What are Gear Shaft Splines?
Splines are teeth or ridges on gear shaft which mesh with the grooves in mating pieces and they transfer the torque to these shafts. This helps in the maintenance of an angular correspondence between the teeth. They are used mostly in mechanical transmissions. Spur gears and helical gears could also be cut on to the gear shafts to provide a dual drive when needed in few industries.
Ø300mm. ; L=1000mm ; Nr. of teeth 4-36 ; Max module = 6mm
Customizing Splines on Shafts
Vestavia will be able to manufacture splines on the gear shafts that are cut traditionally on the gear cutting machines. The shaft and spline can be manufactured at one go to make sure that there is complete concentrically between them. Vestavia can manufacture both involutes and parallel key splines along with serrations as per the drawings of its customers. The reason why splines cannot be rolled on to the gear shafts is because this process is usually associated with volume production of a mass nature.
Spacing of the Teeth of the Splines
A splined shaft will always have teeth that are spaced equally around a circumference that is parallel to the axis of rotation of the gear shaft. These teeth could be made either sided or straight and they can be formed as involutes or serrations. The external splined shaft can be made to mate with internal splines which has slots or spaces that are formed for mating to the teeth of the shafts. The rotation of these splined shafts will be transferred to internal spline members like gears or similar rotary devices.
The connection for the splines will offer a load that is distributed equally along the sides of its teeth. The load is shared and it will provide longer life of fatigue as against a keyway drive in the process of broaching. For example, a gear that is mounted on shafts may utilize male splines on those shafts that match the female splines on the gears. They can be matched in the center of the clutch plates while the smooth tips of their axles will be supported in the pilots that bear in the flywheel. The alternative method to splines is a key and a key way but it is the spline that offers a bigger fatigue life for the gear shaft.
Types of Splines
There are two major kinds of splines – they are external and internal. External splines can be broached and shaped on gear shaping machines; they can also be hobbed, milled, rolled, extruded or ground. The range of methods that are available for the manufacture of internal splines is limited as a result of restrictions of accessibility. In the case of internal splines, the splined parts may not carry a through-hole that will preclude utilizing a push and pull extrusion-type or a broaching method. If the parts are of a smaller size. It may be tough to fit grinding or milling tools into those areas where the splines have been machined.
Splines are always used in rotating drive systems of a mechanical kind. Devices which transfer rotary motion from one input gear shaft on to an output gear shaft will use splines of one type or another. The types may include –
Parallel Key Splines
– They have teeth that are spaced equally and they are all straight-sided. The teeth on the shafts have an equal thickness in terms of teeth at any point that is measured at the radial out from the rotational axis. On the other hand, internal parallel splines have parallel spaces.
– They have teeth that are spaced equally but they do not have straight sides. The teeth project an in-volute form which is akin to an in-volute gear tooth.
– These types of splines have teeth that are non-involution. The teeth of male splines are in the shape of an included angle. With female serrations that have spaces of a similar included angle.
Methods used for Manufacturing Splines and their Applications
- Broaching – This method is used in the manufacture of female splines of all kinds. The broach tool is selected specifically to internal splines that it is specially designed for.
- Hobbing – All the external splines can be manufactured with this method. Based on the restrictions of machine tools and the particular component designs.
- Shaping – This method is used in the manufacture of internal and external splines of in-volute, parallel or the serrated kind.
Vestavia manufactures a vast range of gear and spline shafts for numerous industries. Typical uses of splines are in steering units of the heavy duty kind for both commercial and the earth-moving vehicles. They are also used commonly in power brakes. Commercial winches and classic vehicles and in various other industries that need drive systems which are positive.
The common practices involved in the process of gear cutting are broaching, hobbing, milling and grinding. Our gear cutting operations will take place either later or as a substitute for the forming processes like extruding, forging, sand casting or investment casting.