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MODEL DH 24PM Hitachi Power Tools TECHNICAL DATA ROTARY HAMMER DH 24PM SERVICE MANUAL LIST No. E496 Sep. 2006 SPECIFICATIONS AND PARTS ARE SUBJECT TO CHANGE FOR IMPROVEMENT...
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REMARK: Throughout this TECHNICAL DATA AND SERVICE MANUAL, symbols are used in the place of company names and model names of our competitors. The symbols utilized here are as follows: Competitors Symbols Utilized Company Name Model Name GBH2-26DFR BOSCH HR2450T MAKITA...
Hitachi Rotary Hammer, Model DH 24PM 2. MARKETING OBJECTIVE The new Model DH 24PM is a 3-mode type rotary hammer based on the Model DH 24PC3 rotary hammer drill. It can provide 3 modes of operation, "Rotation and hammering," "Rotation only" and "Hammering only."...
4-1-2. Selectable from 3 modes, "Rotation and hammering", "Rotation only" and "Hammering only" The new Model DH 24PM is a 3-mode type rotary hammer based on the Model DH 24PC3 rotary hammer drill. It features the "Hammering only" mode in addition to the "Rotation and hammering" mode and the "Rotation only"...
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4-1-4. Class-top drilling speed The drilling speed of the Model DH 24PM is 1.1 times higher than B thanks to the efficient transmission of the hammering energy. 4-1-5. More comfortable and frisky drilling The Model DH 24PM can drill holes more comfortably and friskily with a light pushing force because the quantity of body jumping is 20% less than B.
5. SPECIFICATIONS 5-1. Specifications Model DH 24PM Capacity Concrete 3.4 --- 24 mm (1/8" --- 15/16") Steel 13 mm (1/2") Wood 32 mm (1-1/4") Power source AC single phase 50 Hz or 60 Hz Voltage, current and Voltage (V) power input...
5-2. Optional Accessories A. Drilling anchor holes (Rotation and hammering) Drill bit (slender shaft) (2) Adapter for slender shaft (1) Drill bit (slender shaft) (SDS-plus shank) Drill bit (slender shaft) Adapter for slender shaft Outer dia. (mm) Overall length (mm) Code No.
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B. Anchor setting (Hammering only) Anchor setting bar to permit anchor setting operation with the rotary hammer Anchor setting bar Anchor setting adapter (SDS-plus shank) Part name Code No. Part name Overall length Overall length Code No. W-1/4 Anchor setting adapter-A 302976 W-1/4 Anchor setting adapter-B 302979...
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Continuous chipping operation can cause temperature rise of the main body, resulting in failure. Bull point (round type) Square bull point Rest the Model DH 24PM about (SDS-plus shank) (SDS-plus shank) 30 minutes after continuous Code No. 303046 Code No. 316656 operation for 15 minutes.
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G. Grooving (Hammering only) Grooving chisel (SDS-plus shank) Code No. 316659 H. Driving screws (Rotation only) (2) Slotted-head (minus) bit (1) Cross-recessed head (Phillips) bit [Overall length: 50 mm] [Overall length: 70 mm] (For use with slotted-head (minus) screw) (For use with cross-recessed head (Phillips) screw) Tip thickness Stamped bit No.
6. COMPARISONS WITH SIMILAR PRODUCTS 6-1. Specification Comparisons Maker Model • HITACHI DH 24PM Item Concrete 24 mm 26 mm 24 mm Nominal capacity 13 mm 13 mm 13 mm Steel Wood 32 mm 30 mm 32 mm Power consumption...
6-2. Drilling Speed Comparison Drilling speed varies considerably depending on the work conditions. Use the factory test results shown in Fig. 1 for comparison purpose only. HITACHI DH 24PM Drilling bit diameter (mm) Fig. 1 [Test conditions] Direction : Downward drilling...
Chiseling performance varies considerably depending on the work conditions. Use the factory test results shown in Fig. 2 for comparison purposes only. Chiseling amount (kg/30 min.) Voltage Maker Model supply DH 24PM HITACHI 230 V Fig. 2 --- 11 ---...
7. PRECAUTIONS IN SALES PROMOTION In the interest of promoting the safest and most efficient use of the Model DH 24PM Rotary Hammer by all of our customers, it is very important that at the time of sale the salesperson carefully ensures that the buyer seriously recognizes the importance of the contents of the Handling Instructions, and fully understands the meaning of the precautions listed on the Caution Plate attached to each tool.
Model DH 24PM more compact for easier handling and operation. Thus, the appearance of the Model DH 24PM is similar to that of an impact drill. The rotation of the armature is transmitted to the second shaft via the first gear, and causes it to rotate. The second pinion provided on the second shaft engages the second gear mounted on the outer circumference of the cylinder.
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Accordingly, the armature shaft and the cylinder axes are also at right angles to each other. In the Model DH 24PM, through adoption of a spiral drive system (a mechanism using a reciprocating bearing), a more compact design has been achieved by arranging the armature shaft in parallel with the cylinder axis.
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Fig. 4 Slip mechanism The slip mechanism in the Model DH 24PM consists of a coil spring which applies a pre-set amount of pressure to ensure the interlocking of three claws provided on the flange of the cylinder (the final rotating shaft) and six matching claws provided on the face of the second gear, by which rotation is transmitted to the cylinder.
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Speed control The Model DH 24PM is equipped with a variable speed control switch which permits free change of the rotation speed and hammering force. When drilling in fragile materials, pull the switch trigger gently for low rotation speed (hammering force) to achieve optimum results.
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If it is hard to pull out the lock grip, put the Model DH 24PM in "Hammering only" mode then turn and pull out the lock grip. The above two steps are required to remove the lock grip for prevention of inadvertent dropping.
8-3. "Three-mode" Changeover Mechanism The change lever of the Model DH 24PM permits quick and easy changeover among the "Rotation and hammering", "Rotation only" and "Hammering only" functions. Each function mode is explained below. When operating the change lever, be sure to continue pressing the pushing button.
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(2) Rotation only (Fig. 7) Adjust the change lever to "Rotation only" ( mark). The lock plate is moved forward by the pin of the change lever, and the clutch is moved forward at the back end of the lock plate. Engagement between the clutch and the claws of the reciprocating bearing is released ( A portion in the figure).
(4) Neutral (Fig. 9) The Model DH 24PM has a neutral mode used for positioning a tool such as a flat chisel. Adjust the change lever to a position halfway between "Hammering only" ( mark) and "Rotation and hammering" ( marks).
8-5. Drill Bits The chuck section is designed exclusively for the popular and widely available SDS-plus shank bits, as shown in Fig. 10. Rotating torque is transmitted to the drill bit by two key rails provided in the tool holding section. A steel ball is used to prevent the bit from coming off.
8-7. Dust Collector (B) When drilling holes overhead, dust collector (B) can be mounted on the Model DH 24PM to prevent dust and chips from falling downward. Dust collector (B) is intended solely for use when drilling holes in concrete, and cannot be used for drilling holes in steel or wood.
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Approx. 72 mm (2-27/32") Approx. 16 mm (5/8") Grip (on the main body side) Drill bit length = 166 mm Drill bit length = 110 mm Socket adapter (B) Seal cover Socket Dust cover Retaining ring for D30 shaft Outer race Washer Steel Ball D6.35 Fig.
9. PRECAUTIONS IN DISASSEMBLY AND REASSEMBLY The [Bold] numbers in the descriptions below correspond to the item numbers in the Parts List and exploded assembly diagram. 9-1. Disassembly (1) Disassembly of the striking mechanism section Push the Second Hammer [43] in the main body with a drill bit or screwdriver to release the Striker [51] from O-ring (C) [48].
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(2) Removal of the Change Lever As shown in Fig. 16, pressing the Pushing Button [31] hard, turn the Change Lever [34] 45û counterclockwise from the "Hammering only" position ( mark). Pry out the Change Lever [34] at this position. Change Lever [34] Pushing Button [31] Fig.
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Remove the parts around the grip and the Retaining Ring for D25 Shaft [8] as shown in Fig. 19. Then Washer (B) [9], Spring [10], Lock Grip [11], Lock Ring [12], Steel Ball D7.0 [14], Washer (A) [15] and Retaining Ring for D28 Shaft [16] can be removed in this order.
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(4) Removal of the Cylinder [38] from the Gear Cover Ass'y [18] To remove the Cylinder [38] from the Gear Hand press Cover Ass'y [18], remove the Retaining Ring [17] from the Cylinder [38] first. Then support the end face of the gear cover on Cylinder [38] the gear cover jig (J-344) and press the tip of the Cylinder [38] by tapping with a hand...
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(5) Removal of the cylinder and the second gear (slip mechanism section) Remove the Retaining Ring D30 [42] from the Cylinder [38] with a retaining ring puller. Then the Second Gear [39], Spring (A) [40] and Washer (A) [41] can be removed from the Cylinder [38]. (6) Removal of the cylinder and the second hammer Remove the Stopper Ring [50] from the inside diameter portion of the Cylinder [38].
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(7) Removal of the gear cover and the pinion sleeve Pinch the Pinion Sleeve [57] with the pinion sleeve puller (J-302, No. 319265) and fix the pinion sleeve puller to a vise. Pull the Gear Cover Ass'y [18] to remove the Pinion Sleeve [57] from the Gear Cover Ass'y [18] (Figs.
Washer (D) [62] and the Lock Plate [58]. Fill Molub Alloy No. 777-1 grease in the ball portion of the Reciprocating Bearing [65]. Apply Hitachi Motor Grease No. 29 to the O-ring (S-18) [33] for the Change Lever [34] and the Steel Ball D7.0 [14].
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(3) Mounting the change lever Press the Pushing Button [31] deeply into the hole of the Change Lever [34]. Adjust the Change Lever [34] to the position shown in Fig. 26 of the Gear Cover Ass'y [18] and press it hard. Then move the Change Lever [34] to the "Hammering only"...
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(7) Mounting the bit holder or the chuck holder The bit holder or the chuck holder can be mounted by the disassembly procedure in reverse. How to mount the Lock Grip [11] is as follows. Mount the Spring [10] and the Lock Ring [12] to the Lock Grip [11] and align the Spring [10] with the notch of the Bit Holder [13].
(9) Mounting the gear cover After reassembly as shown in Fig. 31, ensure that the Change Lever [34] is adjusted to the "Hammering only" position. Engage the claws of the Clutch [61] and the Reciprocating Bearing [65] each other. Align the wing portion of the Lock Plate [58] horizontally and reinstall the Gear Cover Ass'y [18] so that the wing portion of the Lock Plate [58] is contained in the rail inside of the Gear Cover Ass'y [18].
9-4. Wiring Diagrams (1) Product with noise suppressor White Gray Black or brown Choke coil Stator Brown Cord ass'y Noise suppressor Stator Blue White or blue Black Choke coil Speed control SW Reversing SW Fig. 32 (2) Product without noise suppressor Black or brown White Gray...
9-5. Internal Wire Arrangement and Wiring Work A. Internal wire arrangement (1) Product with noise suppressor Brown (Choke coil) Black (Stator) Choke Coil (A) Blue [87] Gray (Stator) Choke Coil (A) Brown [84] White (Stator) White (Stator) Red (Stator) Blue (Choke coil) Noise Suppressor [93] Black or brown White or blue...
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(2) Product without noise suppressor Brown (CB) Black (Stator) Gray (Stator) White (Stator) White (Stator) Red (Stator) Blue (CB) Black or brown White or blue Fig. 35 --- 36 ---...
B. Additional wiring work General internal wiring can be accomplished by referring to paragraphs 9-4 and 9-5-A. The following are special instructions for switch connection. (1) Wiring of reversing switch Insert the lead wire (black) coming from the stator into the terminal (4) of the reversing switch, and the lead wire (white) into the terminal (3) as shown in Fig.
10. STANDARD REPAIR TIME (UNIT) SCHEDULES Variable 60 min. MODEL Fixed DH 24PM Work Flow Handle Cover Switch Cord Armor Cord Housing Stator Armature Ass'y O-ring (P-22) Ball Bearing (608DD) Ball Bearing (608VV) General Assembly Second Hammer Cylinder O-ring (1AP-20)
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Hitachi Power Tools LIST NO. E496 ELECTRIC TOOL PARTS LIST ROTARY HAMMER 2006 • • Model DH 24PM (E1)
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PARTS DH 24PM ITEM CODE NO. DESCRIPTION REMARKS USED 326-516 BIT HOLDER ASS’Y 1 INCLUD. 2-16 306-345 FRONT CAP 306-340 STOPPER RING 324-527 GRIP 324-528 BALL HOLDER 324-526 HOLDER PLATE 322-812 HOLDER SPRING 965-469 RETAINING RING FOR D25 SHAFT 326-520...
STANDARD ACCESSORIES DH 24PM ITEM CODE NO. DESCRIPTION REMARKS USED 324-548 SIDE HANDLE 303-709 DEPTH GAUGE 310-331 DEPTH GAUGE FOR USA, CAN 326-525 CASE OPTIONAL ACCESSORIES ITEM CODE NO. DESCRIPTION REMARKS USED 981-840 GREASE (A) FOR HAMMER. HAMMER DRILL (30G) 308-471 GREASE FOR HAMMER.
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OPTIONAL ACCESSORIES DH 24PM ITEM CODE NO. DESCRIPTION REMARKS USED 971-800 ANCHOR SETTING ADAPTER B W5/16” (MANUAL) 971-801 ANCHOR SETTING ADAPTER B W3/8” (MANUAL) 971-802 ANCHOR SETTING ADAPTER B W1/2” (MANUAL) 971-803 ANCHOR SETTING ADAPTER B W5/8” (MANUAL) 944-460 TAPER SHANK DRILL BIT D11X100 944-461 TAPER SHANK DRILL BIT D12.3X110...