US3487661A

US3487661A - Safety stop mechanism for straight bar knitting machine

Info

Publication number: US3487661A
Application number: US710212A
Authority: US
Inventors: Rudolph Anke
Original assignee: North American Rockwell Corp
Current assignee: Boeing North American Inc
Priority date: 1968-03-04
Filing date: 1968-03-04
Publication date: 1970-01-06
Anticipated expiration: 1987-01-06
Also published as: DE1909118A1; FR2003138A1

Description

Jan. 6, 1970 R. ANKEM 3,487,661

SAFETY STOP MECHANISM FOR STRAIGHT BAR KNITTING MACHINE Filed March 4, 1968 2 Sheets-Sheet 1 Jan. 6, 1970 R. ANKE 3,487,66

SAFETY STOP MECHANISM FOR STRAIGHT BAR KNITTING MACHINE Filed March 4, 1968 2 Sheets-Sheet 2 United States Patent 3,487,661 SAFETY STOP MECHANISM FOR STRAIGHT BAR KNITTING MACHINE Rudolph Anke, Reading, Pm, ass gnor, by mesne ass gnments, to North American Rockwell Corporation, Pittsburgh, Pa., a corporation of Delaware Filed Mar. 4, 1968, Ser. No. 710,212

Int. Cl. DiMb 35/10 U.S. Cl. 66--157 7 Claims ABSTRACT OF THE DISCLOSURE Safety stop means for a camshaft of a knitting machine, the safety stop means being operative to prevent rotation of the cam shaft in a direction reverse to the power operated direction thereof and being operative to permit reverse rotation of the camshaft during manual operation thereof.

BACKGROUND OF THE INVENTION Field of the invention escription of the prior art Heretofore straight bar or full-fashioned knitting machines were provided with a camshaft for operating the knitting elements of the machine, and means for driving the camshaft of the type disclosed in US. Patent No. 1,706,645, issued Mar. 26, 1929, the drive means including a handwheel shaft extending along the front of the machine and driven by a motor, a drive shaft driven from the handwheel shaft and gears connecting the drive shaft to the camshaft. Associated with the handwheel shaft was a brake or safety stop means of the type disclosed in US. PatentNo. 1,711,301, issued Apr. 30, 1929 which included manually operated means for activating the safety stop means to prevent reverse rotation of the shafts when the machine was conditioned for power operation and for inactivating the safety stop means to permit reverse rotation of the shafts by manual rotation of the handwheel shaft in the reverse direction.

More recently, in order to eliminate the constantly rotating handwheel shaft and to reduce the manual power required to rotate the shafts in the reverse direction when required the manual means was redesigned to include a jack shaft which was connected to and driven by the motor and driving connections between the jack shaft and drive shaft. The drive means also included a manually operated handwheel shaft extending from the front to the back of the machine, a worm on the handwheel shaft meshing with a worm wheel associated with the motor shaft, clutch members associated with the motor shaft and worm wheel and manually operated means for inactivating the clutch members for power operation of the machine and for activating the clutch members for manual operation of the machine by the handwheel shaft. The jack shaft was provided with safety stop means similar to that disclosed in said Patent No. 1,711,301 and manually operated means for activating the safety stop means to prevent reverse operation of the motor and shafts when the machine was conditioned for power operation and for inactivating the safety stop means to permit manual operation of the shafts in both the power operated and reverse directions.

When the safety stop means was associated with the handwheel shaft at the front of the machine and the stop means was inadvertently allowed to remain in active condition the operator was unable to exert sufficient force to overcome the braking force of the safety stop means to rotate the handwheel shaft in the reverse direction. However, when the safety stop means was associated with the manually operated worm and worm wheel and the safety stop means was inadvertently allowed to remain in active condition, sufficient manual force could be exerted through the worm and worm wheel to reverse the rotation of the shafts and smash the safety stop means.

SUMMARY OF THE INVENTION Briefly summarized the invention resides in the provision of safety stop means associated with the operating shafts of a straight bar knitting machine having both power means and manual means for operating the shafts. The manual operating means and safety stop means are controlled by common means to inactivate the manual operating means and activate the safety stop means to prevent reverse rotation of the shafts when the machine is conditioned for power operation and to activate the manual operating means and inactivate the safety stop means to permit the shafts to be manually rotated in both the power operated and reverse directions when the machine is conditioned for manual operation.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view taken transversely through a full-fashioned knitting machine showing the drive mechanism of the machine with means according to the invention incorporated therein;

FIG. 2 is a plan view on an enlarged scale of a portion of the mechanism of FIG. 1;

FIG. 3 is a view on an enlarged scale of a portion of FIG. 1; and

FIG. 4 is a cross-sectional view on an enlarged scale taken on the line and in the direction of the arrows 44 of FIG. 3.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG. 1 of the drawings there is shown a portion of 9. preferably multi-section full-fashioned knitting machine for knitting fabric blanks, such as for hosiery, sweaters and the like, the machine including a center frame 10, a back beam 11 and a front beam 12. The beams 11 and 12 and center and front beds (not shown) are secured to the center frames and end frames (not shown) to form the usual framework of the machine. Mounted in the center and end frames is a camshaft 15 having cams for operating needles and other elements required to form the fabric blanks and a drive shaft 16 having a gear 17 meshing with a gear 20 on the camshaft. The drive shaft 16 is driven by a link belt 21 or the like from a short jack shaft 22 rotatably supported in brackets, one of which is shown at 25 in FIGS. 3 and 4, which are secured to the back beam 11, and the jack shaft is in turn driven by a link belt 26 from a shaft 27 of an electric motor 30 carried on a base member 31 mounted in fixed position on the back beam 11 and front beam 12. The camshaft 15 is rotated by motor 30 through shafts 16 and 22 in a counterclockwise direction as indicated by the arrow in FIG. 1 and hereinafter referred to as the power operated direction.

The camshaft 15 is also adapted to be manually rotated both in the power operated direction and in the direction reverse thereto. The means for this purpose includes a shaft 32, which extends from the front to the back of the machine, from left to right as viewed in FIG. 1, the shaft 32 being rotatably mounted in a bracket 35 carried on one of the center frames and a bearing member 36 (FIG. 2). The bearing member 36 is secured by bolts 37 to a platelike bracket 40 which is in turn adjustably secured by bolts 41 to a bracket 42 mounted in fixed position on the back beam 11 (FIGS. 2 and 3). A worm 45 fixed on the right end of the shaft 32 is in meshing engagement with a worm wheel 46 having a hub portion rotatably mounted in a bore in the bracket 40'. The worm wheel is fixed against axial movement in the bore by engagement of the worm wheel with one face of the bracket and engagement of a plate 50 secured to the hub portion with the other face of the bracket (FIG. 2).

Secured on the end of the shaft 27 of the motor 30 is a clutch disc 51 having notches for receiving teeth of a clutch 52 mounted in an inner bore in the worm wheel 46. A key is fixed on the clutch sleeve for engagement in a keyway (not shown) in the inner bore of the worm wheel to cause the clutch sleeve to rotate with the worm wheel and permit axial movement of the clutch sleeve and the teeth thereon into and out of engagement with the clutch disc 51. For axially moving the clutch sleeve in the worm wheel, the clutch sleeve is provided with an annular groove 55 adapted to receive the ends of pins 56 carried in arms 57 of a forked end 58 of a lever 60 pivoted on a stud 61 carried in the bracket 42. An arm 62 of the lever 60 is connected by a universal joint 65 to one end of a rod 66, the rod extending toward the front of the machine from the arm for engagement in a vertically extending slot 67 in a bracket 70 secured to the front beam 12 (FIG. 1). A collar 71 on the rod 66 is adapted to engage in back of a stop finger 72 on the bracket to hold the rod when it is moved toward the left to the position of FIG. 1 to shift the clutch sleeve 52 into engagement with the clutch disc 51. The rod 66- is raised to disengage the collar 71 from the stop finger against the bias of a spring 75 connected between the rod and bracket 70 when the rod is to be moved toward the right from its position of FIG. 1 to turn lever 60 clockwise from its position of FIG. 2 to shift the clutch sleeve out of engagement with the clutch disc.

When the machine is to be power operated by the motor 30 the rod 66 is manually moved toward the right from its position of FIG. 1 to disengage the clutch sleeve 52 from the clutch disc 51 on the motor shaft 27. At this time the clutch sleeve 52 engages and closes a normally open switch 76 connected into the operating circuit of the motor to condition the operating circuit to permit the motor to be started and stopped under the control of pattern and manually operated means conventionally provided on the machine. Each time that the motor circuit is opened to stop the machine, during the period the machine is conditioned for power operation, the camshaft must be prevented from rotating in a direction reverse to its power operated direction in order to prevent damage to both the fabric forming elements of the machine and the fabric formed thereby.

Mechanisms of the type described have heretofore been employed and provide the environment for the instant invention which serves to prevent reverse rotation of the camshaft referred to above. In its preferred embodiment the present invention comprises safety stop or backstop means including an over-running roller clutch assembly 77 which is mounted on a sleeve 80 secured to the end of the jack shaft 22, the clutch assembly being positioned on the sleeve between an enlarged head portion 81 of the sleeve and a collar 82 fixed on the shaft 22 (FIG. 4). The clutch assembly 77, which is of a commercial type such as shown in Us. Patent No. 3,241,641, has an outer shell adapted to be secured in a bore 85, as by press fitting, in an outer sleeve 86. Mounted in the sleeve 86 and secured thereto for rotation therewith as by key 87 are first and second ratchets 9G and 91 of first and second means for controlling the operation of the clutch assembly 77. The teeth of the ratchet which are directed in one direction, are adapted to be engaged by a first pawl 92 pivotally mounted on a pin 95 carried in the bracket 25 to arrest the movement of the clutch assembly 77 to permit the shaft 22 to rotate freely in one direction relative the clutch assembly. The teeth of the ratchet 91, which are directed in a direction opposite to the direction of the teeth of ratchet 90, are adapted to be engaged by a second pawl 96 also pivotally mounted on the pin 95 to arrest the movement of the clutch assembly to cause the rollers of the clutch assembly to grip the sleeve and prevent rotation of the shaft 22 in the opposite direction. The

pawls

92 and 96 are positioned in side-by-side relationship on the pin 95 between a collar 97, secured to the pin by a set screw 100, and a shoulder 191 on the pin (FIG. 4) and the pawls are biased toward engagement with their ratchets by springs 102 connected between the pawls and a pin 105 in the bracket 25 (FIG. 3).

During operation of the machine by the motor the rod 66 is moved toward the right from the position of FIG. 1 to disengage the clutch sleeve 52 from the clutch disc 51 to inactivate the manually operated means and to close the switch 76 to condition the motor circuit and motor for power operation as hereinbefore set forth. Also at this time the

pawls

92 and 96 are engaged with the teeth of the

ratchets

90 and 91, respectively, to prevent rotation of the ratchets, outer sleeve 86 and the clutch assembly 77 with the shaft 22 as the latter is rotated by the motor in the power operated direction. Engagement of the pawls with their

respective ratchets

90 and 91 also causes the rollers of the clutch assembly 77 to grip the sleeve 80 and prevent reverse rotation of the shaft when the motor is stopped.

When the machine is to be manually operated, the rod 66 is moved to its position of FIG. 1 to shift the clutch sleeve 52 into engagement with the clutch disc 51 and to disengage the clutch sleeve from the switch 76 thereby permitting the latter to open and inactivate the motor operating circuit. The shaft 32 may then be rotated by a handwheel 106 secured to left end of the shaft 32 to turn the motor shaft 27 to operate the

shafts

15, 16 and 22 in the power operated direction. In order to also permit the shaft 32 to be turned to rotate the motor and shafts in the reverse direction, the pawl 96 must be disengaged from the ratchet 91. Thereafter, when the shaft 32 is turned to rotate the motor and shafts in the reverse direction the rollers of the clutch assembly 77 are moved into gripping engagement with the sleeve 86 to cause the sleeve and clutch assembly to rotate in the reverse direction with the shaft 22.

In order to disengage the pawl 96 from the ratchet 91 the pawl is provided with an arm 107 for engagement with one arm 110 of a lever 111 pivoted on a stud 112 carried by the bracket 74. The lever 111 has a second arm 115 for engagement with a finger 116 secured to lever 60 by screws 117 (FIG. 2). When therod 66 is moved to its position of FIG. 1 to condition the machine for manual operation, the finger 116 moves lever 111 clock wise to disengage the pawl 96 from the ratchet 91 to permit the clutch assembly 77 to rotate with shaft 22 when the motor and shafts are rotated in the reverse direction by the shaft 32.

It is believed to be obvious from the foregoing that when the power operated means is activated and the manual operating means is inactivated, the safety stop means is conditioned to permit rotation of the camshaft by the power operated means in the power operated direction and to prevent rotation of the camshaft in the direction reverse to the power operated direction. Furthermore, when the power operated means is inactivated and the manual means is activated, the safety stop means is conditioned to permit rotation of the camshaft by the manual operated means in both the power operated and reverse directions.

Of course, the improvements specifically shown and described by which the above described results are obtained, can be changed and modified in various ways without departing from the invention herein disclosed and hereinafter claimed.

I claim:

1. In a straight bar knitting machine having a camshaft, power means for operating said camshaft in one direction to form fabric on Said machine, manual means for operating said camshaft, and a control member movable from a first position to activate said power means to operate said camshaft and to inactivate said manual means to a second position to inactivate said power means and activate said manual means to operate said camshaft, the improvement including safety stop means associated with said camshaft, a first means for controlling the operation of said safety stop means during the operation of said camshaft in said one direction, a second means for controlling the operation of said safety stop means to control the operation of said camshaft in a direction reverse to said one direction, means for operating said second controlling means in said first position of said control member to condition said safety stop means to prevent operation of said camshaft in said reverse direction and means operated by said control member in said second position to operate said second controlling means to condition said safety stop means to permit operation of said camshaft in said reverse direction.

2. In a straight bar knitting machine having a camshaft, power means for operating said camshaft in one direction to form fabric on said machine, manual means for operating said camshaft, and a control member movable from a first position to activate said power means to operate said camshaft and to inactivate said manual means to a second position to inactivate said power means and activate said manual means to operate said camshaft, the improvement including safety stop means comprising overrunning clutch means associated with said camshaft, a first means for controlling the operation of said overrunning clutch means during operation of said camshaft in said one direction, and a second means for controlling the operation of said overrunning clutch means to control the operation of said camshaft in a direction reverse to said one direction.

3. In a machine according to claim 2 in which said first controlling means includes first arresting means for preventing rotation of said overrunning clutch means in a first direction during rotation of said camshaft in said one direction, and said second controlling means includes second arresting means for preventing rotation of said overrunning clutch means in a second direction to cause said overrunning clutch means to prevent rotation of said camshaft in said reverse direction.

4. A machine according to claim 3 in which said first arresting means includes a first ratchet and a first pawl cooperating with said first ratchet, and said second arresting means includes a second ratchet and a second pawl engageable with said second ratchet.

5. In a machine according to claim 4 in which there is means for disengaging said second pawl from said second ratchet to permit said overrunning clutch means to rotate in said second direction and permit rotation of said camshaft in said reverse direction.

6. In a machine according to claim 5 in which there is means for operating said disengaging means to disengage said second pawl from said second ratchet.

7. In a machine according to claim 5 in which there is means operated by said control member in said second position for operating said disengaging means to disengage said second pawl from said second ratchet.

References Cited UNITED STATES PATENTS 1,813,163 7/1931 Howie.

1,939,505 12/1933 Lieberknecht.

2,178,591 1l/1939 Lieberknecht.

2,363,535 11/ 1944 Lambach 66-157 X 2,649,703 8/1953 Wickardt 66-82 MERVIN STEIN, Primary Examiner US. Cl. X.R. 6682