Conical locators, as their name implies, have a conical, rather than cylindrical, shape. Like cylindrical locators, small conical locators are usually called pins. Larger diameter locators are often called plugs.
Locating is an essential responsibility for a jig or fixture. The proper selection of locators contributes to the overall operation and accuracy of the workholder.
Carr Lane Mfg. is recognized as a world leader for standard tooling components and industrial parts. We offer cone locator pins and cone locator bushings for a variety of workholding applications. Learn more about conical locators in this guide from our engineering experts.
How Do Conical Locators Work?
Conical locating pins can be used for quick assembly of two fixture pieces, because they compensate for considerable misalignment. The pin's shank diameter and the bushing's OD are the same size. This is to allow boring the installation hole in both fixture pieces at the same time for greater accuracy.
These locators are mainly for locating holes that have large variations in their diameter. Conical locators are often used for cored, cast, or flame-cut holes. The locators may be part of a clamp and used on two sides, as shown below:
Conical locators are often used to locate holes with large diameter variations.
The main problem with using this type of locator is in the position of the workpiece relative to the workholder. The locating hole can contact the locator at any point on its conical surface. So slight differences in the hole diameter affect the workpiece height, as illustrated in Figure 7-16. This vertical height variation must be considered in the design of the workholder.
The height of a workpiece loaded on a locator is affected by the diameter of the locating hole.
Using Conical Locators Externally
Conical locators can also serve as external locators, contacting a workpiece on an external surface. As shown below, conical locator contacts the external surface of a cylindrical workpiece, its outside diameter.
Although usually used for locating holes, conical locators can also locate parts on external diameters.