There are a lot of questions about HSM today and many different, more or less complicated, definitions can be seen frequently. Here the matter will be discussed in an easy fashion and from a practical point of view. This article is the first in a series of articles about die and moldmaking from Sandvik Coromant. In a following article HSM will be further discussed.
Historical background The term High Speed Machining (HSM) commonly refers to end milling at high rotational speeds and high surface feeds.
This paper describes a new hardware algorithm for morpheme extraction and its implementation on a specific machine (MEX-I), as the first step toward achieving natural language parsing accelerators. It also shows the machine's performance, 100-1,000 times faster than a personal computer. This machine can extract morphemes from 10,000 character Japanese text by searching an 80,000 morpheme dictionary in I second. It can treat multiple text streams, which are composed of character candidates, as well as one text stream.
Keywords: Screw Drive, Dynamic Model, Vibration Modes, Ritz Series.
Abstract. The ball screw drives are among the most commonly mechanisms used to provide motion in high speed machine tools. The most important factor that affects high speed positioning accuracy is the closed loop bandwidth, which in turn is affected by the structural vibration modes.
C H A P T E R
A Textbook of Machine Design
Engineering Materials and their Properties
1. Introduction. 2. Classification of Engineering Materials. 3. Selection of Materials for Engineering Purposes. 4. Physical Proper ties of Metals. 5. Mechanical Properties of Metals. 6. Ferrous Metals. 7. Cast Iron. 9. Alloy Cast Iron. 10. Effect of Impurities on Cast Iron. 11. Wrought Iron. 12. Steel. 15. Effect of Impurities on Steel. 16. Free Cutting Steels. 17. Alloy Steels. 19. Stainless Steel. 20. Heat Resisting Steels. 21.
Flat belts drives can be used for large amount of power transmission and there is no upper limit of distance between the two pulleys. Belt conveyer system is one such example. These drives are efficient at high speeds and they offer quite running. A typical flat belt drive with idler pulley is shown in Fig. 13.2.1. Idler pulleys are used to guide a flat belt in various manners, but do not contribute to power transmission. A view of the flat belt cross section is also shown in the figure.
SUMMARY This chapter addresses the design of cam systems in which flexibility is not a consideration. Flexible, high-speed cam systems are too involved for handbook presentation. Therefore only two generic families of motion, trigonometric and polynomial, are discussed. This covers most of the practical problems. The rules concerning the reciprocating motion of a follower can be adapted to angular motion as well as to three-dimensional cams. Some material concerns circular-arc cams, which are still used in some fine mechanisms....
The machining of complex sculptured surfaces is an important technological topic
in modern manufacturing, namely in the molds and dies sector. Today, this sector,
with great importance to automotive, aircraft and others advanced industries, is
placed in all industrialized or emerging countries. In the recent past, the traditional
technology employed in molds and dies manufacture was a combination of con-
ventional milling and electro-discharge machining (EDM) or electrochemical
Andrzej A. Ol?dzki, D.Sc.f Warsaw Technical University, Poland
SUMMARY / 40.1 40.1 CAM MECHANISM TYPES, CHARACTERISTICS, AND MOTIONS / 40.1 40.2 BASIC CAM MOTIONS / 40.6 40.3 LAYOUT AND DESIGN; MANUFACTURING CONSIDERATIONS / 40.17 40.4 FORCE AND TORQUE ANALYSIS / 40.22 40.5 CONTACT STRESS AND WEAR: PROGRAMMING / 40.25 REFERENCES / 40.28
SUMMARY This chapter addresses the design of cam systems in which flexibility is not a consideration. Flexible, high-speed cam systems are too involved for handbook presentation.
The years 1945–55 saw the emergence of a radically new kind of device: the high-speed
stored-program digital computer. Secret wartime projects in areas such as code-breaking, radar and ballistics had produced a wealth of ideas and technologies that
kick-started this first decade of the Information Age. The brilliant mathematician and
code-breaker Alan Turing was just one of several British pioneers whose prototype
machines led the way.
Turning theory into practice proved tricky, but by 1948 five UK research groups
had begun to build practical stored-program computers.
Volume II of the Handbook of Lubrication (Tribology) provides coverage of basic theory involved in friction, wear, and lubrication; characteristics and application practices for lubricants; and design principles for lubricated machine elements such as bearings, gears, couplings, and seals.
Variable voltage, variable frequency operation of induction machines is realised utilising autonomous
inverters, in conjunction with a rectifier and a DC link circuit. The voltage source inverter (VSI) is the
most frequently applied power supply source for speed control of induction motors. It can be operated in
six-step mode or in PWM mode. Six-step operation will be considered first.
As far as the AC machines are concerned, simple speed control systems are not capable of providing
decoupled (independent) flux and torque control. All the so called scalar speed control methods
(constant volts/hertz control, slip frequency control, voltage control etc.) are able of controlling the
steady-state behaviour of the machine only.
The term magnetic bearing refers to devices that provide stable suspension of a rotor. Because
of the contact-less motion of the rotor, magnetic bearings offer many advantages for various
applications. Commercial applications include compressors, centrifuges, high-speed turbines,
energy-storage flywheels, high-precision machine tools, etc.
Magnetic bearings are a typical mechatronic product. Thus, a great deal of knowledge is
necessary for its design, construction and operation.