HTC Desire 500, Руководство по обслуживанию

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Changing the inner belt, HTC 500/650/800
When changing the belt on the HTC 650/800, certain steps are easiest if performed
by two people.
NOTE: Never use the same screw twice.
To open the machine:
1. Disconnect the chassis from the grinding head.
2. Disconnect the motor cable (make a note of the connections).
3. Remove the cover.
4
Turn the grinding head upside-down and stand it on the motor.
5 Remove the cross from the grinding holders.
6. Remove the grinding holders.
7. Remove all the upward-facing screws, approx. 35-40 pcs.
8. Remove all the small covers, and finally the large cover (may require a crowbar).
When the machine is open, it is possible to see what is broken. Is the belt broken? Is
there a lot of dirt in the machine? Remove the upper belt. Spin the pulley to make sure it
turns freely and smoothly without making a noise. Try tipping the pulley. If it can be tipped,
the upper ball bearing is broken. If one ball bearing is broken, change all the ball bear-
ings since the cost of parts is low compared with time it takes to dismantle the machine. If
the belt has broken, this should be returned as defective to HTC. Slip marks on the belt,
however, can arise from removing carpet adhesive and due to carelessness when start-
ing up the machine (see the machine manual).
To dismantle the machine further, proceed as follows:
The machine should now look the same as in Fig. 3.
It is now time to fit the belt.
9. Remove the screw from the centre hub (requires electric or
compressed-air nut runner).
10 Use crowbars to remove the centre hub.
11. Remove the circlip from the motor plate hub (located under
the centre hub).
12. Remove the “can” from the motor and motor plate.
Use the special tool and a sledgehammer if required.
13. Put the “can” on a workbench with the open end down.
NOTE! Exercise care so that the pulley assembly does
not fall out.
14. Undo the screws securing the three shaft covers and re-
move these. Lift off the can. The pulley should remain on
the bench (may require tapping out with a non-rebounding
hammer).
16. Press the ball bearings off the shafts with an extractor or a
hydraulic press.
17. Press on new ball bearings. Make sure to press on the ball
bearing’s inner ring. 6312 ball bearings are bonded with
Loctite 603 against the shaft (for machines after 2000).
18. Position the three pulleys on the bench exactly as they were
when you removed the “can”.
19. Place the “can” over the three pulleys.
20. Apply grease to the bearings and fit the covers.
21. Secure the covers by tightening the screws in sequence.
22. Turn over the can with the pulleys now mounted and refit
the motor plate hub.
23. Fit the circlip.
24. Apply grease to the motor shaft and then fit the centre hub.
Fig. 2. Pulley
Assembly HTC 500
and HTC 650
Fig. 1. Pulley Assembly
HTC 800.
Fig. 3