US3831883A

US3831883A - Reel driving device for a web transporting apparatus

Info

Publication number: US3831883A
Application number: US00294709A
Authority: US
Inventors: D Easterly
Original assignee: Eastman Kodak Co
Current assignee: Eastman Kodak Co
Priority date: 1972-10-03
Filing date: 1972-10-03
Publication date: 1974-08-27
Anticipated expiration: 1991-08-27
Also published as: DE7335618U; GB1442680A; FR2201677A5

Abstract

A web transporting apparatus employs a reel driving spindle incorporating a friction clutch that is influenced by the radial load applied to the spindle. During normal operation of the apparatus, the winding torque that the spindle imparts to the reel is determined by the weight of the reel and the web wound thereon. During a rapid winding mode of operation, an additional radial load is applied to the spindle by a freely rotatable pressure roller or the equivalent to increase the torque transmitted to the reel through the spindle.

Description

linited States Patent [191 Easterly [451 Aug. 27, 1974 REEL DRIVING DEVICE FOR A WEB TRANSPORTING APPARATUS Donald 0. Easterly, Rochester, NY.

Eastman Kodak Company, Rochester, NY.

Filed: Oct. 3, 1972 Appl. No.: 294,709

Inventor:

Assignee:

US. or. 242/207, 242/67.5 rm. Cl. Bllb 15/32, G03b 1/04 Field of Search 242/75-75. 5 20 1;297,

References Cited UNITED STATES PATENTS 5/1941 Whittaker 242/207 9/1945 Underhill 242/206 3/1959 Moore i. 242/204 10/1964 Cisar 242/207 FOREIGN PATENTS OR APPLICATIONS France Germany Primary Examiner-Leonard 0. Christian Attorney, Agent, or Firm-Mr. J. Morrow [5 7] ABSTRACT A web transporting apparatus employs a reel driving spindle incorporating a friction clutch that is influenced by the radial load applied to the spindle. During normal operation of the apparatus, the winding torque that the spindle imparts to the reel is determined by the weight of the reel and the web wound thereon. During a rapid winding mode of operation, an additional radial load is applied to the spindle by a freely rotatable pressure roller or the equivalent to increase the torque transmitted to the reel through the spindle.

9 Claims, 4 Drawing Figures REEL DRIVING DEVICE FOR A WEB TRANSPORTING APPARATUS BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to web transporting mechanisms and, more particularly, to improved means for varying the torque delivered to drive the web during different modes of operation of the mechanism.

2. Description of the Prior Art It is known to use weight sensitive clutches to drive the spindles of web transporting mechanisms. For example, it is common to use such a clutch in motion picture projectors where film is intermittently advanced and then the film is wound upon a take-up spindle. While the clutches are effective to maintain a desired tension between the take-up reel and the film advancing mechanism during a normal projection, they are not normally effective to permit rapid driving of the film. Thus, it is frequently necessary to use auxiliary drive means to impart rotation to the spindle. The present invention is intended to eliminate the need for auxiliary drive means by assuring that the weight sensitive clutch provides the necessary torque for rapid winding of the film.

SUMMARY OF THE INVENTION An object of the present invention is to eliminate the necessity for an auxiliary drive means for a web transporting mechansim by providing more positive drive through an existing weight sensitive clutch means.

Another object of the present invention is to provide means for selectively changing the operation of a weight sensitive clutch between low torque and high torque conditions.

Still another object of the present invention is to provide a mechanism suitable for use in a motion picture projector having a weight sensitive clutch for driving a takeup spindle, the mechanism being suitable for selectively changing the condition of the clutch between low torque (slow winding mode of operation) and high torque (rapid winding mode of operation) conditions.

Briefly, these and other related objects are realized in accordance with the present invention by combining a weight sensitive spindle with a pressure roller or the equivalent that is movable into engagement with the driven member of the spindle for imparting a greater load thereto for increasing the torque transmitting capacity of the spindle clutch during a rapid winding mode of operation.

The invention, and its objects and advantages will become apparent in the detailed description of the preferred embodiment presented below.

BRIEF DESCRIPTION OF THE DRAWINGS In the detailed description of the preferred embodiment presented below, reference is made to the accompanying drawings, in which:

FIG. 1 is an exploded perspective view of an illustrative reel spindle mechanism according to the preferred embodiment of the present invention;

FIG. 2 is a partially cross-sectioned side elevational view of the mechanism depicted in FIG. 1;

FIG. 3 is a somewhat schematic end elevational view of the subject mechanism adjusted to its rapid winding or high torque mode of operation;

FIG. 4 corresponds to FIG. 3 but shows the illustrative mechanism adjusted to its slow winding or low torque mode of operation.

DESCRIPTION OF THE ILLUSTRATIVE PREFERRED EMBODIMENT Because motion picture projectors and other related apparatus are well known, the following description is directed in particular to those elements forming part of or cooperating directly with the present invention, elements not specifically shown or described herein being understood to be selectable from those known in the art.

Referring first to FIGS. 1 and 2 of the accompanying drawings, the illustrative take-up reel spindle will be seen to comprise a driving member 10 in coaxial supporting relation with a driven member 12. The driving member includes a shaft 14 rotatably supported in a bushing 16 carried by a frame plate 18. A pulley 20 is secured near one end of shaft 14 and is connected by an elastic belt 22 to a smaller pulley 24 on a motor 26. At its opposite end, the driving member is provided with a drum 28 having a cylindrical internal bore 30 concentric with its axis of rotation.

Driven member 12 comprises a cylindrical clutch head 32 that is rotatably received in the bore of drum 28 with the central section or hub 34 of the driven member projecting beyond the drum. A retaining collar 36 fits over drum 28 and is held in place by ears 38 which are bent over drum 28. The hub 34 of the driven member projects through an aperture 40 in collar 36, thereby maintaining the two

members

10 and 12 in relatively rotatable assembled relation to each other. Hub 34, in turn, extends through an opening 42 in the projector housing 44 and carries an arbor 46 adapted to support a film take-up reel 48. As is well known in the art, reel 48 is removably retained on the arbor by a spring loaded detent ball 50 or the equivalent and is engaged by a key or spline 52 to prevent relative rotation between the reel and the driven spindle member.

A selector lever 54 is pivotally supported to a spacer stud 56 on the frame plate by pivot screw 58 and extends through a slot 60 in the projector housing so that a handle portion 62 of the lever is accessible to the machine operator. A pressure wheel 64 is mounted to the selector lever in alignment with the hub of member 12 by means of an axle screw 66 threaded into a spacer stud 68 which is secured to the lever. Preferably, the pressure wheel is provided with a resilient surface 70, but as this feature is directed only to quiet operation it is not essential to the functioning of the mechanism.

A coil spring 72 is tensioned between spacer stud 68 of lever 54 and an anchoring stud 74 mounted to the projector housing by suitable means such as a screw 76. Because of the positioning of anchoring stud 74, pivot screw 66 and spacer stud 68 on lever 54, spring 72 exerts a detent or off-center influence on the selector lever to maintain it either in an inoperative or disengaged position (as shown in FIG. 4) or in its operative or engaged position (as shown in FIGS. 1-3). When lever 54 is in its inoperative position, which is defined by the abutment of lever 54 against end surface 78 of slot 60, pressure wheel 64 is removed from engagement with the spindle. When the lever is in its operative position, however, the wheel is urged radially against the hub 34 of driven member 12 by spring 72 and lever 54 remains a spaced distance from the end surface 80 of slot 60.

During the normal projection mode of operation, lever 54 is located in its inoperative position and motor 26 drives spindle member continuously in the direction in which the corresponding rotation of reel 48 causes a film strip 82 to be wound thereon. Because the driven member of the spindle is rotatable relative to the driving member, the winding torque imparted to the reel is transmitted through the spindle only by the frictional engagement between drum 28 of the driving member and clutch head 32 of the driven member. The amount of friction developed between those two clutch elements is, in turn, related to the radial force or load exerted on the driven member by the reel and the film strip wound thereupon. Since the effect of this force at the friction surfaces is accentuated by the cantilevered relation of the reel to the clutch elements, the initial torque transmitting capacity of the spindle is determined primarily by the weight of the reel, and the winding torque imparted to the reel increases as additional film is wound thereon. This results in a more uniform tension on the film than would result if the winding torque remained constant. During the projection mode of operation, the driving member rotates considerably faster than the driven member and the film tension is maintained such that damage does not occur to the film and the operation of the film advancing mechanism remains undisturbed.

To initiate the rapid winding mode of operation, lever 54 is moved to its operative position and the film advancing mechanism is disabled, either manually or by means or a coordinating mechanism operated by the selector lever. Because the radial force or load exerted on member 12 by pressure wheel 64 is substantially greater than the similar force previously attributable to the weight of the reel, the torque transmitting capacity of the spindle is substantially increased. At this time there is little or no relative movement between the drive member 10 and the driven member 12. Consequently, the reel is now driven in the same direction as before but with relatively high speed and torque to perform the rapid winding operation. After a desired amount of film has been wound onto the reel, the return movement of the selector lever to its inoperative position restores the subject mechanism to its original mode of operation.

The invention has been described in detail with partiaular reference to an illustrative preferred embodi ment thereof, but it will be understood that variations and modifications can be effected within the spirit and scope of the invention.

I claim:

1. Apparatus for winding a web material into a roll, the apparatus having a frame, drive means supported by the frame for supplying a driving torque, clutch means including a driving element coupled to the drive means and a driven element coupled to the driving element to receive and transmit torque from the driving element as a function of a force applied to the driven element, said driving and driven elements of said clutch means being rotatably about an axis, means coupled to the driven element of the clutch means for supporting the web material such that it may be wound into a roll,

and force applying means supported by said frame, said force applying means comprising:

a. a lever pivotally supported by said frame for movement between first and second positions; and

b. a circular member rotatably supported by said lever and positionable by said lever to (l) a first position when said lever is in its first position wherein said member is in engagement with said driven element of said clutch means and is effective to apply a force to said driven element of said clutch means in a direction substantially perpendicular to said axis, and to (2) a second position when said lever is in its second position wherein said member is out of engagement with said driven element of said clutch means.

2. In apparatus for winding a web material into a roll, the apparatus having a frame, drive means supported by said frame for supplying a driving force in one direction, friction clutch means including a driving element coupled to said drive means and a driven element frictionally coupled to said driving element to receive and transmit torque from said driving element, and means coupled to said driven element of said clutch means for supporting said web material such that it may be wound into a roll, the improvement comprising:

force applying means supported by said frame for adjusting the torque transmitted from the driving element to the driven element while the drive means supplies the driving force in said one direction, said force applying means being adjustable between (1) a first condition wherein a first driving torque is transmitted from said driving element to said driven element, said first driving torque being a function of the friction coupling between said driving element and said driven element and of the force supplied to said driven element of said clutch means by the weight of the roll of web material, and (2) a second condition wherein said force applying means is effective to apply an additional force to said driven element of said clutch means to increase the friction coupling between the driving element and the driven element such that a second and larger driving torque is transmitted from said driving element to said driven element.

3. In apparatus as set forth in claim 2 wherein said driving and driven elements of said clutch means and said web supporting means are rotatable about an axis and wherein said force' applying means when in its second position is effective to apply a force to said driven element of said clutch means in a direction substantially perpendicular to said axis.

4. In apparatus as set forth in claim I wherein said force applying means further comprises a spring member coupled to said frame and said lever in an offcenter manner to hold said lever alternatively in its first or second positions and to urge said circular member against said driven element of said clutch member when said lever is in its first position.

5. In combination with a reel spindle comprising a rotatively powered driving member and a reel supporting driven member supported by said driving member in co-axial relation thereto by a frictional clutch device adapted to transmit torque from said driving member to said driven member in proportion to a first friction producing force exerted on said driving member by the weight of a reel supported on said driven member and the weight of the material wound onto said reel, the improvement comprising an adjustable force increasing member comprising a freely rotatable wheel movable between a disengaged position spaced from said driven member and an engaged position wherein said wheel engages said driven member for selectively applying a second friction producing force to said driven member to substantially increase the amount of torque frictionally transmittable through said clutch device from said driving member to said driven member and to the reel supported thereby.

6. The invention defined by claim 5 wherein said wheel is positioned with respect to said driven member to bear radially against said driven member when said wheel is in its engaged position.

7. In combination with a reel spindle comprising a rotatably powered driving member and a reel supporting driven member supported by said driving member in co-axial relation thereto by frictional clutch device adapted to transmit torque from said driving member to said driven member in proportion to a first friction producing force exerted on said driven member by the weight of a reel which is supported on said driven member in a cantilever relation and the weight of the material wound onto said reel, the improvement comprising an adjustable force increasing member for selectively applying a second friction producing force to said driven member to substantially increase the amount of torque frictionally transmittable through said clutch device from said driving member to said driven member and to the reel supported thereby, said adjustable force increasing member being movable between a disengaged position spaced from said spindle and an engaged position wherein said force increasing member engages said driven member between said clutch device and said reel and applies said second friction producing force radially to said driven member.

8. The invention defined by claim 7 wherein said force applying member comprises a freely rotatable wheel movable edgcwise between its disengaged position and its engaged position, said driven member including a cylindrical surface engageable by the periphery of said wheel between said clutch device and said reel when said wheel is adjusted to its engaged position.

9. The invention defined by claim 8 including spring means urging said wheel radially against said cylindrical surface of said driven member when said wheel is in its engaged position.

Claims

1. Apparatus for winding a web material into a roll, the apparatus having a frame, drive means supported by the frame for supplying a driving torque, clutch means including a driving element coupled to the drive means and a driven element coupled to the driving element to receive and transmit torque from the driving element as a function of a force applied to the driven element, said driving and driven elements of said clutch means being rotatably about an axis, means coupled to the driven element of the clutch means for supporting the web material such that it may be wound into a roll, and force applying means supported by said frame, said force applying means comprising: a. a lever pivotally supported by said frame for movement between first and second positions; and b. a circular member rotatably supported by said lever and positionable by said lever to (1) a first position when said lever is in its first position wherein said member is in engagement with said driven element of said clutch means and is effective to apply a force to said driven element of said clutch means in a direction substantially perpendicular to said axis, and to (2) a second position when said lever is in its second position wherein said member is out of engagement with said driven element of said clutch means.

2. In apparatus for winding a web material into a roll, the apparatus having a frame, drive means supported by said frame for supplying a driving force in one direction, friction clutch means including a driving element coupled to said drive means and a driven element frictionally coupled to said driving element to receive and transmit torque from said driving element, and means coupled to said driven element of said clutch means for supporting said web material such that it may be wound into a roll, the improvement comprising: force applying means supported by said frame for adjusting the torque transmitted from the driving element to the driven element while the drive means supplies the driving force in said one direction, said force applying means being adjustable between (1) a first condition wherein a first driving torque is transmitted from said driving element to said driven element, said first driving torque being a function of the friction coupling between said driving element and said driven element and of the force supplied to said driven element of said clutch means by the weight of the roll of web material, and (2) a second condition wherein said force applying means is effective to apply an additional force to said driven element of said clutch means to increase the friction coupling between the driving element and the driven element such that a second and larger driving torque is transmitted from said driving element to said driven element.

3. In apparatus as set forth in claim 2 wherein said driving and driven elements of said clutch means and said web supporting means are rotatable about an axis and wherein said force applying means when in its is effective to apply a force to said driven element of said clutch means in a direction substantially perpendicular to said axis.

4. In apparatus as set forth in claim 1 wherein said force applying means further comprises a spring member coupled to said frame and said lever in an off-center manner to hold said lever alternatively in its first or second positions and to urge said circular member against said driven element of said clutch member when said lever is in its first position.

8. The invention defined by claim 7 wherein said force applying member comprises a freely rotatable wheel movable edgewise between its disengaged position and its engaged position, said driven member including a cylindrical surface engageable by the periphery of said wheel between said clutch device and said reel when said wheel is adjusted to its engaged position.