Calculation and Design of Cylindrical Gearbox

Contents

TABLE OF CONTENTS

DESIGN ASSIGNMENT

INTRODUCTION

CALCULATION AND DESIGN

I. Motor selection and kinematic calculation

II. GEARBOX GEAR CALCULATION

III. PRELIMINARY CALCULATION OF GEARBOX SHAFTS

IV. STRUCTURAL DIMENSIONS OF GEARS AND WHEELS

V. GEARBOX HOUSING DESIGN DIMENSIONS

VI. CALCULATION OF CHAIN TRANSMISSION PARAMETERS

VII. FIRST STAGE OF GEARBOX ASSEMBLY

VIII. VERIFYING THE DURABILITY OF PINCHES

IX INSPECTION OF KEYWAY CONNECTIONS

X. REFINED SHAFT CALCULATION

XI. FITS, TOLERANCES AND ROUGHNESS OF MAIN PARTS

XII. CHOICE OF OIL GRADE

List of literature

Introduction

Description of the design of the designed drive.

A reduction gear is a mechanism consisting of gear or worm gears, made in the form of a separate unit and serving to transfer rotation from the shaft of the engine to the shaft of the working machine .

The purpose of the reduction gear is to reduce the angular speed and, accordingly, increase the torque of the driven shaft compared to the driving one.

The reduction gear consists of a body (cast iron or welded steel), in which the transmission elements are placed - gears, shafts, bearings, etc. In some cases, the housing also houses means for lubricating the engagement and bearings (for example, a gear oil pump may be placed inside the housing) or cooling means (for example, a coil with cooling water in the housing of the worm reduction gear).

The reduction gear is designed either to drive a certain machine, or to a given load (torque on the output shaft) and gear ratio without specifying a specific purpose.

The most common horizontal gearboxes. Both horizontal and vertical gears can have wheels with straight, oblique and chevron teeth. Shafts are mounted on rolling or sliding bearings. The choice of horizontal or vertical circuit for all types of gearboxes is due to the general arrangement of the drive (relative arrangement of the engine and the working shaft of the driven machine, etc.).

The reduction gear designed in this course design complies with the terms of reference.

Gearbox classification specified in the assignment for course design:

1. by gear type: toothed;

2. by the number of stages: single-stage ,

3. by gear type: cylindrical.

A cylindrical single-stage reduction gear is a device for enhancing torque by reducing the number of revolutions by engaging gears. The advantage of this type of reduction gear is high efficiency, the ability to withstand large loads and transmit large power, as well as work under uneven loads, a significant number of starts and stops. It is also worth noting the high reliability due to the device of the cylindrical reduction gear, the lack of self-braking, low heat generation and a wide range of gear ratios, which expands the possibilities of using this type of devices in various machines and mechanisms. Disadvantages of this gearbox:

1. Many times more noise is produced during operation than cylinders, which are based on a worm drive.

2. The lack of work includes the lack of reversibility function, namely, self-braking.

Gearbox design meets technical and assembly requirements. The designs of many units and parts of the reduction gear take into account the features of large-scale production .

Standardization and harmonization were widely used in the work on the course project.

The gearbox housing is made detachable, cast from cast iron of grade SCH 15 GOST 141279. Reduction gear shafts are made of steel 45. Rolling bearings are used for shaft supports.