Table of Contents
Advertisement
Advertisement
Table of Contents
Subscribe to Our Youtube Channel
Related Manuals for JUKI HZL-NX7
Summary of Contents for JUKI HZL-NX7
- Page 1 COMPUTER SEWING MACHINE HZL-NX7 SERVICE MANUAL...
-
Page 2: Table Of Contents
CONTENTS [1] Specifications of HZL-NX7 ...................1 [2] Search by trouble (related to mechanical components) ........3 [3] Principal parts .......................4 [4] Disassembling the machine covers ..............5 [5] PCB connection diagram ...................10 [6] Adjustment ......................14 6-1 Adjusting the needle bar height ..............14 6-2 Adjusting the needle entry point ...............15... -
Page 3: Specifications Of Hzl-Nx7
[1] Specifications of HZL-NX7 (1) Power switch • 220-240V AC common to 50/60 Hz • 120V AC common to 60 Hz (2) Power consumption • 85 W (3) Dimensions and weight • Dimensions Main unit: 575 (width) × 240 (depth) × 310 (height) (mm) •... - Page 4 (8) Pattern selection • Selection is made on the touch panel (9) Number of patterns that can be selected • Max. 70 patterns (10) Number of patterns • 351 (11) Automatic threading device • The hook section makes a turn by lowering the threading lever, and automatically returns to its original position after completion of threading. (12) Automatic lock stitch When the backtacking switch is turned ON: •...
-
Page 5: Search By Trouble (Related To Mechanical Components)
[2] Search by trouble (related to mechanical components) Phenomenon Item to be checked Faulty thread tension 6-10: Position of the hook rotation stopper plate 6-11: Adjusting the bobbin thread tension 6-12: Adjusting the needle thread tension Stitch skipping 6-1: Adjusting the needle bar height 6-2: Adjusting the needle entry point 6-5: Feed timing 6-8: Timing between the needle and the hook 6-9: Clearance between the needle and the blade point of hook Thread breakage 6-1: Adjusting the needle bar height 6-8: Timing between the needle and the hook 6-10: Position of the hook rotation stopper plate Hitch stitch 6-2: Adjusting the needle entry point Faulty material feed... -
Page 6: Principal Parts
[3] Principal parts Spool cap (large) Presser foot auto lift button Needle up/down button Spool pin Thread trimming button Bobbin winding shaft Face plate cover Threading lever LCD Screen Speed controller Presser foot lifting lever Light under arm Sensor pinhole for buttonholing Lock stitch but- Thread cutter Cloth puller top Reverse stitch feed device button Start/stop button Knee lifting lever... -
Page 7: Disassembling The Machine Covers
[4] Disassembling the machine covers ○ To remove the top cover, bow the hinge section of the right side of the cover. 1) Top cover ○ Remove setscrews 1 and 2 from the face cover. 2) Face cover Then, remove the face cover. ❶ ❷ ○ Fitting a flat-blade screwdriver (T-shape) in the nearest slot in the throat plate, 3) Throat plate push up the throat plate with the screwdriver until it comes off. Then remove the throat plate. - Page 8 ○ Remove setscrews 4 and 5 from the thread tension cover. 4) Spool cover Remove the thread tension cover. ○ Remove setscrews 6 to !0 from the spool cover. ○ R emove the bobbin winding motor junction cable from the junction connector. ○ Remove the spool cover from the main unit of the machine, paying attention to the base tension.
- Page 9 ○ Remove free-arm lower bottom cover setscrews and . Pull out the bot- 6) Bottom cover of the tom cover of the free arm in the direction of the arrow. free arm ○ Remove free-arm upper cover setscrews and . Pull out the upper cover 7) Upper cover of the of the free arm in the direction of the arrow.
- Page 10 ○ Remove setscrews to from the front panel. 9) Front panel ○ Put a thin screwdriver in the notch A in the rising section under the arm and pry off the front panel and hook B of the rear panel. (Fig 1) ○...
- Page 11 Main PCB Panel PCB SW/slide volume PCB (CN17) LED1 (CN208) Panel I/F (CN19) ○ Remove setscrews to from the rear panel. 10) Rear panel Remove the rear panel with the presser foot lifting lever raised. – 9 –...
-
Page 12: Pcb Connection Diagram
[5] PCB connection diagram • Main PCB Connec- Termi- Destination tor No. nal No. CN26 CN16 CN2 CN18 CN34 CN1 CN13 Presser-lifter 4.0Ω CN17 4.0Ω CN14 Top feed STM 4.0Ω CN31 4.0Ω CN15 Thread tension 4.0Ω CN15 4.0Ω CN13 CN19 Origin detection signal CN20 CN30... - Page 13 Connec- Termi- Connec- Termi- Destination Destination tor No. nal No. tor No. nal No. CN20 Automatic DF CN30 Knee lifter slide 3.3V 4.0Ω VR PCB Knee lifter position detec- tion signal 4.0Ω CN31 Presser foot lifting Presser foot lifting switch CN25 Main shaft de- switch cable asm.
- Page 14 • Panel PCB CN207 CN202 CN203 CN205 CN211 CN212 CN210 CN209 CN200 CN208 CN204 CN206 Connec- Terminal Connec- Destination Destination Terminal No. tor No. tor No. CN200 Panel I/F cable CN205 Reserve (Unused) (asm.) CN206 Write 3.3V 12 - 14 CN207 For external power supply S.STATE UDET...
- Page 15 • Connection block diagram Flash memory interface – 13 –...
-
Page 16: Adjustment
[6] Adjustment 6-1 Adjusting the needle bar height ○ Remove the face cover. Adjustment value: ・ Distance from the bottom end of the pin inside needle bar surface to the top surface of the throat plate: 19 mm ・ When the needle is mounted, the needle eye tilts rightward by 2 degrees. Adjustment procedure 1. 1. Select the straight stitch using the pattern selecting button. Choose center needle position. 2. Make a gauge needle by cutting a household needle HA×1 to dimension A. Fit the gauge needle into the needle bar. 3. Prepare an appropriate metal plate of thickness B. (A = 19 mm - B) 4. Bring the needle bar to its lowest dead point. Slightly loosen needle bar connecting stud setscrew ❶ as long as the needle does not slip off from the connecting stud. -
Page 17: Adjusting The Needle Entry Point
6-2 Adjusting the needle entry point ○ Remove the face cover. Adjustment procedure 1. Select the straight stitch using the pattern selecting button. Choose center needle position. 2. Assemble a needle #14 into the needle bar, loosen the setscrew in the eccentric collar and adjust the feed bar eccentric collar so that the needle meets the center of the needle slot in the throat plate when it reach- es the top surface of the throat plate by turning the hand wheel. Setscrew Feed bar eccentric collar – 15 –... -
Page 18: Feed Dog Height
6-3 Feed dog height ○ Remove the throat plate, the bottom cover of the free arm and the upper cover of the free arm. Adjustment procedure 1. Attach the throat plate after you have removed the cover. (Fig. 1) 2. Set the feed to "0" (zero). 3. Turn the handwheel to bring the feed dog to its highest point. 4. Adjust the front end of the feed dog by turning the adjustment shaft, with a thin flatblade screwdriver, from the top surface of the throat plate. (Fig. 2) To adjust the rear end of the feed dog, loosen the setscrew, and adjust the height of the feed dog, with a flatblade screwdriver or the like, by inserting the screwdriver into the adjustment hole. After the adjustment, tighten the setscrew. (Fig. 3) 5. Adjust the feed dog height both at its front and rear ends so that it juts out from the top surface of the throat plate by 1.0 ± 0.1 mm. (Fig. 4) Front end of feed dog Adjustment shaft hole Adjustment shaft Fig.1 Fig.2... -
Page 19: Timing Belt
6-4 Timing belt ○ Remove the front panel and the main PCB. Adjustment procedure 1. Loosen the setscrew in the idler mounting base and loosen the timing belt. 2. Turn the hand wheel to bring the needle bar to its lowest dead point. 3. Turn the hook driving shaft to bring the feed dog to its lowest dead point. 4. Carefully keeping the condition described in steps 2 and 3, set the timing belt on the hook driving shaft pulley (by temporarily tightening the setscrew in the idler mounting base) so that the setscrew No. 2 in the pulley is brought to just underside of the pulley. 5. Applying 0.98 ± 0.29 N force to the idler by means of a spring scale, securely tighten the setscrew. Setscrew of the idler mounting base 0.98 ± 0.29 N Setscrew No. 2 6-5 Feed timing ○ After checking the feed dog height and the needle bar height, carry out adjustment of the feed timing. Adjustment procedure 1. Assemble a HA×1 needle #14 into the needle bar. 2. Loosen setscrew No. 2 in the hook driving shaft pulley. 3. Loosen setscrew No. 1 in the hook driving shaft pulley. Adjust the pulley so that the lower end of the needle eye in the descending needle #14 is aligned with the top surface of the throat plate when the top surface of the descending feed dog is aligned with the top surface of the throat plate by turning the hand... -
Page 20: Adjusting The Shield
6-6 Adjusting the shield ○ Carry out the adjustment of the shield after you have checked the feed timing. Adjustment procedure 1. Loosen the setscrew of the shield collar. (Fig. 1) 2. Turn the hand wheel to bring the needle bar to its lowest dead point. 3. In the aforementioned state, adjust so that the marking hole in the shield is brought to the lowest position. Then, tighten the setscrew of the collar. (Fig. 2) (Caution) After tightening the setscrew, check to make sure that the shield does not come in contact with the sensor. -
Page 21: Hook Driving Shaft Coupling And The Lateral Timing Of The Hook Driving Shaft
6-7 Hook driving shaft coupling and the lateral timing of the hook driving shaft Adjustment procedure 1. Position the flat section of the hook driving shaft setscrew and the groove in the coupling so that they are in parallel with each other. (Fig. 1) (Right and left couplings (Fig. 2)) 2. When installing the hook driving cams, adjust the timing of the right and left hook driving shafts so that the timing between the right and left feed rock cams is opposite to each other. (Fig. 3) 3. At the center of the right and left hook driving shafts, tighten the coupling setscrew so that there is no backlash in the thrust direction of the coupling. (Fig. 4) (Caution) When tightening the setscrew, take care not to allow the coupling to move out of alignment from the flat section of the shaft. -
Page 22: Timing Between The Needle And The Hook
6-8 Timing between the needle and the hook ○ Remove the throat plate, the bottom cover A/B and the bottom cover of the free arm. Method for checking 1. Check to be sure that the needle entry point and needle bar height are correct. 2. Select the straight stitch. Select the right needle position by using the zigzag width adjusting dial. (The needle entry point is shifted to the rightmost side.) 3. Now, turn the hand wheel by hand to bring the needle bar to its lowest dead point. 4. Turn the hand wheel further to gradually lift the needle bar until point C where the needle center is aligned with the tip of blade point of the hook is reached. 5. At this time, check to be sure that the distance D from the tip of blade point of the hook to the upper end of the needle eye is 3.1 to 3.3 mm. If this distance is not correctly provided, carry out the following adjust- ment. Adjustment procedure 1. Loosen the setscrew in the hook driving gear which is not visible from underside of the sewing machine when the needle center aligns with the tip of blade point of the hook. 2. Select the straight stitch and the right needle position. Move the hook driving gear in the rotational direc- tion to adjust distance D of 3.1 to 3.3 mm is provided between the tip of blade point of the hook and the upper end of the needle eye when the needle bar is lifted by 1.6 mm from the lowest dead point by turning the hand wheel by hand. -
Page 23: Clearance Between The Needle And The Blade Point Of Hook
6-9 Clearance between the needle and the blade point of hook ○ Remove the face cover and the throat plate. Adjustment procedure 1. Loosen screw ❶ . Adjust the clearance between the needle and the blade point of the hook to 0.02 to 0.07 mm by turning adjusting shaft ❷ . ❷ 0.02 to 0.07 mm ❶ Adjusting the balance of the clearances at the right and left needle entry points 1. Select the zigzag pattern and set the zigzag width to 7 mm. Adjust the balance of the clearances provided between the needle and the blade point of the hook at the right and left needle entry points. Left needle position Right needle position Left needle position Right needle position... -
Page 24: Position Of The Hook Rotation Stopper Plate
6-10 Position of the hook rotation stopper plate ○ Remove the throat plate. Adjustment procedure 1. When the bobbin case holder is placed inside the rotating hook, loosen the setscrew and determine the longitudinal position of the rotation stopper plate so that the projection of the bobbin case holder and the leaf spring of the rotation stopper plate are located as illustrated in the enlarged partial view. To adjust the lateral position of the rotation stopper plate, press the plate in the right direction by the amount of play and secure with the setscrew. * The hook race surface and the bobbin case holder may be stained with dirt, oil or grease. Wipe them off with an alcohol-soaked cloth where necessary. If those parts are left stained, chattering or thread slip-off noise of the bobbin case holder can occur. Adjust so that the projection and leaf spring are aligned with this line. Setscrew Enlarged partial view 6-11 Adjusting the bobbin thread tension... -
Page 25: Adjusting The Needle Thread Tension
6-12 Adjusting the needle thread tension ○ Remove the thread tension cover. Adjustment procedure 1. Turn the power ON. Select pattern No. 001 (straight stitch). Set the thread tension to the default value (0.0). 2. Lift the presser foot. Prepare polyester thread (Schappe Spun #60) and a tension gauge. Pass the thread through the base tension, pre-tension and tension disk. 4. Lower the presser foot. Turn the adjusting nut to adjust the tension so that the tension gauge gives a read- ing of 0.49 to 0.59 N. Base tension Pre-tension Tension disk... -
Page 26: Vertical Position Of The Needle Threading Hook
6-13 Vertical position of the needle threading hook ○ Remove the face cover. Adjustment procedure 1. Assemble a household HA×1 needle #11 into the needle bar. 2. Turn the hand wheel to bring the needle bar near its highest dead point and stop the hand wheel when the needle bar reaches the location where the setscrew in the needle bar guide is visible. 3. Lower the threading lever to its lowest dead point. Check whether a clearance of 0 to 0.1 mm is provided between the top end of the needle threading hook and the upper end of the needle eye. (If the clearance is not 0 to 0.1 mm, the needle may not be threaded depending on the size of the needle used.) 4. Fit a hexagonal wrench on the needle bar guide setscrew to loosen it slightly. -
Page 27: Adjusting The Auxiliary Hook Height
6-14 Adjusting the auxiliary hook height ○ Remove the face cover. Adjustment procedure 1. Loosen the locknut. Adjust the adjusting nut so that the distance shown in the enlarged partial view is ob- tained. 2. Tighten the locknut to fix the adjusting nut. Adjusting Locknut Enlarged partial view (Caution) If the thread does not enter the guide slit of the needle threading hook when threading the nee- dle, check the distance and adjust it correctly. Guide slit –... -
Page 28: Adjusting The Opening Amount Of Auxiliary Hook
6-15 Adjusting the opening amount of auxiliary hook Adjustment procedure 1. Adjust the adjusting screw to the distance shown in the enlarged partial view. Adjusting screw 6 ± 0.2 mm Enlarged partial view Auxiliary hook (Caution) If the auxiliary hook still keeps the thread after completion of needle threading, or if the auxil- iary hook releases the thread before the needle threading hook catches the thread, adjust the adjusting screw. -
Page 29: Motor Belt
6-17 Motor belt ○ Remove the front panel. Adjustment procedure 1. Set the motor timing belt to the motor pulley and the motor shaft pulley. 2. Adjust the motor bracket so that the belt deflection amount becomes 6 ± 1 mm when pressing the center of the belt with a force of 0.98 N. After completion of adjustment, tighten the setscrew in the motor bracket. Motor pulley 6 ± 1 mm Motor bracket 0.98 N Setscrew of the motor bracket Motor shaft pulley Setscrew of the motor bracket – 27 –... -
Page 30: Longitudinal Feed
6-18 Longitudinal feed Preparation for adjustment Turn OFF the power switch. Keep pressing both the reverse stitch button and thread trimming button simul- taneously and turn ON the power switch. The service mode screen appears on the display. Select "DARN- ING" to change over the screen to the sewing pattern for adjusting darning. Adjustment procedure Carry out sewing of a darning pattern three times or more continuously in repetition. Adjust, with , so that the bottom end seam of the inner left row of a turn-back section of the darning pattern is on a line with the bottom end seam of the right row (rough indication of error: 0 ± 1 mm) third darning pattern seam is on a line, as illustrated in the figure, and confirm with Dearning... -
Page 31: Presser Foot Lifting
6-19 Presser foot lifting 6-19-1 Position of the presser foot lifting motor ○ Remove the top cover, the spool cover and the front panel. Adjustment procedure 1. Loosen the motor bracket setscrew. 2. Remove the backlash from the presser foot pressure lever gear and the presser foot lifting lever intermedi- ate gear (reduction gear). Then, tighten the setscrew. Presser foot pressure lever gear Presser foot lifting lever intermediate gear (reduction gear) -
Page 32: Adjusting The Height Of The Auto-Lifter
6-19-2 Adjusting the height of the auto-lifter ○ Remove the needle. 1. In the state the power switch is turned OFF, keep the reverse feed stitching button and the thread trimming button held pressed simultaneously until the power switch is turned ON. The Service mode screen is displayed. Proceed to the 2nd page screen and select "0mm Setting". 2. -
Page 33: Thread Trimming
6-20 Thread trimming ○ Remove the throat plate, the bottom cover of the free arm and the upper cover of the free arm. 6-20-1 Attaching/removing the thread trimmer unit How to remove the thread trimmer unit 1. Remove the micro switch setscrew. Detach the micro switch. 2. Detach the connector of the thread trimming motor. 3. Remove two setscrews of the thread trimmer unit. Detach the thread trimmer unit. Setscrews of the thread trimmer unit Thread trimmer unit Micro switch... -
Page 34: Adjusting The Thread Trimming Switch
6-20-2 Adjusting the thread trimming switch Adjustment procedure 1. Adjust so that the micro switch is turned ON when a clearance of 0.5 mm is provided between the rear end of the moving knife and the end of groove in the mechanism base. Then, tighten the setscrew. 2. Check to make sure that the aforementioned clearance becomes 0.3 mm to 1 mm or less when the thread trimmer operates and stops. At the time of adjustment After the thread trimmer has operated 0.5 mm 0.3 to 1 mm Clearance Setscrew Thread trimmer unit Micro switch – 32 –... -
Page 35: Attaching/Removing The Top Feed Dog
6-21 Attaching/removing the top feed dog How to remove the thread trimmer unit 1. Remove the cover of the top feed dog. (Fig.1) 2. Remove the slide body spring. (Fig.2) 3. Remove two setscrews. Detach the top feed dog. (Fig.3) Fig.1 Fig.2 Clinch nail Open the cover outward. Detach the clinch nail. -
Page 36: Position Of The Automatic Df Motor
6-22 Position of the automatic DF motor ○ Remove the the bottom cover A/B and the bottom cover of the free arm. Adjustment procedure 1. Turn DF cam gear ❶ in the direction of the arrow in Fig. 1 until it will go no further. 2. When DF operating part ❷ is at the position as shown in Fig. 2, turn the handwheel to check that the DF operating part is brought to the position (left side of the groove) as shown in Fig. 3. -
Page 37: Service Mode
6-23 Service mode 6-23-1 Service mode screen Check with item numbers and items. [How to select the service mode] 1. When the power switch stays off, keep pressing both the reverse feed button and the thread trimming button simultaneously to turn ON the power switch. 2. The Service mode screen is displayed. Select the item you want to check. 1st page 2nd page * Changeover the pages with shown at the upper right of the screen. - Page 38 Item name Description Operation Adjust the needle entry points on the left side of the blind stitch. Slide the needle entry points toward the needle throwing direction Blind Stitch entirely by the specified number of pulses. The adjustable range of the sliding amount is [-4 to 4]. Adjustment is made in increments of 1. Thread Trim Check Not used Sara Ukashi Bring the disks to the floating condition. (Tension release) The maximum sewing speed is 500spm(sti/min) when the straight STRAIGHT 500spm stitch pattern is selected.
- Page 40 2-11-1, TSURUMAKI, TAMA-SHI, TOKYO, 206-8551, JAPAN PHONE : (81)42-357-2341 FAX : (81)42-357-2380 http://www.juki.com Copyright C 2018 JUKI CORPORATION All rights reserved throughout the world. 40208460 2018/05...
Need help?
Do you have a question about the HZL-NX7 and is the answer not in the manual?
Questions and answers