Heading operation worm gear box

Contents

INTRODUCTION

1 Kinematic and power calculation of the drive

2 Calculation of gears

2.1 Worm Gear Calculation

2.2 Calculation of V-belt transmission

2.3 Calculation of chain transmission

3 Calculation and design of shafts

3.1 Preliminary calculation of shafts

3.2 Check calculation of shafts

3.3 Shaft from electric motor

4 Calculation of key connections

4.1 High speed (input) shaft

4.2 Slow-moving shaft

5 Calculation and design of bearing units

5.1 Check calculation of rolling bearings

5.2 Check calculation of rolling bearings

6 Design of gears and pulleys

6.1 Design of worm gears

6.2 Design of V-belt pulleys

6.3 Design of Drive Sprockets

7 Construction of housing parts and covers

7.1 Design of Housing Parts

7.2 Design of Bearing Covers

8 Lubrication of hooks

9 Frame Design

10 Selection of fits

11 Gearbox assembly and adjustment

12 Safety precautions

CONCLUSION

LIST OF RECOMMENDED LITERATURE

Introduction

Worm reducer is one of the classes of mechanical reducers. Gearboxes are classified by type of mechanical transmission. The gearbox is called worm-like in the form of a worm gear located inside the gearbox, transmitting and converting torque. The screw that underlies the worm gear looks like a worm, hence the name. Worm gear can be provided with one or more mechanical planetary gears.

The diagram shows an electric motor, a worm gear and a chain drive. It is necessary to calculate the worm gear and chain gear.

Gearboxes are classified according to the following main features: gear type (toothed, worm or gear-worm);

number of stages (single-stage, two-stage, etc.);

to type of cogwheels (cylindrical, conic, konicheskotsilindrichesky, etc.);

relative location of gear box shafts in space (horizontal, vertical);

peculiarities of kinematic scheme (unfolded, coaxial, with bifurcated stage, etc.).

Gearbox assembly and adjustment

An example of an assembly of a worm gear box with vertical shafts is given. Prior to assembly, inner parts of body parts are cleaned and covered with oil-resistant paint. Before the general assembly, shafts with fitted parts are assembled. Left bearing, bushing, worm wheel, right bearing are put on slow-moving shaft. Assembled shaft is inserted into casing hole. Bearings are heated in oil before assembly. Then a gear wheel is put on the shaft. The right bearing is successively put on the high-speed shaft, the sleeve is inserted into the housing and fixed, the shaft is inserted into the sleeve, the left bearing and bushing are put on. All parts are fixed in axial direction by splined nut. The reduction gear box housing together with installed shafts is installed on the base and fixed with bolts. The cover of the housing is put on top of the reduction gear case and fixed with bolts. Bearing covers are put on the sides of the shafts, which are attached to the housing with screws. Prior to installation, collar seals pre-impregnated with oil are inserted into the grooves of bearing covers. Then adjustment gaskets (set) are put on bearing covers. Assembled covers are inserted into housing sockets and attached to it.

After assembly the gear box is adjusted. Adjustment of bearings is performed by a set of adjusting gaskets installed between the housing and bearing covers, as well as by splined nut on high-speed shaft. Adjustment of low-speed shaft bearings consists in creation of clearance between end face of external ring of bearing and end face of bearing cover. The required clearance is obtained by adjusting the thickness of the adjusting gaskets.

Adjustment of high-speed shaft bearings consists in creation of preliminary tension in bearings (displacement of the external ring of the bearing relative to the internal one) due to screwing or unscrewing of the splined nut and subsequent locking of it with a locking multi-flange washer.

In the assembled gearbox, the high-speed shaft must rotate freely. The oil outlet plug is twisted and an oil indicator is installed. Oil is poured. The assembled reduction gear is rolled.

Safety precautions

When illuminating safety issues during installation and during operation of the reduction gearbox, it is necessary to pay attention to the following measures.

Provide reliable attachment of electric motor and reduction gear box to frame and frame to foundation.

Rotating parts (inlet and outlet ends of shafts, couplings) must have a protective casing.

Belt, chain, open gear and worm gears shall be enclosed (with sheet metal casing or fine metal mesh).

Electrical wires shall have a protective shield (passed through the tube).

The wire ends (motor supply) shall be insulated and covered by a cover.

The unit must be grounded.

The frame after locksmithing and welding shall not have burrs.

Inspection of engagement, adjustment, rectification of faults and assembly and disassembly operations is required only when the electric motor is switched off.

Do not touch rotating parts during operation. Perform maintenance at complete shutdown of the electric motor.

Regularly monitor the oil level in the gearbox and monitor the presence of lubricant in the bearings.

Prevent persons who have not been trained in safety and maintenance of the gearbox.

During maintenance, installation and dismantling use only serviceable tools.

Conclusion

In this course design, using the initial data, a drive is designed according to a given scheme, consisting of an electric motor, a V-belt transmission, a worm single-stage reduction gear and a chain transmission.

During the course project, the kinematic and power calculation of the drive, the calculation of gears, the calculation and design of shafts, the calculation of key joints, the calculation and design of bearing units, the design of gears and pulleys, the design of body parts (cups and covers), the lubrication of hooks, the design of the frame, the selection of fits, etc., were carried out.

It also studied the basis of calculation and design of parts and assembly units taking into account rational selection of materials, technology of manufacturing and operation of the machine.