Service Manual
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CB3-B916A CB3-B917A SERVICE MANUAL Please read this manual before making any adjustments. CHAINSTITCH BUTTON SEWER CHAINSTITCH BUTTON SEWER WITH THREAD TRIMMER
CB3-B916A CB3-B917A SERVICE MANUAL Please read this manual before making any adjustments. CHAINSTITCH BUTTON SEWER CHAINSTITCH BUTTON SEWER WITH THREAD TRIMMER
Service Manual
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... may result. Wait until the motor stops fully before using the machine. CB3-B916A/B917A When turning the machine pulley by hand, turn the pulley until the motor stops fully before starting work. • When threading the needle • When replacing the needle • When not using... needle is turned on , the machine will not be used for any maintenance and inspection of the motor's inertia. Then contact your Brother dealer or a qualified electrician to wear protective goggles and gloves when handling the lubricating oil and grease, so that they cannot move. Cleaning...
... may result. Wait until the motor stops fully before using the machine. CB3-B916A/B917A When turning the machine pulley by hand, turn the pulley until the motor stops fully before starting work. • When threading the needle • When replacing the needle • When not using... needle is turned on , the machine will not be used for any maintenance and inspection of the motor's inertia. Then contact your Brother dealer or a qualified electrician to wear protective goggles and gloves when handling the lubricating oil and grease, so that they cannot move. Cleaning...
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...26 4. Needle bar height 35 5-2. Needle bar mechanism 4 1-5. Needle guard 35 5-6. Number of stitches adjustment cam 36 5-10.Pawl of thread trimming lever 36 5-11.Button clamp driving lever 36 5-12.Worm and worm gear backlash 37 5-13.Pulley clearance in thrust direction 37 5-14...timing 38 5-18.Forward and reverse feed 38 5-19.Button clamp installation 39 5-20.Elevation amount of stitches changing 13 2-6. Troubleshooting 42 Thread trimmer mechanism 7 1-8. Number of button clamp 39 5-21.Feed timing 39 5-22.Clutch lever 39 5-23.Brake 39 5-24.Button ...
...26 4. Needle bar height 35 5-2. Needle bar mechanism 4 1-5. Needle guard 35 5-6. Number of stitches adjustment cam 36 5-10.Pawl of thread trimming lever 36 5-11.Button clamp driving lever 36 5-12.Worm and worm gear backlash 37 5-13.Pulley clearance in thrust direction 37 5-14...timing 38 5-18.Forward and reverse feed 38 5-19.Button clamp installation 39 5-20.Elevation amount of stitches changing 13 2-6. Troubleshooting 42 Thread trimmer mechanism 7 1-8. Number of button clamp 39 5-21.Feed timing 39 5-22.Clutch lever 39 5-23.Brake 39 5-24.Button ...
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1. Rotation Thread trimming lever Number of stitches adjustment lever Number of stitches 6, 8 124s Number of stitches adjustment cam Number of stitches 12, 16 125s Number of stitches 24, 32 126s Stitch 32 lever Roller Number of stitches adjustment cam Fixed knife Movable knife Cam shaft 123s 3 Thread trimming lever 1. Thread trimmer mechanism Connecting rod 4 Connecting lever Thread cutter connecting rod 2 6 5 7 Pawl Number of stitches adjustment gear 7 CB3-B916A/B917A MECHANICAL DESCRIPTIONS 1-7.
1. Rotation Thread trimming lever Number of stitches adjustment lever Number of stitches 6, 8 124s Number of stitches adjustment cam Number of stitches 12, 16 125s Number of stitches 24, 32 126s Stitch 32 lever Roller Number of stitches adjustment cam Fixed knife Movable knife Cam shaft 123s 3 Thread trimming lever 1. Thread trimmer mechanism Connecting rod 4 Connecting lever Thread cutter connecting rod 2 6 5 7 Pawl Number of stitches adjustment gear 7 CB3-B916A/B917A MECHANICAL DESCRIPTIONS 1-7.
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... Slider Rocking 132s Needle bar drive lever Slider Final stitch (B916A : non) During machine Machine stop operation 133s Machine stopped Sewing Final stitch B917A B916A Thread tension O O O -> X -> O O -> X -> X Auxiliary tension O Opens at each stitch Differs according to original position 1-9. 1.MECHANICAL DESCRIPTIONS 1-8-3. Button clamp opener [B917A] Size adjustment plate Button clamp ...claw Button clamp Button clamp plate cam opener lever 129s 130s Returns to needle bar position Main tension X X X O-Tension discs open X-Tension discs close 9 CB3-B916A/B917A
... Slider Rocking 132s Needle bar drive lever Slider Final stitch (B916A : non) During machine Machine stop operation 133s Machine stopped Sewing Final stitch B917A B916A Thread tension O O O -> X -> O O -> X -> X Auxiliary tension O Opens at each stitch Differs according to original position 1-9. 1.MECHANICAL DESCRIPTIONS 1-8-3. Button clamp opener [B917A] Size adjustment plate Button clamp ...claw Button clamp Button clamp plate cam opener lever 129s 130s Returns to needle bar position Main tension X X X O-Tension discs open X-Tension discs close 9 CB3-B916A/B917A
Service Manual
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...so that they operate correctly before using the machine. Cover 4. Needle 2-2. Brake 2. Pulley 5. Arm cover 8. Clutch tension spring 202s CB3-B916A/B917A 10 Keep the oil out of the reach of the motor's inertia. Disassembly of the sewing machine should only be carried ...out by Brother. If any safety devices have been removed, be covered by the warranty. 2-1. Needle bar cover 7. Button tray 4. Face plate thread guide 4.Sub-tension thread guide 2. V-belt 4. Set screw 10. Any problems in machine...
...so that they operate correctly before using the machine. Cover 4. Needle 2-2. Brake 2. Pulley 5. Arm cover 8. Clutch tension spring 202s CB3-B916A/B917A 10 Keep the oil out of the reach of the motor's inertia. Disassembly of the sewing machine should only be carried ...out by Brother. If any safety devices have been removed, be covered by the warranty. 2-1. Needle bar cover 7. Button tray 4. Face plate thread guide 4.Sub-tension thread guide 2. V-belt 4. Set screw 10. Any problems in machine...
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Number of stitches adjustment gear 9. Number of stitches changing 8. Snap ring 2. Snap ring 6. Thread trimming lever Thrust washer 209s Number of stitches adjustment cam 7. Set collar 1. Stitch 32 lever 5. 2. Number of stitches control lever 10. Spring 210s [B917A] 13 CB3-B916A/B917A DISASSEMBLY 2-5. Connecting rod 4. Number of stitches adjustment M gear 3.
Number of stitches adjustment gear 9. Number of stitches changing 8. Snap ring 2. Snap ring 6. Thread trimming lever Thrust washer 209s Number of stitches adjustment cam 7. Set collar 1. Stitch 32 lever 5. 2. Number of stitches control lever 10. Spring 210s [B917A] 13 CB3-B916A/B917A DISASSEMBLY 2-5. Connecting rod 4. Number of stitches adjustment M gear 3.
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up 4. Needle bar drive lever 211s 8. Tension release rod 5. Needle thread take - Needle bar 2. Drive lever shaft 212s CB3-B916A/B917A Mark 14 Needle bar clamp 1. Needle bar clamp connector 2. DISASSEMBLY 7. Spring 6. Needle bar 3. Crank rod upper part Mark 10. Set collar 11. Adjustment stud 9. 2-6.
up 4. Needle bar drive lever 211s 8. Tension release rod 5. Needle thread take - Needle bar 2. Drive lever shaft 212s CB3-B916A/B917A Mark 14 Needle bar clamp 1. Needle bar clamp connector 2. DISASSEMBLY 7. Spring 6. Needle bar 3. Crank rod upper part Mark 10. Set collar 11. Adjustment stud 9. 2-6.
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... to the needle bar drive lever . Apply grease 305s 9. Pass the adjustment shaft through the needle bar clamp , and then tighten together with the needle thread take -up lever shaft facing toward you , pass it through the tension release rod and presser driving lever , and then fit the snap ring and... -up . Fit the needle bar clamp to the needle bar clamp connector , and then fit to the tension release rod and the frame pin. 8. CB3-B916A/B917A 16 With the screw flat of the needle bar metal. * For a TQx7 needle, use the second reference line B from the bottom. With the ...
... to the needle bar drive lever . Apply grease 305s 9. Pass the adjustment shaft through the needle bar clamp , and then tighten together with the needle thread take -up lever shaft facing toward you , pass it through the tension release rod and presser driving lever , and then fit the snap ring and... -up . Fit the needle bar clamp to the needle bar clamp connector , and then fit to the tension release rod and the frame pin. 8. CB3-B916A/B917A 16 With the screw flat of the needle bar metal. * For a TQx7 needle, use the second reference line B from the bottom. With the ...
Service Manual
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Number of [Brake] (P.39). 9. Apply grease 3. Rotate the stop cam side to the clutch. 311s Contact 334s 17 CB3-B916A/B917A Fit the number of stitches adjustment M-gear , snap ring to the cam shaft . 5. Contact the stop cam (pulley) and align the marking on... . 8. ASSEMBLY AND ADJUSTMENT 3-2. Fit the clutch to the clutch shaft the set screw . * Adjust the brake while referring to the clutch shaft . 310s 6. Attach the thread trimmer lever to section Adjustment of stitches changing Mark 308s 309s 1. Turn the brake shaft until the screw is facing upward, and then secure it...
Number of [Brake] (P.39). 9. Apply grease 3. Rotate the stop cam side to the clutch. 311s Contact 334s 17 CB3-B916A/B917A Fit the number of stitches adjustment M-gear , snap ring to the cam shaft . 5. Contact the stop cam (pulley) and align the marking on... . 8. ASSEMBLY AND ADJUSTMENT 3-2. Fit the clutch to the clutch shaft the set screw . * Adjust the brake while referring to the clutch shaft . 310s 6. Attach the thread trimmer lever to section Adjustment of stitches changing Mark 308s 309s 1. Turn the brake shaft until the screw is facing upward, and then secure it...
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... loop spreader groove cam until the clearance between the loop spreader and the needle is extended farthest outward. 10. Contact lightly 19 321s CB3-B916A/B917A Place the thread handler triangular cam onto the looper setting shaft , align the reference lines, and then tighten the two screws a . Move the loop spreader groove...
... loop spreader groove cam until the clearance between the loop spreader and the needle is extended farthest outward. 10. Contact lightly 19 321s CB3-B916A/B917A Place the thread handler triangular cam onto the looper setting shaft , align the reference lines, and then tighten the two screws a . Move the loop spreader groove...
Service Manual
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ASSEMBLY AND ADJUSTMENT 4. Attach the face plate and the following parts to the frame. 8. Attach the button tray on either the left or right side of the machine bed table. 353s 27 CB3-B916A/B917A Attach the bolt to the frame. (Face plate thread guard , needle bar cover , face plate thread guide , and sub-tension thread guide ) 5. Attach the eye guard . 352s 7. Attach the needle . 6. 3.
ASSEMBLY AND ADJUSTMENT 4. Attach the face plate and the following parts to the frame. 8. Attach the button tray on either the left or right side of the machine bed table. 353s 27 CB3-B916A/B917A Attach the bolt to the frame. (Face plate thread guard , needle bar cover , face plate thread guide , and sub-tension thread guide ) 5. Attach the eye guard . 352s 7. Attach the needle . 6. 3.
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... 2. Raise the sewing machine 18. Clutch shaft 24. If any safety devices have been removed, be carried out by Brother. Steel ball 5/16 3. Thread trimming lever 408s 15. Cam shaft 19. REPLACEMENT OF PARTS 4.REPLACEMENT OF PARTS CAUTION Assembly and adjustment of the motor's... inertia. Loosen the stop screw 410s 409s CB3-B916A/B917A 28 Pulley tilt the sewing machine 8. Tilt the sewing machine ...
... 2. Raise the sewing machine 18. Clutch shaft 24. If any safety devices have been removed, be carried out by Brother. Steel ball 5/16 3. Thread trimming lever 408s 15. Cam shaft 19. REPLACEMENT OF PARTS 4.REPLACEMENT OF PARTS CAUTION Assembly and adjustment of the motor's... inertia. Loosen the stop screw 410s 409s CB3-B916A/B917A 28 Pulley tilt the sewing machine 8. Tilt the sewing machine ...
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... 3. After making the adjustment, remove the stop screw from the frame surface. 415s 29 CB3-B916A/B917A and the horizontal feed cam 414s 0 - 0.3 mm 4. The screw flat of 0 - 0.3 mm from the screw flat, insert it in the threaded part, and tighten the stop screw.) 412s 2. Feed roller < Assembly and adjustment > Screw flat...
... 3. After making the adjustment, remove the stop screw from the frame surface. 415s 29 CB3-B916A/B917A and the horizontal feed cam 414s 0 - 0.3 mm 4. The screw flat of 0 - 0.3 mm from the screw flat, insert it in the threaded part, and tighten the stop screw.) 412s 2. Feed roller < Assembly and adjustment > Screw flat...
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... button clamp driving lever . 12. Adjust the number of stitches adjustment cam to the cam shaft . 14. Attach the spring . 17. Temporarily tighten the thread trimming lever clutch shaft . Fit the connecting rod to the 15. to the connecting rod shaft , and then fit the snap ring . 419s 31... CB3-B916A/B917A REPLACEMENT OF PARTS 1 mm 1 mm 416s 417s 0.5 mm 418s 10. 4. Fit the number of stitches adjustment cam so that the clearance between ...
... button clamp driving lever . 12. Adjust the number of stitches adjustment cam to the cam shaft . 14. Attach the spring . 17. Temporarily tighten the thread trimming lever clutch shaft . Fit the connecting rod to the 15. to the connecting rod shaft , and then fit the snap ring . 419s 31... CB3-B916A/B917A REPLACEMENT OF PARTS 1 mm 1 mm 416s 417s 0.5 mm 418s 10. 4. Fit the number of stitches adjustment cam so that the clearance between ...
Service Manual
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... 0.5 - 1 mm from the stop cam are aligned. 2. The end of the button clamp driving fork and the end of the clutch. CB3-B916A/B917A 36 Number of stitches adjustment cam Screw Stopper bracket Reference line Stop cam Pulley 502s 503s Adjust the position of the stitch control... sewing machine by pressing the rear part of the driving rod claw are aligned at the final needle position. 5-10.Pawl of thread trimming lever Thread trimming lever 0.5 mm 312s Pawl Number of stitches adjustment cam The clearance between the tip of stitches adjustment cam should be 0.5 mm....
... 0.5 - 1 mm from the stop cam are aligned. 2. The end of the button clamp driving fork and the end of the clutch. CB3-B916A/B917A 36 Number of stitches adjustment cam Screw Stopper bracket Reference line Stop cam Pulley 502s 503s Adjust the position of the stitch control... sewing machine by pressing the rear part of the driving rod claw are aligned at the final needle position. 5-10.Pawl of thread trimming lever Thread trimming lever 0.5 mm 312s Pawl Number of stitches adjustment cam The clearance between the tip of stitches adjustment cam should be 0.5 mm....
Service Manual
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... needle location at the 2-hole on the paper. 4. Insert a piece of the needle bar metal, the auxiliary tension should be loosened. CB3-B916A/B917A 38 5. With the machine in the start condition, the tension discs should be 0.5 mm apart. Align the vertical feed adjustment ...the reference line of 2-hole 1. Align the vertical feed adjustment lever with the looper setting shaft. ADJUSTMENT 5-15.Auxiliary tension timing 5-16.Thread tension timing Needle bar 45 mm TQx1 Quick loosening Slow loosening Auxiliary tension 10 mm TQx7 507s 0.5 mm 508s B917A While the needle bar...
... needle location at the 2-hole on the paper. 4. Insert a piece of the needle bar metal, the auxiliary tension should be loosened. CB3-B916A/B917A 38 5. With the machine in the start condition, the tension discs should be 0.5 mm apart. Align the vertical feed adjustment ...the reference line of 2-hole 1. Align the vertical feed adjustment lever with the looper setting shaft. ADJUSTMENT 5-15.Auxiliary tension timing 5-16.Thread tension timing Needle bar 45 mm TQx1 Quick loosening Slow loosening Auxiliary tension 10 mm TQx7 507s 0.5 mm 508s B917A While the needle bar...
Service Manual
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... shoe is the stop position. 5-23.Braking force Brake shoe Set screw 516s Clutch body Brake lever shaft 1. Work clamp lift amount is too small Thread is in the direction of the horizontal feed and the vertical feed to stop before the correct stopping position, it might be caused by one... Adjust the clutch lever base so there is a 0.5 to 1 mm gap aligned with the cam positioning pin when the machine is not being trimmed 39 CB3-B916A/B917A Loosen the set the scale of the arrow. 2.
... shoe is the stop position. 5-23.Braking force Brake shoe Set screw 516s Clutch body Brake lever shaft 1. Work clamp lift amount is too small Thread is in the direction of the horizontal feed and the vertical feed to stop before the correct stopping position, it might be caused by one... Adjust the clutch lever base so there is a 0.5 to 1 mm gap aligned with the cam positioning pin when the machine is not being trimmed 39 CB3-B916A/B917A Loosen the set the scale of the arrow. 2.
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.... When the pulley is 0 - 1 mm. ADJUSTMENT 1. Synthetic thread With the machine in the stop position, set the bottom of the material, adjust the main tension for stronger tension. 519s CB3-B916A/B917A 40 5-24.Button clamp opener (B917A) Button clamp lifter lever Roller Contact... Adjustment plate Button clamp opener claw B 51702s Button clamp open lever 0 - 1 mm 5-25.Thread take-up lever Thread take-up lever Less 518s More Cotton thread Synthetic thread Adjust the thread take...
.... When the pulley is 0 - 1 mm. ADJUSTMENT 1. Synthetic thread With the machine in the stop position, set the bottom of the material, adjust the main tension for stronger tension. 519s CB3-B916A/B917A 40 5-24.Button clamp opener (B917A) Button clamp lifter lever Roller Contact... Adjustment plate Button clamp opener claw B 51702s Button clamp open lever 0 - 1 mm 5-25.Thread take-up lever Thread take-up lever Less 518s More Cotton thread Synthetic thread Adjust the thread take...
Service Manual
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... at the first stitch buttonhole, reduce the rotor setting. (Fig. If the thread end hangs out at first stitch Rotor 520s 521s 522s The standard position of the ...mark (B917A) is aligned with the take-in Increase Decrease Fig. For B916A, it is aligned with the takein. A) If the thread end hangs out at the second stitch buttonhole, increase the rotor setting. (Fig. B) 5-28.Button clamp pressure Nut (upper) Loosen...is lightly pulled. A Fig. 5. ADJUSTMENT 5-27.Rotor Take-in . Increasing the scale setting increases the thread amount. Nut 523s 41 CB3-B916A/B917A
... at the first stitch buttonhole, reduce the rotor setting. (Fig. If the thread end hangs out at first stitch Rotor 520s 521s 522s The standard position of the ...mark (B917A) is aligned with the take-in Increase Decrease Fig. For B916A, it is aligned with the takein. A) If the thread end hangs out at the second stitch buttonhole, increase the rotor setting. (Fig. B) 5-28.Button clamp pressure Nut (upper) Loosen...is lightly pulled. A Fig. 5. ADJUSTMENT 5-27.Rotor Take-in . Increasing the scale setting increases the thread amount. Nut 523s 41 CB3-B916A/B917A