Doğrusal Profil Modifikasyonlarının Bir Düz Dişli Çarkın Dinamik Yüklenmesi Üzerine Etkisi

Dişli dinamiği, titreşim seviyeleri, yük taşıma kapasitesi ve gürültü üzerindeki dikkat çekici etkisi sebebi ile dişli tasarımındaki en kritik konulardan birisidir. Uç modifikasyonu, endüstride dinamik yükleri azaltmak için basit bir yöntem olarak bilinmektedir. Bu çalışmanın ana amacı da doğrusal profil modifikasyonlarının düz dişli çarkların dinamik davranışına etkisinin anlaşılmasıdır. Bu kapsamda, kavrama süreci ve dişli kavrama rijitliği hesaplama yöntemi tanımlanmıştır. Düz dişli çark çiftinin dinamik cevabını bulmak için iki serbestlik dereceli bir dinamik model oluşturulmuştur. Simülasyonlar, standart ve farklı miktarlarda uç modifikasyonuna tabi tutulmuş düz dişli çark çiftleri ile gerçekleştirilmiştir. Uç modifikasyonunun dişli çark dinamik cevabı üzerinde mükemmel bir etkiye sahip olduğu görülmüştür. Ancak, bu etki belirli bir miktar ile sınırlıdır. Optimum uç modifikasyonu miktarından sonra, dinamik yükler önemli ölçüde artmaktadır. Bu çalışmada, dişli çark tasarımcıları için MATLAB® programında optimum uç modifikasyonu miktarını bulmak için bir bilgisayar programı geliştirilmiştir. Program çıktıları iki farklı vaka için verilmiştir.

Anahtar Kelimeler:

Dişli Dinamiği, Uç Modifikasyonu, Düz Dişli, Kavrama Rijitliği

INFLUENCE OF LINEAR PROFILE MODIFICATIONS ON THE DYNAMIC LOADING OF A SPUR GEAR

Gear dynamics is one of the most critical subjects in gear design because of its remarkable effect on vibration levels, load-carrying capacity, and noise. The tip relief modification is known as a simple method to decrease dynamic loads in the industry. The primary goal of this study is to understand the influence of tip relief modification on the dynamic performance of the spurs gears. In this paper, the meshing process and gear mesh stiffness calculation method are defined. A dynamic model with two-degree-of-freedom is created to find the dynamic response of the spur gear pair. The simulations are carried out with standard and different tip modified spur gear pairs. It is observed that the tip relief modification has an excellent effect on the gear dynamic response. However, this effect is restricted until a certain amount of tip relief modification. After the optimum amount of tip relief modification, the dynamic loads are increased considerably. Thus, a computer program is developed to find the optimum amount of tip relief modification in MATLAB® for the gear designers. The program outputs are given for two different case studies. As a result of the study, the dynamic factor behaves like a “V form” according to the tip relief modification, and the dynamic force decreased approximately 25% for optimum profile modification.

Keywords:

Gear Dynamics, Tip Relief, Spur Gear, Mesh Stiffness,

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