Single needle direct drive lock stitcher with thread trimmer, electric feeding system and presser foot lifter (80 pages)
Summary of Contents for Brother S-7300A
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S-7300A SERVICE MANUAL Please read this manual before making any adjustments. SINGLE NEEDLE DIRECT DRIVE LOCK STITCHER WITH ELECTRONIC FEEDING SYSTEM AND THREAD TRIMMER...
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This service manual is intended for S-7300A; be sure to read the S-7300A instruction manual before this manual. Carefully read the “SAFETY INSTRUCTIONS” below and the whole of this manual to understand this product before you start maintenance. As a result of research and improvements regarding this product, some details of this manual may not be the same as those for the product you purchased.
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) indicates something that you must do. The picture inside the circle indicates the · · · · · nature of the thing that must be done. (For example, the symbol at left means “you must make the ground connection”.) S-7300A...
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Contact your Brother dealer or a qualified electrician for any electrical work that may need to Secure the table so that it will not move when tilting be done.
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If the machine develops a problem, contact your When replacing the bobbin and needle nearest Brother dealer or a qualified technician. When not using the machine and when leaving the machine unattended Do not hold the machine head by the panel when tilting it back or returning it to its original position.
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If only one hand is used, the weight of the machine Ask your Brother dealer or a qualified electrician to head may cause your hand to slip, and your hand carry out any maintenance and inspection of the may get caught.
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The following warning labels appear on the sewing machine. Please follow the instructions on the labels at all times when using the machine. If the labels have been removed or are difficult to read, please contact your nearest Brother dealer. Touching areas where high voltages are present can Be careful not to get your hands result in severe injury.
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Transformer box (100 V/400 V system only) Oil tank Control box 0874D S-7300A...
1. Clear away any tools, etc. which may be near the table holes. 2. While holding the face plate with your left hand, gently return the machine head to the upright position with your right hand. * Do not hold the operation panel. 0879D S-7300A...
・“7-12. Setting method for standard depression strokes”. ・“7-4. Adjusting the upper shaft reference position”. ・“7-5. Adjusting the feed (position, maximum pitch, vertical movement, etc.)”. ・“7-13. Adjusting the X-over seam sensor”. “3-12. Serial number checking method”. “7-14. Touch key adjustment”. S-7300A...
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3. FUNCTION SETTINGS Turn on power. S-7300A 303P If the power is turned on without any key operations 1202D S-7300A...
<Memory switch setting mode exiting method> ・ Press the return key to return to the special menu screen. <Special menu exiting method> At the special menu screen, press the home key to close the special menu ・ and switch to the home screen. S-7300A...
(*) If MSW-051 is set to "ON", thread trimming pedal operation is disabled after the presser foot lifter pedal has been operated during standing operation. OFF: No operation (only possible using presser foot lifter pedal) (*1) For other than Europe and America For Europe and America S-7300A...
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Presser foot operation when treadle is depressed forward to 1st step - (*) Displayed when MSW-852 is set to "ON" ON: Presser foot is lowered OFF: Presser foot is not lowered (*2) For other than Europe and America: ON For Europe and America: OFF S-7300A...
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Sewing motor high speed range reaching point (S4) for standing up variable speed pedal. Treadle speed curve 0~3 0: Constant Speed 1: Curves downward 2: Curves upward 3: S line curve Depression stroke (*3) For Japan: -5 For other than Japan: 0 Speed Treadleb backward Depression stroke Neutral stroke S-7300A...
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(*) When a larger value is set, the deceleration of the sewing machine motor becomes faster. When a smaller value is set, the deceleration of the sewing machine motor becomes slower. -3~6 Gain during high-speed motor operation -3~6 Gain during low-speed motor operation -3~9 Gain during thread trimming S-7300A...
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MSW-181. (*4) -3 specifications: 150~5000 (sti/min) -5 specifications: 150~4500 (sti/min) (*5) For China and Japan: 4300 (sti/min) For general export: 4000 (sti/min) -3 specifications for Europe and America: 4700 (sti/min) -5 specifications for Europe and America: 4500 (sti/min) S-7300A...
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Feed timing correction amount for auto X-over seam sewing mode -100~-1 Auto X-over seam sewing parameter A -500~3 Auto X-over seam sewing parameter B 0~1000 Auto X-over seam sewing parameter C 0~1000 Auto X-over seam sewing parameter D (*6) -3 specifications: 0 -5 specifications: -15 S-7300A...
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(sec) * The standby time is only counted at the home screen. If any other screen is displayed, the panel lock does not operate. OFF, ON Panel auto lock when turn on power - OFF: Disabled ON : Enabled S-7300A...
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* The screen will turn off during energy saving mode, but sewing is still possible. Take care to avoid operating the treadle by mistake. OFF: Energy saving mode is disabled 1- 20: Panel idle time before energy saving mode turns on (sec) S-7300A...
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Auto running ON time (seconds) (*) Only displayed when MSW-459 is set to "ON" This is only enabled when the main sewing is normal sewing or pleat presser sewing. During auto running mode, the sewing machine motor operates for the set time. S-7300A...
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This is only enabled when the main sewing is normal sewing or pleat presser sewing. ON: After the time set by MSW-460 has elapsed, the thread trimmer solenoid turns on. OFF: The thread trimmer solenoid does not operate. (*7) For Japan: OFF For other than Japan: 2 S-7300A...
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560: Delaying timing from sewing motor stops to thread wiper solenoid ON 561: Thread wiper solenoid ON time 562: Delayed timing from thread wiper solenoid is OFF to presser foot lifter solenoid is ON 10~990 Fully ON time, output signal for presser foot lifter solenoid (ms) (ms) (ms) S-7300A...
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Voltage detection constant for presser foot lifter solenoid to turn on after presser foot drop signal (*) Displayed when MSW-567 is set to "0". If it is set to "10", the response will be fastest and the operating noise will be loudest. S-7300A...
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ON: depends on MSW-057 setting OFF: Disabled ・This is not initialized during initialization mode. (*8) For China: 0 For Japan: 2 For other than the above: 1 (*9) For other than Europe and America: OFF For Europe and America: ON S-7300A...
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3: Presser foot lifter solenoid signal (Output ON when presser foot lifter solenoid is ON) 4: Automatic backtacking output signal (Output ON during automatic backtacking) 1000 300~5000 Speed selected low speed SW (option input 3) (sti/min) (*) Displayed when MSW-950 is set to "3". (sti/min) S-7300A...
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Needle counting from option input 2 is ON until option output is ON (needle) (*) Displayed when MSW-960 is set to "4". (needle) 0~99 Needle counting from option input2 is OFF until option output3 is OFF (needle) (*) Displayed when MSW-960 is set to "4". (needle) S-7300A...
Energy saving mode will then be canceled and the display will return to the previous screen. * However, if an error or a lower thread warning occurs during energy saving mode, then in such cases energy saving mode will be canceled automatically. S-7300A...
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<Memory switch setting mode exiting method> ・ Press the return key to return to the special menu screen. <Special menu exiting method > At the special menu screen, press the home key to close the special menu ・ and switch to the home screen. S-7300A...
Press the return key (5) to return to the special menu screen. <To exit from the special menu> At the special menu screen, press the home key to close the special ・ menu and switch to the home screen. S-7300A...
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Feed motor overheating sensor 0.000 ~ 3.300V temperature rises. ON when input is IN-21 Option input (IN1) ON / OFF ON when input is IN-22 Option input (IN2) ON / OFF ON when input is IN-23 Option input (IN3) ON / OFF S-7300A...
Press the return key (5) to return to the special menu screen. <To exit from the special menu> ・ At the special menu screen, press the home key to close the special menu and switch to the home screen. S-7300A...
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Upper shaft operation synchronization signal ON / OFF ON signal is output while the treadle is OUT-11 Option Output (OUT1) ON signal is output while the treadle is OUT-12 Option Output (OUT2) ON signal is output while the treadle is OUT-13 Option Output (OUT3) S-7300A...
3. Press the[ ] or [ ] key to select the desired setting. ON: Protect setting is enabled (changing settings is prohibited) OFF: Protect setting is disabled (changing settings is allowed) 4. Press the OK key to confirm the setting. S-7300A...
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2. Press the OK key to confirm the setting. <All prohibited> You can turn protection on for all functions from 1 to 15. 1. At the protect setting screen, select "All prohibited (ON)". 2. Press the OK key to confirm the setting. S-7300A...
Up to 96 error items (01 - 96) are stored in order starting from the newest. The error with history number "01" is the newest in the history. Press the return key (3) to return to the special menu screen. S-7300A...
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If you press the return key (3) without pressing the OK key (5), the error history will not be cleared. <To exit from the special menu> At the special menu screen, press the home key to close the special ・ menu and switch to the home screen. S-7300A...
Press the return key (5) to return to the special menu screen. <To exit from the special menu> At the special menu screen, press the home key to close the special ・ menu and switch to the home screen. S-7300A...
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For -[]3[] specifications, 4000 is displayed. For -[]0[] specifications, 0 is displayed. Accumulated power on time ・ Displays the accumulated power on time (x 1 sec). Accumulated motor running time ・ Displays the accumulated motor running time for the sewing machine (x 1 sec). S-7300A...
<Exiting software version checking mode> Press the return key to return to the special menu screen. ・ <Exiting the special menu> At the special menu screen, press the home key to close the special menu ・ and switch to the home screen. S-7300A...
<While version updates are running> 1. While version updating is in progress, the progress status will be displayed. * Do not turn off the power while version updating is in progress. 2. Once version updating is finished, turn off the power. S-7300A...
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<While version updates are running> 1. While version updating is in progress, the progress status will be displayed. * Do not turn off the power while version updating is in progress. 2. Once version updating is finished, turn off the power. S-7300A...
1. While pressing the menu key and the half stitch key, turn on the power to switch to the serial number checking screen. <Serial number checking mode> 1. The serial number (1) of the sewing machine will be displayed. 2. To exit, turn off the power. S-7300A...
8. Needle bar crank rod assembly 9. Needle bar clamp 10. Needle bar (1) Needle bar bush U (2) Needle bar bush D The needle bar is guided by needle bar bush U (1) and needle bar bush D (2). S-7300A...
7. Feed bar assembly 8. Feed dog Feed dog horizontal movement 1. P motor assembly 2. Feed rocker link unit 3. Feed rock shaft 4. Feed rock bracket arm 5. Feed bar shaft assembly 6. Feed bar assembly 1138D 7. Feed dog S-7300A...
(2) Upper reference line (3) Oil gauge (4) Lower reference line (5) Plunger pump * Fine adjustments can be made to the lubrication amount for the rotary hook using the adjustment screw. (Refer to “7-11. Adjusting the rotary hook lubrication amount”.) S-7300A...
The illustration below shows the mechanism with the high-speed rotary hook removed. When thread rimming signal is input 1039D 1. Solenoid plunger 2. Solenoid lever 3. Thread trimmer cam lever shaft 4. Roller (Moves to above (1)) (1) Thread trimmer cam S-7300A...
Dissemble the parts in the order shown in the illustration. * (number) indicates part names only. (It does not indicate the disassembly order.) 5-1. Knee lifter assembly 1. Bolt (Loosen) 2. Knee lifter assembly 0990D S-7300A...
(-[]0[] specifications only) Pull out Knot Hold a dish under the lubricating oil drain hole, and then remove the screw 1 to drain out the lubricating oil (1). Install the screw 1 to the lubricating oil drain hole. 1128D S-7300A...
Hold a dish under the lubricating oil drain hole, and then remove the screw 1 to drain out the lubricating oil (1). Install the screw 1 to the lubricating oil drain hole. 5-8. Stand 1. Stand L 2. Stand R [3 pcs] 1094D S-7300A...
8. Arm thread guide R 2. Pre-tension assembly S 9. Set screw 3. Set screw 10. Thread guide arm 4. Thread tension bracket assembly 11. Needle bar bush D thread guide 5. Tension release pin 6. Tension release bar S-7300A...
12. Arm thread guide R 4. Tension release bar A 13. Set screw 5. Set screw 14. Thread guide arm 6. Thread tension bracket assembly 15. Needle bar bush D thread guide 7. Thread take-up spring stopper 8. Stopper spring S-7300A...
5-15-2. Disassembling the feed bar unit 1. Screw (Loosen) 2. Lifting feed shaft unit 3. Washer 4. Vertical feed assembly 5. Screw (Loosen) 6. Feed bar shaft unit 7. Washer 8. Feed rock bracket arm 9. Feed bar assembly 1140D S-7300A...
8. Retaining ring E 9. Presser bar lifter lever spring 10. Retaining ring E 11. Washer 12. Set screw 13. Presser bar lifter lever shaft (Pull out) 14. Tension release plate 15. Washer 16. Presser bar lifter lever assembly 1097D S-7300A...
2. Presser bar lifter lever assembly (Remove in the direction of the allow) 3. Shoulder screw 4. Knee lifter lever assembly (Remove in the direction of the allow) 5. Shoulder screw 6. Knee lifter bar 5-18. Tension pulley 1104D 1. Set screws [2 pcs] 2. Tension pulleyassembly S-7300A...
1. Timing pulley U (Remove the belt from the upper shaft, and pass it over the upper shaft) 2. Timing pulley D (Remove the belt from the lower shaft) 5-23. Timing pulley U 1269D 1. Set screws [2 pcs] 2. Timing pulley U S-7300A...
Use only the proper replacement parts as specified by Brother. Use both hands to hold the machine head when tilting it back or returning it to its original position.
6. Set screw (Align with screw stop) 7. Set screw (Tighten) 8. Rotary hook shaft (Check that it rotates smoothly with no play) 9. Spacers [2pcs] 10. Set screws [2pcs] (Provisionally tighten) 11. Plunger 12. Spring 13. Cap screw pump 14. Rubber cap S-7300A...
5. Set screw (Tighten fan with set screw) 6. Set screw (Align with screw stop of gear) 7. Set screw (Tighten gear with set screw) 8. Timing pulley D 9. Spacer 4.8 10. Set screw (Align with screw stop) 11. Spacer 4.8 12. Set screw (Tighten) S-7300A...
1. Upper shaft assembly (Insert) 2. Timing pulley U(Pass the upper shaft through) 3. Set screws [2pcs] (Align the first set screw in the rotation direction with the Align the edge of timing pulley U screw stop) with the reference line. 1120D S-7300A...
1149D 1276D Upper shaft side Pass over the upper shaft and set onto the pulley. Set the needle tip and needle plate to the positions shown in the illustration. 0 ~ 1mm 1148D 1. Timing belt (1) Set screw S-7300A...
6. ASSEMBLY 6-5. Pulley and main shaft motor 1122D 1. Pulley assembly 2. Set screws [2pcs] (Align the first set screw in the rotation direction with the screw stop) 3. Bearing holder 4. Screw (Pass the tool through hole A) S-7300A...
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3. Tighten the two set screws (6) to secure the machine motor shaft. First tighten the set screw (6) on the screw stop side. The reference line (7) is the mark on the screw stop. Screw stop side 1204D S-7300A...
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6. ASSEMBLY 4. Connect the 16-pin sewing machine motor encoder connector (8) and the 4-pin sewing machine motor connector (9), and then install the harness clamp (10). 1205D S-7300A...
Pass the knee lifter bar 1 through the hole near the front of the bed. 1154D 1. Knee lifter bar 2. Shoulder screw 3. Knee lifter lever assembly 4. Shoulder screw 5. Presser bar lifter lever assembly 6. Shoulder screw S-7300A...
4. Set screw (Align with screw stop) 11. Set screws [2 pcs] (Align with screw stop) 5. Set screws [2 pcs] (Tighten) 12. Rubber cap 13. Rubber cap 6. Needle bar bush U 14. Rubber cap 7. Needle bar guide slide block S-7300A...
12. Screw (Provisionally tighten) 3. Washer 4. Tension release plate 13. Washer 14. Presser bar spring 5. Washer 15. Spring guide 6. Retaining ring E 16. Presser adjusting screw 7. Presser bar lifter lever spring 8. Retaining ring E 9. Set screw S-7300A...
1161D 1. Feed bar unit (Place onto lower shaft (1)) 2. Washer 3. Feed rock shaft 4. Feed rocker link unit 5. Set screws [2 pcs] 6. Washer (1) Lower shaft (2) Feed shaft bush R S-7300A...
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1165D Check that the PM arm 8 moves smoothly. 7. Feed motor (Place onto PM arm 8.) 8. PM arm 9. Motor bracket 10. Socket bolts [4 pcs] 11. Set screws [2 pcs] (1) Motor shaft S-7300A...
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12. Screw (Align with the reference line on the lower shaft (1) and provisionally tighten) 13. Set screws [2 pcs] (Provisionally tighten) 14. Screw (After adjusting the feed dog position, fully tighten) 15. Set screws [2 pcs] (Align with the reference line on the lower shaft (1) and fully tighten) (1) Lower shaft S-7300A...
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4) Adjust the feed rocker bracket arm so that the clearance between the front of the feed dog and the needle plate is 0.5 mm for -[][] specifications, 3 mm for -[][]5 specifications, and 0.1 mm at the left side. 5) Tighten the screw (c) of the feed rocker bracket arm. S-7300A...
15 ml of lubricating oil is added to the gearbox at the time of shipment from the factory. If oil overflows from (a) in the situation shown in the illustration at left, add lubricating oil via hole (b). 1174D S-7300A...
4 so that the distance between the presser bar bracket (c) and the top of the X-over seam sensor 3 is 21.5 mm while the presser foot (a) and the 1004D needle plate (b) are touching. 3. X-over seam sensor assembly 4. Screws [3 pcs] S-7300A...
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Install so that the arm and the face plate are correctly aligned. 5. Face plate 6. Screws [4 pcs] 1005D 1006D Place the cushion (a) of the hand switch 1 against the arm (b), and then fully tighten the screw 7. 7. Screws [2pcs] (Fully tighten) S-7300A...
1113D Bind the panel and main shaft motor harnesses Bind the harnesses of the feed motor and the thread together also. trimmer solenoid together. 1. Cord holder 2. Screw 3. Cord holder 4. Screw 5. Cord holder 6. Screw S-7300A...
1. Needle bar bush D thread guide 8. Thread tension bracket assembly 2. Thread guide arm 9. Set screw 3. Set screw 10. Pre-tension assembly S 4. Arm thread guide R 11. Set screw 5. Screw 6. Tension release bar S-7300A...
3. Set screw 12. Tension release bar A 4. Arm thread guide R 13. Tension release pin A 5. Screw 14. Pre-tension assembly P 6. Tension release bar assembly 15. Set screw 7. Tension release pin 8. Stopper spring S-7300A...
8. Screws [2 pcs] (Tighten) 4. Screws [2 pcs] (Tighten) 9. Set screw collar 10. Set screws [2 pcs] (Tighten) 5. Washer <Adjustment> 1) Adjust the direction of the thread wiper crank unit 1. Set so it is straight. 1175D S-7300A...
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Place the thread wiper lever (1) against the lever stopper assembly 3. 1177D 4) Adjust the position of the thread wiper. If adjustment is not possible with just the thread wiper, adjust the direction of the thread wiper crank unit 1. Aligned with presser foot 1178D S-7300A...
If only one hand is used, the weight of the machine Ask your Brother dealer or a qualified electrician to head may cause your hand to slip, and your hand carry out any maintenance and inspection of the may get caught.
Do not adjust the tension of the thread take-up spring if the presser foot has been raised by the lifting lever, or if the thread trimmer solenoid is ON. <-[ ][ ]3> <-[ ][ ]5> 0.25 - 0.35N 0.3 - 0.5N 0913D S-7300A...
(1) is at the standard height of 6 mm. Tighten the bolt (6). Install the rubber cap (5). Adjust the presser foot pressure using the presser adjusting screw (4), and then tighten the nut (3). 0915D S-7300A...
It is recommended that you use the Unitta U-508 tension gauge. [Measurement position] Microphone position Pressing position View [D] 0988D 3. Tighten the two set screws (10) of the tension pulley (9). First tighten the set screw (10) at [A] shown in the illustration. 0968D S-7300A...
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4. Install the pulley cover (1). 0960D While pressing the menu key (16), press the power 0969D switch (17). 6. Select "Input checking" (18) from the special menu. (16) 7. Touch the key (19) to select "Upper shaft rotation angle" (20). (18) (19) (20) S-7300A...
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Do not touch the machine pulley (12). 0986D 13. While touching the menu key (16) and the home key (25), 0969D press the power switch (17). 14. Select "U-shaft REF position ADJ" (26). 15. Press the OK key (27). (16) (25) (26) (27) S-7300A...
1089D 2. While pressing the menu key (3) and the home key (4), 1090D press the power switch (5). 3. Select "Feed REF position ADJ" (6). 4. Place a scale (7) or similar against the feed dog (8). 1091D S-7300A...
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12. If they touch, re-adjust the position of the feed rocker bracket arm, or reduce the setting for memory switch 200 by following the method in "Matching the stitch length" in the next section. Set to maximum pitch All OFF S-7300A...
The stitch length for reverse stitches during start backtacking can be adjusted separately using memory switch No. 202, and the stitch length for reverse stitches during end backtacking can be adjusted separately using memory switch No. 203. S-7300A...
(Fig. (B)) (Refer to "7-5-4-2. Adjusting the feed dog angle" lower on the nextpage for details of this operation.) 0916D Becomes Becomes Becomes higher higher higher Needle plate Standard Standard Standard Becomes Becomes Becomes lower lower lower 0930D 0931D S-7300A...
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The height of the feed dog (2) will change after the angle has been adjusted, so it will be necessary to re-adjust the height of the feed dog (2). Back is lowered Front is raised Standard Standard Back is raised Front is lowered 0933D S-7300A...
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NOTE: If the feed lifting eccentric cam (4) is turned too far in the direction of <A>, it may cause the needle to break. After adjusting, securely tighten the set screw (5). Press the home key (6). Needle timing is (Standard) Needle timing is retarded advanced 0920D S-7300A...
5. After adjusting, turn on the power and turn the pulley by hand to operate the sewing machine, and check that none of the drive parts touch any other parts. Reference line Vertical feed amount becomes larger -[][]3 -[][]5 standard standard position position Vertical feed amount becomes smaller 1084D S-7300A...
If the value is increased, the feed timing will be advanced relative to the needle, and if the value is decreased, the feed timing will be delayed. You can change the feed timing for special loci in the same way using memory switch Nos. 251 to 253. S-7300A...
(9) up or down to adjust so that the height of the feed dog (3) changes from the 1.5mm standard value of 1.2 mm to 1.5 mm. 6. Tighten the set screw (6) of the vertical feed assembly (5). Becomes higher Becomes lower 1183D S-7300A...
Remove the rubber cap (3) from the face plate. Loosen the screw (4) and move the thread wiper (1) up or down to adjust its position. Securely tighten the screw (4). Install the rubber cap (3). 0918D S-7300A...
(7) is enough to allow the thread being used to pass through smoothly. The clearance should be 0.4 to 0.7 mm (for -[][]3 specifications) and 0.6 to 1.1 mm (for -[][]5 specifications). <-[][]3> 0.4 - 0.7mm <-[][]5> 0.6 - 1.1mm 0921D 2293M S-7300A...
(1) until it touches the screw stop on the thread take-up support shaft (3). 5. After this, tighten the set screw (2). 6. Install the face plate. Screw stop 0906D S-7300A...
To raise the presser foot (1)…Turn the adjusting screw ・ (6) clockwise. To lower the presser foot (1)... Turn the adjusting ・ screw (6) counterclockwise. Tighten the nut (7). After making the adjustment, sew a piece of material to check the floating amount. Raise Lower 0922D S-7300A...
2. Loosen the nut (1). 3. Adjust the position of the backup pin (3) so that the clearance between the tension release plate (2) and the backup pin (3) is 0.1 to 0.2 mm. 4. Tighten the nut (1). 0.1 - 0.2mm 1013D S-7300A...
3. Move the tension stud bracket assembly (6) forward or back to adjust so that the thread take-up spring stopper (8) does not protrude from the surface [A] shown in the illustration (indent 0.6 mm or less). 4. Securely tighten the set screw (3). 1274D S-7300A...
(6) of the tension stud bracket assembly (5) are at the position where they are just starting to open when the clearance between the thread trimmer solenoid (3) and the plunger (4) is 4 mm. 1017D Starting to open 1018D S-7300A...
(4) so that the clearance between the tension release plate (3) and the backup pin (4) is 0.1 to 0.2 mm. 3. Tighten the nut (1). Touching 0.1 - 0.2mm 1019D S-7300A...
(7) so that the clearance between the tension release plate (5) and tension release bar A (6) is 0.05 to 0.1 mm. 4. Tighten the set screw (3). 11mm 1020D Thread trimmer solenoid ON position Touching 0.05 - 0.1mm 1021D S-7300A...
(non-cam part) of the tension release plate (4). (Premier specifications only) 3. The opening amount for the main tension discs (5) should be 0.6 mm or more. Cam part Flat part 0.6mm or more 1025D S-7300A...
"Checking the lubrication amount" above. Check the lubrication amount again after the sewing 0911D machine has been used for approximately two hours Check the lubrication amount again after the sewing machine has been used for approximately two hours. S-7300A...
(With the treadle depressed to the maximum backward position, touch the OK button on the LCD panel.) display will show that the setting is completed. 1064D The display will automatically Turn off the power switch to exit from the adjustment return to the adjustment menu. menu. S-7300A...
4. Lower the presser foot (6), and then press the OK key (7). 5. Insert the 4 mm spacer (9) in between the presser foot (6) and the needle plate (8), and then press the OK key (7). 6. Turn off the power switch(3). 1050D 1051D S-7300A...
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OK key (3), it is possible that the sensor is in the incorrect position. Reassemble so that the distance between the top of the presser bar clamp (4) and the top of the X-over seam sensor (5) is 21.5 mm when the presser foot is lowered. 21.5mm 1052D S-7300A...
If the coordinates which are read are within the allowable range, the coordinate checking screen is displayed. On the other hand, if the coordinates which are read are outside the allowable range, the buzzer will sound twice, so repeat the operation. S-7300A...
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To confirm the adjustment values and exit, press the half stitch key. On the other hand, if you would like to repeat the procedure from the beginning, press the menu key. * The procedure returns to step 2. Once the adjustment values have been saved, turn off the power. S-7300A...
Use only the proper replacement parts as specified head may cause your hand to slip, and your hand by Brother. may get caught. Turn off the power switch and disconnect the power Be sure to wear protective goggles and gloves when cord before replacing any parts.
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* Tighten the screw (8) so that there is no play in the forked shaft (9). * The lower thread finger (10) must be underneath the movable knife (6). 3. Install the feed dog, needle plate and presser foot. 4352M 1mm - 1.5mm 1mm - 1.5mm 1189D 1190D S-7300A...
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(4) do not touch when the roller shaft (4) returns to the right. (Fig. [B]) * Tighten the two set screws (5) to approximately 4 N.m. Direction of cam rotation 0.5mm - 1.0mm Should not touch 1196D S-7300A...
(11) is slightly visible. (The head of the screw (9) is pan-shaped, and so the upper knife (10) can pivot on this screw when it is tilted.) 0952D S-7300A...
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(12) moves the thread trimmer cam roller (13) to its maximum displacement position. Make sure that the thread trimmer solenoid does not turn off and does not return during this step. 0955D S-7300A...
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11. Tighten the screw (2) of the thread trimmer lever (1). Make sure that there is no play in the thrust direction in the forked shaft (15) of the thread trimmer lever (1) (see illustration on page 9). 0957D S-7300A...
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3. Check that the edge of the thread trimmer cam (2) and the roller shaft (4) do not touch when the roller shaft (4) returns to the right. (Fig. [B]) * Tighten the two set screws (5) to approximately 4 N.m. Should not touch 0.5mm 1.0mm 1196D S-7300A...
8-3. Main shaft motor 1. Tilt back the machine head. 2. Remove the pulley cover (1). 0960D 3. Remove the harness clamp (2). 4. Disconnect the 16-pin sewing machine motor encoder connector (3) and the 4-pin sewing machine motor connector (4). 0961D S-7300A...
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(8). 0963D 7. Momentarily return the machine head to its original position, and then loosen the two set screws (10) of the tension pulley (9). 8. Turn the tension pulley (9) to loosen the belt tension. 0964D S-7300A...
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11. Tighten the two set screws (6) to secure the machine motor shaft. First tighten the set screw (6) on the screw stop side. The reference line (13) is the mark on the screw stop. Screw stop side 0966D S-7300A...
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8. REPLACING PARTS 12. Connect the 16-pin sewing machine motor encoder connector (3) and the 4-pin sewing machine motor connector (4), and then install the harness clamp (2). 0967D S-7300A...
8-4. Feed motor 1. Tilt back the machine head. 2. Remove the pulley cover (1). 0960D 3. Remove the three harness clamps (2). 4. Disconnect the 6-pin feed motor encoder connector (3) and the 6-pin feed motor connector (4). 0972D S-7300A...
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(6). 0973D 6. Remove the tubes (8) from the three tube bands (7). 7. Remove the screw (10) of the motor cover (9). 0974D 8. Loosen the two set screws (12) of the PM arm (11). 0975D S-7300A...
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0977D 11. Place the motor bracket (13) against the top-right of the processed surface of the bed, and then secure it by tightening the four socket bolts (14). Check that the PM arm (11) moves smoothly. 0978D S-7300A...
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15. Install the tension release wire (6) with the nut (4) and wire holder D (5). 16. Connect the 6-pin feed motor connector (4) and the 6-pin feed motor encoder connector (3). 17. Install the three harness clamps (2) 18. Install the pulley cover (1). 0979D S-7300A...
8-5. Feed bar shaft, lifting feed shaft When changing over these parts, apply grease as described below and then install the parts to the sewing machine. * Use Brother-specified grease (SA8837-001). 1. Apply grease to the holes of each part as shown in the...
8. REPLACING PARTS 8-6. Panel 8-6-1. Replacing panel 1029D 1. Tilt back the machine head. 2. Remove the pulley cover (1). 3. Return the machine head to its original position. 4. Remove the top cover (2). 1030D S-7300A...
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5. Remove the cord holder (3) and the harness clamp (4). 6. Disconnect the 10-pin operation panel connector (5). 1033D 7. Loosen the two set screws (6). 8. Remove the cap (7) and the screw (8). 9. Remove the panel (9). S-7300A...
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12. Fit the panel (9) to the machine head, secure it with the two set screws (6) and the screw (8), and then install the cap (7). 1034D 1053D 13. Install the cord holder (3) and the harness clamp (4). Tighten the ground wire (12) together with the cord holder (3) at this time. 14. Connect the 10-pin operation panel connector (5). S-7300A...
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8. REPLACING PARTS 1029D 15. Install the top cover (1). 16. Install the pulley cover (2). 1030D S-7300A...
8-6-2. Adjusting the tension stud bracket assembly position 1. Adjust so that the thread path hole (2) in the bobbin winder tension assembly (1) is in the position relative to the bobbin case (3) shown in the illustration. 1038D S-7300A...
6. Use a cloth to wipe away any excess grease from around the rubber caps and set screws and from underneath needle bar bush D. 7. Clear the setting while referring to "Clearing the grease 1103D consumption amount". S-7300A...
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9. APPLYING GREASE <Resetting the grease consumption amount> 1093D 1. While pressing the menu key (1), press the power switch (2). 2. At the special menu, select "Grease up" (3). 3. Press the OK key (4). S-7300A...
In such a case, be careful not to touch any place other than that for the measurement. In addition, always keep in mind that a high voltage remains for about 5 minutes after power is turned off. Injury When separating or rejoining connectors, and measuring something, be careful not to cut your fingers on metal parts such as heat sinks and covers. S-7300A...
Most of the machine trouble is due to connector problems including improper connection or sufficient contact. Therefore, be sure to check if each connector is correctly inserted and that there is no contact failure between pins and wires before starting troubleshooting procedures. 10-2-1. Connector positions Main PCB 1069D 1070D S-7300A...
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Slow speed switch Needle down signal output (*1) Presser foot switch Needle up signal output (*1) Variable speed input Sewing machine motor encoder (*1) Start/stop signal output (*1) Option Output 1 (*1) Option Output 2 (*1) (*1) Open collector (*2) MSW960 S-7300A...
If a component on a PCB is damaged, the fuses may blow again soon even after they have been replaced. Part name Part code When a fuse has blown Fuse 50T100H The power indicator is not illuminated, and nothing SB2725-001 (glass tube fuse,10A250V) operates. Main PCB Power indicator (Red LED) 1071D S-7300A...
2. Measure the resistance of the feed motor connector (2) using an ohmmeter in the x 1 range. If the value is as shown in the table below, the connector is normal. Between 2 - 3 Approx.2.6Ω Between 5 - 6 1073D S-7300A...
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AC voltage range of a multimeter, and check that the voltage is within the allowable range for the specified voltage rating. If the value is as shown in the table below, the connector is normal. Between 2 - 3 AC 180V - 265V Ground wire 1074D S-7300A...
Presser foot lifter switch (*2) (*1) Depends on which solenoid is installed (*2) 0 Ω when switch is ON, ∞ Ω when switch is OFF For options Thread trimmer solenoid Presser foot lifting solenoid Thread wiper solenoid Presser foot lifter switch 1075D S-7300A...
Adjust the tension of the thread take-up spring. 114* ・ Is the needle and rotary hook timing correct? Adjust the height of the needle bar. 128* Adjust the clearance between the needle and the tip of the rotary hook. 129* S-7300A...
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・ Is the presser foot being raised before the sewing machine has stopped sewing? Raise the presser foot after the sewing machine has stopped sewing. Large bird's nests ・ Is the upper thread trailing length too long after thread trimming? forming sewing Increase the tension of the pre-tension. 135・136 start. S-7300A...
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・ Is the bobbin turning smoothly? 0751M If the bobbin is not turning smoothly, replace the bobbin. ・ Is a bobbin other that the light-alloy bobbins specified by Brother being used? Instruction Use only bobbins which are specified by Brother.
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3. Keep pressing the best PFM mode key, and then select "T/T Instruction short parameter". manual (1) Delete the stitch pitch for the previous stitch. (2) Decrease the sewing speed for the final stitch and the stitch before it. Stitch pitch for 1st stitch Stitch pitch for 2nd stitch S-7300A...
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・ Adjust so that the tips of the movable knife and fixed knife are 145* meshing. (Other than premier specifications) ・ Adjust the tip of the upper knife to the lower knife index position so 149* that the knives mesh.(Premier specifications) S-7300A...
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Is the knee lifter being used before the sewing machine has stopped? ・ Adjust the tension release switching plate upward to retard the tension release timing. Thread take-up spring Adjust the tension release switching plate upward to retard the ・ stopper thread tension release timing. take-up spring are twisted together. S-7300A...
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Instruction Insert connectors manual securely. 0925D "Grease up" flashes in the ・ This display is to notify you that it is time to apply grease. panel display when the Apply grease. 165* power switch is turned on. S-7300A...
・ For items with "**" appearing in the "Page" column, ask the place of purchase for advice. <Connector layout diagram> Connector P2 Connector P4 Connector P1 Connector P3 Connector P5 Sewing machine motor connector Power supply connector Feed motor connector 0926D Main P.C. board Connector P13 Connector P6 0927D S-7300A...
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Turn off the power and check the sewing conditions. motor. E151 Motor overheating sensor connection was not Turn off the power and check the connection of detected. connector P5. E161 Sewing machine motor overload was detected Turn off the power and check the sewing conditions. during sewing. S-7300A...
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Model settings could not be read from machine Turn the power off and then back on again. head memory (internal panel). E451 Data backup cannot be written to machine head Turn the power off and then back on again. memory (internal panel). S-7300A...
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Error occurred during version update. Turn off the power, and then repeat the version update procedure. If an error code that is not listed above appears or if carrying out the specified remedy does not solve the problem, contact the place of purchase. S-7300A...