New Halder standard parts for workpiece clamping
Positioning clamping pins allow repeatability of ±0.03 mm
Simple handling, flat construction height, minimal wear
So that new possibilities for economic production are constantly being provided to users in the different industries and in order to further improve workpiece clamping, Erwin Halder KG believes in the continual development of innovative standard parts. "Workpiece clamping is a crucial factor in terms of efficiency. Straightforward handling, for example, can reduce set-up times. Standardised solutions which are not designed for just a single workpiece but which can be used in diverse situations also save procurement and storage costs. These are just two factors which we take into account for the constant development of our standard parts for workpiece clamping," according to Bernd Janner, Sales Executive at Erwin Halder KG. The positioning clamping pins are amongst the latest developments. They ensure fast clamping, fixing, adjusting, changing and securing of workpieces, plates as well as fixtures.
Simple set-up, reliable clamping
The positioning clamping pin consists of a clamping screw, the actual clamping pin, an O ring and spring pre-loaded spherical clamping segments. It is available in both blackened heat-treated steel (1.4542) and precipitation hardened stainless steel in the diameters 16, 20, 25 and 30 mm. The clamping pin is inserted into the suitable locating bushing from above. Tightening the clamping bolt then presses the four balls located in the pin outwards against the inner wall of the locating bushing. Because the diameter of the bushing tapers towards the top, the pin then sits centrally and is securely fastened. "In this way, for example, a clamping with a jaw vice can be positioned and released again with a flick of the wrist. This allows a fast change, for example, between the machine and measuring device," adds Bernd Janner.
To operate the clamping bolt, there are two possibilities: with a hollow hexagon wrench or with a detachable handle made of stainless steel. This allows simple and fast operation of the positioning clamping pin without additional tools. It is fastened to the positioning clamping pin with an M4 screw. To facilitate handling, spanner flats and knurls are attached.
For precise clamping with optimal repeatability, the user should install two central and two floating bushings in the plate to be clamped, through which the clamping pin is pushed. To distinguish between them, the floating bushing has an identification groove. The suitable locating bushings are installed in the base plate or machine table. The pin is clamped and positioned in these. There are two types of locating bushing. The screw-on type is put in the positioning holes of the machine table or the base plate, and they is then fixed with three screws. The pressing-in type, however, is simply attached by applying light pressure. The bushes are available in blackened, case-hardened steel as well as in hardened stainless steel (1.4112).
The Sales Executive, Bernd Janner, emphasises the high repeatability of the system: "When clamping the workpieces, the distance between the centres of the positioning holes in the machine table and in the clamping plate must be to a tolerance of 0.01 mm. In addition, two centring bushes are required centrally. This allows repeatability of of ± 0.03 mm to be achieved.
Many benefits thanks to spring pre-loading
As well as the high degree of precision, the positioning clamping pins have many other benefits: They are abrasionresistant and exhibit only minimal interfering contours thanks to their flat, compact construction. The spring pre-loading protects the clamping balls and locating hole from being overloaded and prevents the pin from jamming due to overstressing of the clamping bolt. In addition, it dampens vibrations upon chip removal.
Bernd Janner "With the positioning clamping pin we are taking other step towards clamping workpieces, plates and fixtures even more efficiently. It allows fast changing and is simple to handle. Therefore, we have also applied for a patent for the positioning clamping pin."