Press-insertion system in combination with suitable feeding machines

Press-insertion devices for handheld and stationary assembly tasks

If you have ever punched a hole in a cover or pushed a tack or pin in a wall then you will know how much stress it causes your thumbs. It can be painful if your thumb is strained like this repeatedly over time. There are many applications in industrial production where it is often left to workers to push together fastening elements by hand in order to attach two components. Fitters may repeat the movements hundreds of times per day. For automotive assembly, interior trim is predominantly attached using trim clips, plastic expanding rivets or push-fit panel pins. These fasteners have one thing in common: They must be pressed into a pre-drilled hole to connect two components together. Press-insertion joining processes can be found in many other sectors as well as the automotive industry: from the aviation and aerospace industries or machine building, telecommunication and apparatus engineering up to modular assembly for electronics and vehicle technology.

In order to make the positioning and placement of fastening elements more ergonomic for fitters and to make the assembly process more efficient, manual work stations can be equipped with manually-operated press-insertion devices. These tools support operators, making the process simpler by using an insertion stroke for press-in procedures. In addition, any attachment points which are difficult to access, can be reached more easily using the tool rather than using fingers. The specialists for automated feeding and screwdriving technology, DEPRAG SCHULZ GmbH from Amberg, Germany have developed two press-insertion devices for handheld use: Type EDG with an insertion stroke and type EDGZ with an insertion stroke and additional locking stroke. Both devices are characterised by the convenient ergonomic shape of the handle. The operator guides the entire downstroke of the press-insertion procedure when using type EDG. The pressure exerted by the operator supports the down-pressure. Whereas when using type EDGZ, the operator only effects a short insertion stroke necessary for actual press-insertion. An integrated cylinder performs the locking stroke ensuring that pressure is kept directly on the fastener as it protrudes from the nosepiece. The fastener has no space to retract.

In addition to the manual press-insertion devices, DEPRAG also supplies stationary press-insertion modules. In stationary applications, both the feed and insertion strokes are carried out by cylinders. Sensors, which recognise the features of varied fasteners, can be used to realise innumerable applications, processing rivets, pins, sleeves and balls, as well as asymmetric components. The press-insertion module can also be enhanced with integrated depth sensors, presence monitors and position controls, thereby creating a versatile complete solution for complex assembly applications.

One specific advantage of DEPRAG press-insertion devices and modules is the option for integration into a complete press-insertion system, in combination with a suitable DEPRAG feeding machine. These machines feature outstanding efficiency and reliability as well as shortened cycle times. Positioning and loading procedures can be carried out quickly and reliably either by hand or in an assembly system.

DEPRAG press-insertion systems consist of a handheld press-insertion device or stationary press-insertion module, a maintenance unit, an electronic controller and a feeder. Select either a vibratory spiral feeder or a sword feeder allowing the nosepiece ball-type or split-type to be specifically tailored to the application and fastening element. Sword feeders are particularly suitable for applications which require gentle handling, low-friction and a quiet noise level. Standard DEPRAG sword feeders are available with bowl sizes 0.15 l and 1.5 l. The feeders are especially suited for the processing of size M2 to M6 screws with a maximum shaft length of 25 mm, as well as for cylindrical pins, rivets and balls with a diameter of 1 to 12 mm.

For the processing of screws, threaded pins, nuts and o-rings, a vibratory spiral feeder is recommended. DEPRAG offers a particularly energy efficient feeder in their "eacy feed" product. The "eacy feed" drive uses 24 V vibratory magnets which significantly reduce maximum power consumption, enabling an energy saving of approx. 80 percent. The 24 volt technology guarantees reliable operation even with an inferior mains supply – regardless of supply voltage or frequency. The universal power supply enables worldwide application. Furthermore, the "eacy feed" is communicative and prepared for application in an Industry 4.0 concept. The spiral feeder is suitable for screw sizes smaller than M1 up to M8, with shaft lengths of 5 mm to 60 mm. There are four standard bowl sizes available for "eacy feed" handheld devices and seven for stationary operation.

Whether in complex automated production in assembly systems or manually-operated handheld press-insertion devices – both DEPRAG feeding machines supply conveyed parts precisely and reliably at high feed rates. The combination of feeder and press-insertion device or module as an adaptive press-insertion system provides an attractive complete solution for diverse assembly applications. DEPRAG has been developing this technology over decades and further enhancements are continually being made. All basic key technologies originate in-house and are therefore optimally coordinated with one another. The press-insertion of grooved pins to attach child seat covers, positioning of steel rivets to enable subsequent riveting or press-insertion of expanding rivets to attach circuit boards to housing frames are just some examples of applications which have already been realised.