Machine Component Design EMD223 Machine Component Design Dr. Mohamad Yusof Idroas Email: meyusof@eng.usm.my Room: 3.10 (SoME)

31/5: Final report submission EMD223 Important Dates Test #2 24 May 2012 (Thu) 2pm – 4pm Project #2 30/5-31/5: Presentation 31/5: Final report submission

To be uploaded in eLearning EMD223 Assignment #2 To be uploaded in eLearning by15 May 2012 (Tue) Due Date: 21 May 2012 (Mon)

Clutches, Brakes & Flywheels

Introduction BAND BRAKES The SIMPLEST braking devices A band brake is a primary or secondary brake, consisting of a band of friction material that tightens concentrically around a cylindrical piece of equipment to either prevent it from rotating (a static or "holding“ brake), or to slow it (a dynamic brake). The band is usually made of steel and lined with a woven friction material for flexibility. What is jiggering process? Jiggering is a motion in which the clay bat is formed by means of templates or rollers. The jiggering process is limited to axisymmetric parts and has limited dimensional accuracy. Automation of this process is necessary to improve productivity. The layered structure of clay can be formed with anisotropic behavior of the material both in subsequent processing and in the final properties of the ceramic products What is anisotropy? What is anisotropic behavior? Figure 1: Band Brake

Introduction ADVANTAGES OF BAND BRAKES: Band brakes can be simple, compact, rugged, and can generate high force with a light input force. DISADVANTAGES OF BAND BRAKES: Band brakes are prone to grabbing or chatter and loss of brake force when hot. APPLICATIONS: Chain saws, bicycle brakes, winch drums Locking of gear rings in epicyclic gearing What is jiggering process? Jiggering is a motion in which the clay bat is formed by means of templates or rollers. The jiggering process is limited to axisymmetric parts and has limited dimensional accuracy. Automation of this process is necessary to improve productivity. The layered structure of clay can be formed with anisotropic behavior of the material both in subsequent processing and in the final properties of the ceramic products What is anisotropy? What is anisotropic behavior?

Epicyclic (Planetary) Introduction APPLICATIONS: What is jiggering process? Jiggering is a motion in which the clay bat is formed by means of templates or rollers. The jiggering process is limited to axisymmetric parts and has limited dimensional accuracy. Automation of this process is necessary to improve productivity. The layered structure of clay can be formed with anisotropic behavior of the material both in subsequent processing and in the final properties of the ceramic products What is anisotropy? What is anisotropic behavior? Epicyclic (Planetary) Gear Train Winch Drum

Design Analysis Based on Figure 1, friction forces acting on the band serve to increase P1 and decrease P2. Consider drum and band portion as a free body above the cutting plane, brake torque (T) is determined as: What is jiggering process? Jiggering is a motion in which the clay bat is formed by means of templates or rollers. The jiggering process is limited to axisymmetric parts and has limited dimensional accuracy. Automation of this process is necessary to improve productivity. The layered structure of clay can be formed with anisotropic behavior of the material both in subsequent processing and in the final properties of the ceramic products What is anisotropy? What is anisotropic behavior? Figure 1: Band Brake

Design Analysis The applied lever force (F): Forces acting on an element of the band for small angle dϴ (based on Figure 2): What is jiggering process? Jiggering is a motion in which the clay bat is formed by means of templates or rollers. The jiggering process is limited to axisymmetric parts and has limited dimensional accuracy. Automation of this process is necessary to improve productivity. The layered structure of clay can be formed with anisotropic behavior of the material both in subsequent processing and in the final properties of the ceramic products What is anisotropy? What is anisotropic behavior? Figure 2: Forces on a band element (width = b)

Design Analysis Integrating Eqn. n over the length of contact gives: What is jiggering process? Jiggering is a motion in which the clay bat is formed by means of templates or rollers. The jiggering process is limited to axisymmetric parts and has limited dimensional accuracy. Automation of this process is necessary to improve productivity. The layered structure of clay can be formed with anisotropic behavior of the material both in subsequent processing and in the final properties of the ceramic products What is anisotropy? What is anisotropic behavior?

Design Analysis The maximum normal pressure pmax acting on the band occurs at ϴ = ϕ, where P = P1. Applying Eqns. l and m to this point gives: What is jiggering process? Jiggering is a motion in which the clay bat is formed by means of templates or rollers. The jiggering process is limited to axisymmetric parts and has limited dimensional accuracy. Automation of this process is necessary to improve productivity. The layered structure of clay can be formed with anisotropic behavior of the material both in subsequent processing and in the final properties of the ceramic products What is anisotropy? What is anisotropic behavior?

Design Analysis DIFFERENTIAL BAND BRAKE Attach fixed end of the band to the lever at the opposite of the pivot gives greater self-energizing action as shown in Figure 3. The force F for the differential band brake: What is jiggering process? Jiggering is a motion in which the clay bat is formed by means of templates or rollers. The jiggering process is limited to axisymmetric parts and has limited dimensional accuracy. Automation of this process is necessary to improve productivity. The layered structure of clay can be formed with anisotropic behavior of the material both in subsequent processing and in the final properties of the ceramic products What is anisotropy? What is anisotropic behavior? Figure 3: Differential band brake

Design Analysis PONY BRAKE TEST Used in determining brake power of the engine (esp. low power engine) What is jiggering process? Jiggering is a motion in which the clay bat is formed by means of templates or rollers. The jiggering process is limited to axisymmetric parts and has limited dimensional accuracy. Automation of this process is necessary to improve productivity. The layered structure of clay can be formed with anisotropic behavior of the material both in subsequent processing and in the final properties of the ceramic products What is anisotropy? What is anisotropic behavior? Figure 4: Pony brake test

Design Analysis PONY BRAKE TEST What is jiggering process? Jiggering is a motion in which the clay bat is formed by means of templates or rollers. The jiggering process is limited to axisymmetric parts and has limited dimensional accuracy. Automation of this process is necessary to improve productivity. The layered structure of clay can be formed with anisotropic behavior of the material both in subsequent processing and in the final properties of the ceramic products What is anisotropy? What is anisotropic behavior?

Design Analysis PONY BRAKE TEST What is jiggering process? Jiggering is a motion in which the clay bat is formed by means of templates or rollers. The jiggering process is limited to axisymmetric parts and has limited dimensional accuracy. Automation of this process is necessary to improve productivity. The layered structure of clay can be formed with anisotropic behavior of the material both in subsequent processing and in the final properties of the ceramic products What is anisotropy? What is anisotropic behavior?

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