Short delivery times for feeding technology

Vibratory spiral feeders and sword feeders delivered swiftly

It is a trend which began in the 80s and has continued to the present generation, almost becoming the accepted standard: vehicle manufacturers are bringing a growing number of models onto the market in increasingly fast succession. This has a noticeable impact on product development and production. There is particularly high demand for concepts which shorten the development period. For instance, one efficient method is to plan, design and order production systems and resources parallel to the development phase of a new car model rather than subsequently. Therefore, any alterations which may arise during product development have a direct influence on production resource planning, which consequently may need to be adapted. A suboptimal flow of information, as a consequence of multiple organisational interfaces, can increase the scope and complexity of required alterations and lead to delays in the overall development time. In this case, there is particularly high pressure for punctual completion of the system in order for production to start. Short delivery times, sound planning and reliable partners and suppliers for every single system component have a heightened significance because system construction must adhere to the project schedule.

Alongside the planning and layout of screwdriving tools, the focus of screwdriving assembly system designers is on another important component: the feeding technology. This is because the required feeding device is an essential part of the assembly process, and crucial for the productivity and reliability of a screwdriving assembly system. The type of feeding system and the necessary device depend on the quality and composition of the fasteners. If rotationally symmetrical components are used, such as screws, nuts and rivets, then the vibratory spiral bowl feeder and sword feeder are the best option.

Modular design and standardisation are optimal pre-requisites for saving execution time in system building. DEPRAG SCHULZ GMBH u. CO. from Amberg, Germany, specialists in automated feeding and screwdriving technology, are themselves active in system construction and have over four decades of experience in designing manifold feeding systems for handheld and stationary use. With the knowledge they have gained, the company have developed a sophisticated, comprehensive modular standard system. This enables DEPRAG to guarantee 8 weeks delivery time for standard version vibratory spiral feeders and sword feeders. "We are able to configure, rather than design, standardised feeding devices as we draw from our modular construction kit. Most of the components, such as standard sized feed bowls with pre-fabricated spiral geometry, housing, controllers, valve blocks, assembly plates and standard length feed hoses are amply available in stock and only need to be adjusted and assembled", explains Dipl.-Wirtsch.-Ing. (FH) Robert Bachmeier, Sales Manager (Germany) at DEPRAG.

All technical data relating to feed parts and the component to be assembled are required for the precise design of a standardised feeder. In addition, the required cycle time, selected controller version and the necessary fill volumes are needed. "Based on these benchmark parameters, the customer receives a customised quotation exactly fitting their specifications. The 8 week delivery period begins as soon as an order is placed and all informational details required for design are made available", clarifies Bachmeier.

Project specific design work is usually limited to the grinding of a suitable feed track in the feed bowl and the adjustment of the nosepiece according to screw and component geometry. Then the spiral or sword feeder is assembled at DEPRAG and put into operation. Each device is subject to a comprehensive test procedure before delivery to the customer. If possible, as well as a continuous test, this also includes a simulation of the customer specific working process. "In order to carry out this test we generally need a quantity of sample screws to fill the capacity of the feeding system and a sample of the component part", explains Bachmeier. After the internal functional test, a commissioning protocol is generated which confirms adherence to the necessary performance parameters. "We recommend that our customers are present at the handover if possible. This is a good opportunity to exchange information relating to recommissioning, operation and maintenance of the feeder. Another benefit which incidentally does not cost any extra", adds Bachmeier.

DEPRAG feeding machines are characterised by their fast, uncomplicated commissioning as well as simple integration and operation. The designers can choose from three different controller versions. In the basic version "O" only the standard control unit is integrated. "P" devices have valve blocks as well as pneumatics and "EP" devices include the electronic sequence controller as well as the pneumatics – the operator just sends a 24 V signal.

The standardised system modules of the DEPRAG spiral feeders and sword feeders have been continuously improved over decades of development. For the vibratory spiral feeder "eacy feed" for example, there are standard version feed bowls for manual use in four different fill volumes: 0.15 l, 0.75 l, 1.2 l and 2.5 l. The spectrum of devices is suitable for screws smaller than M1 to M8 and shaft lengths from 5 mm to 60 mm. It is particularly noteworthy that the "eacy feed" is tremendously energy efficient: Using 24 V oscillating magnets power consumption is significantly reduced, leading to an energy saving of approx. 80 percent. The 24 V technology additionally enables worldwide application of the "eacy feed" and guarantees reliable operation even with an inferior power supply. Furthermore the "eacy feed" is communicative and prepared for application in an Industry 4.0 environment.

Sword feeders, also known as segment feeders, are one alternative to vibratory spiral feeders. They are used when feed parts need to be handled particularly gently, quietly and with low abrasion. DEPRAG sword feeders are available as standard with bowl sizes 0.15 l and 1.50 l. They cover screw sizes M2 to M6 and are ideal for screws up to a maximum length of 25 mm. They can also be used to feed balls with a diameter between 1 and 12 mm.

Alongside their spiral feeders and sword feeders, DEPRAG offers an expansive range of alternative feeding technology options: linear conveyors, pick-and-place procedure, tape-on-reel / belt reel feeders, screw presenters and supply systems. These options also predominantly utilise modular construction kits. For the most part, these customer specific designs also rely on pre-fabricated standard modules thereby once more enabling short delivery times.