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Be sure to read and understand this 本取扱説明書をよく読み, 内容を十分理解した instruction manual thoroughly before 上でこの製品を使用してください。 operating this product. この取扱説明書は大切に保管し, 製品の所有者 Please save this manual. When が変わった場合, この説明書も新しい所有者に ownership of this product is transferred, 手渡してください。 submit this manual to the new owner. 豊和工業株式会社 HOWA MACHINERY, LTD.
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Table of contents Introduction Safety Information Safety Precautions 1. Construction and Operation ........4 1.1 Model Coding............. 4 1.2 Construction and Operation....... 4 2. Installation ..............4 2.1 Unpacking ............4 2.2 Accessories ............5 2.3 Preparations for Installation ....... 5 2.4 Stroke Control ............
Introduction 1. This instruction manual describes the HIGH SPEED type 3-jaw draw down power chuck H3EF (standard model). 2. Please read this manual carefully and fully understand the procedures for installation, operation, inspection, and maintenance before operating the chuck. 3. Ignoring any instructions in this manual may result in a serious accident or machine damage, leading to injury to the operator or personnel near the machine.
Safety Precautions The following precautions apply to handling, maintenance, and operation of the chuck. Read and understand them carefully before use. DANGER Never operate the rotating cylinder selector valve while the spindle is rotating. Otherwise, the gripped work piece may come off and fly out. Never put any part of your body inside the spindle cover while the spindle is rotating.
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(supplied from Dow Corning Corporation) For all the chuck parts including consumables, place an order with Howa Machinery, Ltd. Howa shall not be liable for any accidents caused by use of parts not supplied from Howa. Any and all warranties are invalid unless only Howa’s genuine parts are used.
1. Construction and Operation 1.1 Model Coding The HIGH SPEED type 3-jaw draw down power chucks are sorted as follows. H3EF JIS-specified spindle nose No. No mark: : : : Having a straight socket for installation of chuck (standard model) :...
Please refer to the section 6.5 “Accessories” for particulars. 2.3 Preparations for Installation Except the direct-mount chuck of H3EF-A□ type, a chuck adapter is needed to install the chuck onto the lathe spindle. Contact us if you need information on how to design a chuck adapter.
2.5.3 Installing Chuck (1) Remove the top jaws and cover before Fig. 4 attempting to install the chuck. (2) The 8-inch chuck has a screw hole for the eyebolt on the periphery. Screw the attached eyebolt into this hole and lift the chuck.
Use extra care when operating the hydraulic or pneumatic circuit CAUTION during the chuck installation. If you actuate such circuits accidentally during chuck installation, you may be caught between the chuck body and the spindle or between the top jaw, resulting in injury. (6) Secure the chuck body to the chuck adapter using the chuck installing bolts provided as accessories.
For all the chuck parts including consumables, place an order with WARNING Howa Machinery, Ltd. Howa assumes no responsibility for accidents caused by use of the parts not prepared by Howa. Any and all warranties are void unless only Howa genuine parts are used.
3.2 Installing Top Jaws Fig. 8 (1) Select the top jaws in terms of the work piece and install them on the chuck. Before doing so, however, clean off the fitting portions of the top jaw and draw bar with a compressed air blast. What dirt or foreign matter remains can be loosened with cleaning oil, brushed vigorously, then blown off by compressed air.
3.3 Forming Top Jaws When the top jaws are installed, they must be Fig. 11 machine-formed to align flush with the work piece. The best position to clamp the work piece for this chuck is at the middle of total jaw stroke concerning the function and accuracy.
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Fig.12 1 1 1 1 ●Prepare a plug for forming the top jaws. ・In case using the standard top jaws, determine φd of a forming plug referring Fig.13 and Table6. ・φd is determined as to be that the clamping jaw stroke is the middle of full jaw stroke. ・The finish of φd part is to be around ▽▽▽.
3.4 Installing Stopper The draw down chuck cannot grip stably if the work piece is not positioned in the chuck's axial turning direction. To position the work piece here, the work piece must be pressed against the chuck's work face, but in some cases, depending on the work piece configuration, a stopper has to be equipped on the front face of the chuck.
3.5.2 Work Deformation Fig.15 When a work piece tends to be easily deformed, lowering the gripping force can minimize the deformation. However, when the rotational speed becomes too high, it is less easy to support the work piece due to the effect of the centrifugal force. Thus, great care must be taken when lowering the gripping force.
To comply with ANSl B11.6-1984 section 4.3.2, you need to install a WARNING check valve and an accumulator in the connecting area with the chuck so that the hydraulic or pneumatic system does not loose pressure in case of failure. Besides check valve and accumulator, it is essential to install a shielding cover that separates the chuck and work piece from the operator or bystanders.
Severe personal injury may result if the operator mistakenly comes WARNING into contact with a spinning chuck whose top jaws or gripped work piece have irregular contours which are not readily visible while rotating. A door or guard must be provided to prevent anyone from approaching the spinning chuck.
4. Maintenance Fig.17 4.1 Lubrication The most frequent cause of chuck failure is insufficient or improper lubrication. If lubrication is insufficient or if a non-specified lubricant is used, not only will wear be accelerated, the gripping force will be inadequate, with the possibility of the work piece coming off during the cutting operation.
4.2 Disassembly and Cleaning Even with proper lubrication, fine chips or scale can enter the chuck to jam the area of the jaw guide or wedge plunger, thus preventing smooth operation. Disassembly and cleaning must be done on a regular basis every 1000 hours. When doing so, inspect carefully for parts wear and breakage, replacing as necessary.
4.4 Setting Safe Rotational Speed ANSI B 11.6-1984 section 7.1.9 suggests guidelines for setting a safe rotational speed. A safe rotational speed will be a function of the consideration of among other things, the degree of wear and tear then existing on the jaws of the chuck, which may effect their ability to grip the work piece.
4.5 Parts List Part Name Q'ty Part Name Q'ty Chuck body Hex. socket head screw Cover Grease nipple Draw screw Bolt Draw sleeve O-ring Hex. socket head screw Back plate O-ring Round nut Guide bar Spring Set screw Steel ball Draw stud Top jaw (Soft jaw)...
5. Troubleshooting When there are any troubles with the operation of the chuck, the following causes are likely. Please check these before contacting us for service. Trouble Possible cause Recommended remedy Chuck does not operate Damaged parts on chuck. Disassemble and repair. Seizure of sliding contact part.
6. Specifications 6.1 Specifications Series number H3EF Specifications Jaw movement (Dia.) Plunger stroke (Cylinder stroke) Max. Recommended outside chucking diameter for Min. standard soft jaws (Note1) Max. Speed r/min 7000 6000 Max. input force Clamping force at Max. input force (Total jaw force) kg・m...
6.2 Dimensions Series H3EF number Symbol 90.5 100.5 M16×2 M20×2.5 Max. 47.5 Min. 35.5 14.8 19.8 Max. Min. Max. 45.3 58.3 Min. 42.7 55.7 Max. 5.70 5.70 Min. -5.70 -5.70...
6.3 Gripping Force The following graph shows the gripping force of the rotating chuck equipped with the standard soft jaws. H3EF6 H3EF8 This diagram is drawn in the condition that the jaw stroke is middle and using standard top jaws. Each diagram contains the lines indicating the claming force when the input force is lower than that of maximum.
6.5 Accessories The package box contains the accessories besides the chuck itself. Chuck size Q'ty Part name Hex. socket head bolt for mounting L=95 L=105 the chuck Hex. key spanner B=10 each B=10 B=14 Eyebolt LIMITED WARRANTY Seller warrants its products to be manufactured in accordance with published specifications and free from defects in material and/or workmanship.
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