, only when a 
protrusion 17a of the release cam 17 is engaged with the cam follower 21 
during the rotation of the cam 17, the first arm 22 is caused to swing in 
the clockwise direction about the link articulation 23. Upon occurrence of 
the pivotal movement of the first arm in the clockwise direction, the 
pivotal movement is transmitted to the supporting panel 6 through the 
pivotally connecting stud 20, whereby the supporting panel 6 is caused to 
swing in the clockwise direction against the biasing force of the spring 
13 about the pivotally mounting stud 9. At that time, the adjusting block 
14 stands stationarily. When the protrusion 17a of the release cam 17 
comes to engagement with the cam follower 21, a similar protrusion (not 
shown) of the release cam 18 is simultaneously brought into engagement 
with the cam follower 35, as the result of which the supporting panel 7 is 
pivotally moved in the same direction as the supporting panel 6. 
Consequently, the auxiliary or counterpart roll 5 supported by the panels 
6 and 7 at both ends thereof is moved away from the main roll 4. When the 
cam followers 21 and 35 are progressively disengaged from the protrusions 
formed in the associated release cams 17 and 18 upon further rotation 
thereof, the supporting panels 6 and 7 as well as the associated first 
cams are caused to swing in the counterclockwise direction under the 
biasing force of the spring 13, whereby the counterpart roll 5 is moved 
toward the main roll 4. The movement of the auxiliary roll 5 is stopped 
when the stopper portions such as 6a of the supporting panels bear on the 
associated adjusting blocks 14. 
The release link 19, the eccentric control rod member 25, release cams 17 
and 18 and so forth described above constitutes the release mechanism 12B 
mentioned hereinbefore which serves to release the sheet material from the 
state pinched between the main roll 4 and the counterpart roll 5 in 
dependence on the operation of the intermittent drive apparatus 3. The 
release adjusting mechanism 12B is particularly advantageous when the 
indexing drive apparatus is operated with a rather poor accuracy. More 
specifically, the main roll 4 is adapted to be intermittently rotated in 
one direction together with the output shaft 2 of the indexing drive 
apparatus 3. As the consequence, the sheet material pinched between the 
rolls 4 and 5 is also intermittently fed in one direction. In case the 
operating accuracy of the indexing drive apparatus is not of a degree to 
be satisfied, the magnitude of the intermittent rotation of the output 
shaft 2 and hence the feeding quantity of the sheet material for a single 
advance becomes inaccurate. In general, the roll type feeding apparatus of 
this kind is employed as a drive source for feeding a blank sheet material 
intermittently (i.e. on a step-by-step basis) by a predetermined length 
sequentially to a metallic mold which is usually provided with stopper 
means brought into contact with the leading edge of the sheet material 
when a predetermined quantity of the sheet material has been supplied. 
Accordingly, when the actually supplied quantity of the sheet material has 
exceeded the predetermined quantity due to inaccurate operation of the 
output shaft 2, there arises a danger that deformation of distortion may 
be produced in the sheet material due to the action of the stopper means 
provided for the metallic mold. This problem is solved by the release 
mechanism 12B described above. Namely, the supporting panels 6 and 7 are 
swung to move the counterpart roll 5 away from the main roll 4 thereby to 
release the sheet material from the clamped or pinched state and stop the 
feeding thereof, when the input shaft 1 as well as the release cams 17 and 
18 has been rotated for an angular distance corresponding to a feeding 
quantity of the sheet material preselected for a single feeding step. In 
this manner, the feeding quantity of the sheet material during a single 
feeding step can be controlled accurately even when the magnitude of 
rotation of the output shaft 2 exceeds a predetermined value. If it is 
desired that the release mechanism 12B is to be inoperative, this can be 
easily accomplished by merely rotating the control member 25 thereby to 
move the second arms 24 upwardly from the position shown in FIG. 2. In 
this case, the inter-axis distance between the rolls 4 and 5 is maintained 
at a distance adjusted by means of the clamp adjusting mechansim 12A. 
In the case of the illustrated embodiment, it is assumed that the feeding 
apparatus is provided with both the clamp ajusting mechanism 12A and the 
release adjusting mechanism 12B. However, it will be readily appreciated 
that the release adjusting mechanism 12B may be omitted. Further, although 
the control rod 25 is employed for moving simultaneously the second arms 
for the supporting panels 6 and 7 for the same distance in the vertical 
direction, it is self-explanatory that the release adjusting mechanism 12B 
may be operated easily and appropriately by using other type cam 
combination. 
As is shown in FIG. 1, the main roll 4 is constituted by a double-walled 
tubular roll. The mounting of the main roll 4 on the output shaft 2 is 
effected by snugly fitting a slanted surface 4a' formed in the inner 
tubular wall 4a on a complementarily slanted portion 2a formed in the 
output shaft 2. With this arrangement, it is possible to mount securely 
the main roll 4 on the output shaft for simultaneous rotation by 
displacing main roll 4 to the left as viewed in FIG. 1 thereby closely 
engaging the slanted surfaces 4a' and 2a to each other by means of a 
clamping bolt 28. In FIG. 1, reference numeral 29 denotes a flexible 
coupling, 30 denotes a rotation transmitting plate, and 31 denotes a 
radial spring for supporting the rotation transmitting plate 30 through a 
bearing 32. The radial spring 31 is constituted by a sleeve imparted with 
a slight elasticity in the radial direction. 
The intermittent drive or indexing drive apparatus 3 includes a first cam 
assembly (composite cam) 40 mounted on the input shaft 1 to be 
continuously driven, a first turret assembly (or cam follower assembly) 
mounted fixedly on a turret shaft 41 and adapted to swing in dependence on 
the rotation of the first cam assembly 40, an intermediate or follower 
shaft 37 extending substantially in parallel with the turret shaft 41 and 
the output shaft 2 mentioned hereinbefore and positioned in alignment with 
the follower shaft 37, an interlocking mechanism 43 for opertively 
connecting the turret shaft 41 and the follower shaft 37 to each other and 
a clutch mechanism 44 for operatively disengageably coupling the follower 
shaft 37 and the output shaft 2 to each other. 
Referring to FIGS. 1 and 4, the first turret assembly 42 is in an inverted 
V-like form and has a pair of legs 42a and 42b which are provided with cam 
follower rolls 4c and 4d at respective lower or free ends thereof. On the 
other hand, the first cam assembly 40 is constituted by a pair of cam 
discs 40a and 40b. It will be noted that the turret assembly 42 and the 
first cam assembly 40 are so disposed relative to each other that the cam 
follower roll 42c rests on the peripheral camming surface of the cam disc 
40a while the cam follower roll 42d follows the rotation of the cam disc 
40b. In this manner, when the cam assembly 40 is rotated continuously in 
one direction together with the input shaft 1, the first turret assembly 
42 is caused to swing with the turret shaft 41 being rotated in an 
oscillating manner as indicated by an arrow A in FIG. 4. The swinging 
movement of the first turret assembly 42 will of course depend on the 
geometrical configuration or profile of the cam discs 40a and 40b. It 
should be mentioned here that the mechanism for converting a rotating 
movement into a swinging movement or oscillatory rotation with the aid of 
a combination of cam means and a turret assembly of the type described 
above has been hitherto known by itself as referred to sometimes as the 
swinging drive unit or the like. Further, the arrangement such that the 
cam follower rolls disposed rotatably at the free ends of the bifurcated 
legs of the inverted V-like member are brought in engagement with the 
associated cam members which are adapted to be rotated together as an 
integral unit has also been know in terms of the conjugated cam mechanism. 
In the case of the illustrated embodiment now being described, by virtue 
of the adopting of the so-called conjugated cam mechanism, undesirable 
backlash can be positively prevented from occurrence by maintaining the 
cam discs 40a; 40b and the cam follower rolls 42c; 42d in the mutually 
engaged state under a preset pressure which can be controllably 
established by decreasing the distance between the input shaft 1 and the 
turret shaft 41, whereby vibrations and generation of noises in the 
operation of the indexing drive apparatus can be effectively suppressed 
even at a high operation speed. Additionally, a high indexing accuracy can 
be attained in the operation of the indexing drive apparatus. 
Referring to FIGS. 5 and 6 in combination with FIG. 1, the interlocking or 
coupling unit 43 mentioned hereinbefore includes a first swingable arm 46 
which extends in a direction substantially orthogonal to the axis of the 
turret shaft 41 (FIG. 6) and has one end connected fixedly or integrally 
to the turret shaft 41. A slide member 45 is disposed longitudinally 
slidably in the first swing arm 46 for the purpose described hereinafter. 
The interlocking unit 6 further comprises a second swing arm 47 extending 
substantially in parallel with the first swing arm 46 and fixedly fitted 
on the follower shaft 37 at in inner end thereof, a connecting rod 11 
pivotally connected to a free end of the second swing arm 47 and to the 
slider member 45, a spherical or crown gear 49 provided at the first swing 
arm 46, and a spur gear 50 mounted rotatably at a stationary portion of a 
housing 8 (FIG. 1) and adapted to mesh with the crown gear 49. It should 
be noted that the spherical gear or crown gear 49 is so mounted as to be 
swingable about the axis 51 of the turret shaft 41 (FIGS. 6 and 7a) 
together with the first swing arm 46 as indicated by an arrow A in FIGS. 6 
and 7a and additionally rotatable about the axis 53' extending 
orthogonally to the turret axis 51 in a plane containing the axis 51 of 
the turret shaft 41 and the axis 52 of the first swingable arm 46. The 
crown gear 40 has a semi-spherical surface having the center of curvature 
at the intersection O of the turret axis 51 and the rotation axis 53' and 
formed with a number of external gear teeth 49' which extend linearly and 
arcuately along the direction of the rotation axis 53'. The crown gear 49 
is meshed with the spur gear 50 which has gear teeth 50' extending 
linearly in the same direction as the arcuate teeth 49' of the crown gear 
49 (refer to FIG. 7 in particular). With such arrangement of the crown 
gear 49 and the spur gear 50, swinging of the crown gear 49 about the 
turret axis 51 in a horizontal direction as indicated by the arrow A as 
viewed in FIG. 6 will bring about a corresponding movement of the teeth 49 
relative to the teeth 50' of the spur gear 50 in the same direction as the 
swinging of the crown gear 49 about the axis 51. Reference is made to a 
phantom line position in FIG. 7b. On the other hand, when the spur gear 50 
is rotated about the center axis 50" thereof (FIGS. 5 and 7), the crown 
gear 49 is caused to rotate about the rotation axis 53'. In FIGS. 1 and 5, 
reference numeral 55 denotes an electric motor for driving the spur gear 
50 through a drive belt 54 running around a pulley of the shaft 56 on 
which the spur gear 50 is fixedly mounted. 
Referring to FIGS. 5 and 6, a driving gear 57 is fixedly mounted on the 
rotatable shaft 53 of the crown gear 49 and meshes with a driven gear 58 
which in turn is threadedly mounted on a threaded rod 59 disposed in a 
guide groove formed in the first swing arm 46 for the slider member 45. It 
will be noted that the gear 58 is supported stationarily relative to the 
arm 46. The free end of the threaded rod or shaft 59 is fixedly connected 
to the slider member 45. With this arrangement, when the motor 55 is 
operated to drive the spur gear 50 thereby to rotate the crown gear 44 
together with the rotation shaft 53 thereof, the driven gear 58 is rotated 
by the driving gear 57, whereby the threaded shaft 59 and hence the slider 
member 45 are displaced in a corresponding direction along the axis 52. 
The purpose of providing the slider member 45 in the manner described 
above is to allow an angular swing range of the second arm 47 to be varied 
relative to that of the first swing arm 46, as will be elucidated 
hereinafter. In FIGS. 5 and 6, reference numeral 60 denotes a pivot pin 
secured to the slider member 45 and serving for pivotally connecting an 
enlarged end portion 61 of the connecting rod 48 to the slider member 45. 
The other end of the connecting rod 48 is also pivotally connected to the 
second swingable arm 47 in a similar manner (refer to FIG. 5). 
Next, reference is made to FIGS. 8 to 10 in combination with FIG. 1. The 
inner end portion (right end portion as viewed in FIGS. 1 and 8) of the 
follower shaft 37 is reduced in diameter and rotatably lodged within a 
sleeve portion 2' formed integrally in the inner end portion (left end 
portion as viewed in FIGS. 1 and 8) of the output shaft 2. The follower 
shaft 37 and the output shaft 2 are adapted to be disengageably coupled to 
each other through a clutch unit designated generally by reference numeral 
44. The clutch unit 44 comprises a second cam assembly 62 fixedly secured 
to or formed integrally with the input shaft 1 (FIGS. 1 and 8) and a 
second turret assembly 63 which is disposed so as to enclose the sleeve 
portion 2' at the coupling location of the follower and output shafts 37 
and 2. There are provided between the sleeve portion 2 and the second 
turret assembly 63 a clutch sleeve 64, a brake sleeve 65 and first to 
third groups of needle rollers 66 to 68 which are arranged in the manner 
shown in FIG. 8 The configurations and structures of the second cam 
assembly 62 and the second turret assembly 63 may be similar to these of 
the first cam assembly 40 and the first turret assembly 42. 
More particularly, referring to FIGS. 1 and 8, the clutch sleeve 64 is 
inserted between the sleeve portion 2' and an inner peripheral wall 63a of 
the mounting hole formed in the second turret assembly 63 to thereby 
define first and second annular gaps 69 and 70 between the sleeve portion 
2' and the second turret assembly 63, while the brake sleeve 65 is fitted 
around the end portion of the output shaft 2 adjacent to the clutch sleeve 
64 to define a third annular gap 71 in cooperation with the inner 
peripheral wall 63a of the mounting hole of the second turret assembly 63. 
The clutch sleeve 64 is fixedly secured to a shaft enclosure wall portion 
8a of the housing 8 at the left end thereof by means of screws, while the 
brake sleeve 65 is fixedly secured to a similar enclosure wall portion 8b 
at the right end thereof as viewed in FIGS. 1 and 8. As can be best seen 
from FIGS. 9 and 10, the first to third groups of needle rollers 66, 67 
and 68 described above are accommodated within the first, second and the 
third annular gaps 69, 70 and 71, respectively, with the individual needle 
rollers being arrayed closely to one another in each of the annular gaps. 
The inner peripheral wall 63a of the mounting hole formed in the second 
turret assembly 62 as well as the outer peripheral surface 64a of the 
clutch sleeve 64 are each shaped in the form of a substantially similar 
equilateral polygon in cross-section (hexagonal shape in the case of the 
illustrated embodiment), wherein each side of the polygon is profiled in a 
form of Archimedes' spiral, as can be seen from FIG. 9. It is assumed now 
that the second turret assembly 63 is rotated for a predetermined angle 
from the position at which the inner wall 63a of the second turret 
assembly 63 is aligned with the outer periphery 64a of the clutch sleeve 
64 in respect of the cross-sectional configuration (i.e. the position 
shown in FIG. 9) to the position shown in FIG. 9a in which the 
cross-sectional profiles in concern are mutually deviated in the 
peripheral direction from the aligned position. In this state shown in 
FIG. 9a, the inner peripheral wall 63a of the second turret assembly 63 
will press the second group of needle rollers 67 against the clutch sleeve 
64 which will then be pressed radially inwardly. As the consequence, the 
sleeve portion 2' of the output shaft 2 is additionally pressed radially 
inwardly against the outer peripheral surface of the follower shaft 37 
through the first group of the needle rollers 66. In this manner, the 
follower shaft 37 is brought into a tight frictional engagement with 
the-output shaft 2 at the location of the sleeve 2', whereby the follower 
shaft 37 and the output shaft 2 are in the position to be rotated together 
as the unitary combined shaft. On the other hand, when the second turret 
assembly 63 is rotated in the opposite direction indicated by an arrow B 
in FIG. 9 for the predetermined angle, the aligned position between the 
second turrret assembly 63 and the clutch sleeve 64 is restored, wherein 
the follower shaft 37 is idly rotatable within the sleeve portion 2' of 
the output shaft 2. Thus, drive power transmission from the follower shaft 
37 to the output shaft 2 will not take place. 
With the terms "Archimedes' spiral" recited above, it is intended to mean a 
curve of which radius r varies at a constant rate as a function of a 
rotational angle .theta., i.e. the curve which can be mathematically 
expressed by r=K.theta. where K is a constant, as is illustrated in FIG. 
11. Although it has been found that both the inner wall of the second 
turret assembly 63 and the outer periphery of the clutch sleeve 64 should 
be preferably formed in a polygon having sides each in a form of the 
Archimedes' spiral, it will be appreciated that other various curved 
profiles may be made use of in place of the Archimedes' spiral to the 
substantially same effect. 
As can be seen from FIG. 10, the outer periphery 65a of the brake sleeve 65 
is also in a form of an equilateral polygon similar to that of the inner 
camming periphery 63a of the second turret assembly 63 with each side 
being profiled in a curve such as the Archimedes' spiral expressed by the 
formula r=K or the like. In this connection, it should be noted that the 
outer polygonal periphery 65a of the brake sleeve 65 is circumferentially 
displaced relative to the polygonal cam periphery 63a of the second turret 
assembly 63 (refer to the position shown in FIG. 10), when the latter is 
in a position aligned with the outer polygonal periphery 64a of the clutch 
sleeve 64 shown in FIG. 9. In the position shown in FIG. 10, the inner 
polygonal cam periphery 63a of the second turret assembly 63 will press 
the brake sleeve 65 radially inwardly through the interposed needle 
rollers 68 of the third group, as the result of which the brake sleeve 65 
is enforcively brought into a frictional close engagement with the output 
shaft 2 to thereby lock the output shaft 2 in the non-rotatable state. In 
this manner, when the second turret assembly 63 and the clutch sleeve 64 
are in the position shown in FIG. 9 in which the follower shaft 37 is 
rotatable relative to the output shaft 2, the latter is positively 
prevented from being rotated by means of the brake sleeve 65. 
On the other hand, when the second turret assembly 63 and the clutch sleeve 
64 are brought to the position shown in FIG. 9 in dependence on the swing 
movement of the second turret assembly 63 at which position the follower 
shaft 37 is rotatably coupled to the output shaft 2, the polygonal cam 
periphery 63a of the second turret 63 is geometrically aligned with the 
outer polygonal periphery 65a of the brake sleeve 65, resulting in that 
the pressing force applied radially inwardly to the brake sleeve 65 is 
removed, whereby the output shaft 2 is allowed to rotate within the brake 
sleeve 65. In this way, the follower shaft 37 and the output shaft 2 are 
set to the position to be rotated together as an integral unit. In FIGS. 1 
and 8, reference numeral 72 denotes a needle bearing for assuring a smooth 
rotation of the follower shaft 37 relative to the output shaft 2. Further, 
it will be self-explanatory that the first to third needle roller groups 
66 to 68 serve also as the bearings for allowing smooth rotation of the 
follower shaft 37 and the output shaft 2. 
Now, description will be made on operations of the indexing drive apparatus 
3 of the structure described above. 
When the input shaft 1 and the first cam assembly 40 are rotated 
continuously in a given direction, the first turret assembly 42 is caused 
to swing under the camming action of the cam assembly 40, resulting in the 
oscillatory rotation of the turret shaft 41 and hence the swinging 
movement of the first swing arm 46 fixedly secured to the turret shaft 40 
(refer to FIGS. 1, 5 and 6). The swinging movement of the first swing arm 
46 is transmitted to the second swing arm 47 by way of the connecting rod 
48, whereby the follower shaft 37 fixedly connected to the second swing 
arm 47 is caused to oscillate in rotation. Further, since the second cam 
assembly 62 of the clutch apparatus 45 is rotated together with the input 
shaft 1 thereby causing the second turret assembly 63 to perform a 
corresponding swinging movement, the second turret assembly 63 and the 
clutch sleeve 64 will take alternately the positions shown in FIGS. 9 and 
9a, while the positional relationship between the second turret assembly 
63 and the brake sleeve 65 is varied concurrently. 
As described hereinbefore, at the position shown in FIG. 9a, the follower 
shaft 37 is rotatable together with the output shaft 2. To the contrary, 
at the position shown in FIG. 9, the output shaft 2 is held stationarily 
regardless of the rotation of the follower shaft 37. Accordingly, when 
arrangement is previously made such that the clutch apparatus 44 takes the 
operating state illustrated in FIG. 9 upon oscillatory rotation of the 
follower shaft 37 in one direction while taking the operating state 
illustrated in FIG. 9a upon oscillatory rotation of the follower shaft 37 
in the other direction, the output shaft 2 is caused to rotate 
intermittently only in the one direction. Such arrangement can be easily 
established by designing appropriately the geometrical or positional 
relationship between the first and the second cam assemblies 40 and 62. 
In the indexing or intermittently drive apparatus described above, it is 
possible to change the ratio of the swing angle of the second swing arm to 
that of the first swing arm simply by displacing the slider member 45 
(refer to FIGS. 5 and 6) in the first swing arm 46 along the axis 52. As 
can be seen from FIG. 6, the first swing arm 46 is adapted to swing about 
the center axis 51 of the turret shaft 41 which corresponds to the point O 
shown in FIG. 5. Consequently, when the slider memory 45 is displaced 
along the axis 52, the distance C between the above point O and a 
connecting point D (FIG. 5) of the first swing arm 46 and the connecting 
rod 48 will be correspondingly changed, whereby the angle .theta. between 
the axis 52 and the connecting rod 48 is changed correspondingly. Thus, 
the swing angle of the second swing arm 47 is changed for a predetermined 
angular displacement of the first swing arm 46, involving a corresponding 
variation in the rotation angle of the follower shaft 37 and hence the 
output shaft 2. 
The sliding movement of the slider member 45 can be effected by rotating 
the crown gear 4a by the motor 55 through the spur gear 50 to move the 
screw rod 59 in the axial direction 52 of the first swing arm 46 through 
the paired gears 57 and 58, as described hereinbefore. Further, the crown 
gear 49 is also caused to swing due to the swinging rotation of the turret 
shaft 41 as brought about by the continuous rotation of the first cam 
assembly 40. In this connection, it should be noted that meshing 
engagement between the crown gear 49 and the spur gear 50 provides no 
obstacle to the swinging movement of the first swing arm 46 because the 
teeth of crown gear 49 are able to move smoothly laterally relative to the 
teeth of the spur gear 50 in any swinging direction, as described 
hereinbefore. Of course, the displacement of the slider member 45 can be 
manually controlled by providing an appropriate handle instead of the 
motor 55. 
With the arrangement of the roll type feeding apparatus disclosed in the 
foregoing, a sheet material clamped or pinched between the main roll 4 and 
the counterpart or auxiliary roll 5 is fed intermittently or on a 
step-by-step basis through intermittent rotation of the output shaft 2 of 
the indexing drive apparatus 3 and hence of the main roll 4 in one 
direction, while rotating the input shaft 1 continuously. According to the 
teaching of the invention, the counterpart roll 5 is moved toward or away 
from the main roll 4 to set a sheet material to be fed in a clamped state 
or unclamped state merely through a simple manipulation of rotating 
correspondingly the cam rod 15 of the clamp adjusting mechanism 12A of the 
adjusting apparatus 12 shown in FIG. 2, whereby the procedures for 
supplying and extracting a sheet material to and from the paired rolls 4 
and 5 can be advantageously facilitated. Further, by adjusting rotation of 
the cam rod 15, the inter-axis distance between the rolls 4 and 5 can be 
varied to thereby adjust the clamping force applied to the sheet material 
pinched between the feeding rolls 4 and 5 in a simplified manner to an 
additional advantage. 
By virtue of the provision of the release adjusting mechanism 12B for the 
adjusting apparatus, the feeding of a sheet material can be carried out 
with an improved accuracy regardless of possible poor operation accuracy 
of the indexing drive apparatus 3 as described hereinbefore. Further, when 
the operation of the release adjusting mechanism 12B is not required or 
exerts adverse influence as in the case where a sheet material is 
successfully to be fed to different metallic molds for manufacturing 
different articles, the release adjusting mechanism 12B can be readily 
inhibited from operation through a simple manipulation of rotating the 
control rod member 25, which manipulation can be performed without 
requiring interruption in the operation of the feeding apparatus. 
In general, in order to assure an accurate transmission of the intermittent 
rotation of the output shaft 2 of the indexing drive apparatus 3 thereby 
to allow the feeding of a sheet material to be carried out accurately and 
rapidly through the main roll 4 and the counterpart auxiliary roll 5, it 
is required that both of the rolls 4 and 5 be implemented in a decreased 
weight to thereby reduce inertias of these rolls. In the case of the 
illustrated embodiment, such requirement is satisfactorily met by the 
tubular hollow structures of the rolls 4 and 5. Further, the structure in 
which the intermediate portion of the input shaft 1 of the indexing drive 
apparatus 3 is disposed within the counterpart hollow roll 5 with the 
release cams 17 and 18 being mounted thereon contributes to simplification 
and compactness of the overall structure of the release adjusting 
mechanism 12B. 
The structure of the indexing drive apparatus 3 described hereinbefore 
allows the output shaft 2 to be intermittently rotated with a high 
accuracy for rotating the main feed roll 4. The indexing drive apparatus 3 
brings about a great advantage as compared with the conventional indexing 
drive apparatus using a number of gears and susceptible to backlash and 
rattling. 
With the interlocking mechanism 43 of the arrangement described 
hereinbefore, it is possible to vary the magnitude of the intermittent 
rotation of the output shaft 2 and hence the feeding quantity of a blank 
sheet material in a stepless manner by varying the ratio of rotation angle 
of the second swing arm 47 to that of the first swing arm 46 through 
displacement of the slider member 45 along the axis 52. Refer to FIGS. 5 
and 6. Thus, the feeding apparatus incorporating the indexing drive 
apparatus 3 is advantageously suited for use in combination with an 
automated manufacturing machine or machines designed for manufacturing 
different articles or products either on a large or small scale basis. 
More specifically, by varying the rotation angle or oscillation manitude 
of the output shaft 2 and hence that of the main roll 4, the feeding 
quantity of the sheet material fed during a single feeding step can be 
correspondingly changed. Accordingly, when the type or kind of products is 
to be varied, the feeding quantity of the blank sheet material can be 
correspondingly changed, whereby the sheet material may be fed to various 
different machine tools located at different positions.