Magnet Schultz develops new landing door locks for safety conscious Hewden

Hewden, the UK’s largest equipment rental provider, is leading the way in the development of health & safety features on its goods only hoists with the support of Magnet Schultz, a specialist manufacturer of solenoids and electromagnetic devices. Magnet Schultz has designed and manufactured a fully mechanical interlocking door lock system for Hewden’s goods only hoists, which provide clients with unsurpassed safety whilst the hoist is in motion or between landings.

Goods only hoists are essential in the construction of high-rise buildings, enabling the transportation of heavy materials to multiple landings. The hoists are equipped with heavy duty sliding gates, which are operated by building labourers once the hoist reaches the required landing. With the old mechanism, accidents could occur if the landing gates had been opened whilst the hoist was in motion or had not reached the landing.

Already a requirement for its passenger hoists, Hewden wanted to implement the same levels of safety for its goods only hoists. As there was no propriety lock available, it approached Magnet Schultz to develop a new mechanism for its fleet construction goods only hoists whereby a safety switch would establish whether the hoist had reached the landing before allowing the gate to be opened.

Prior to beginning the process of designing the new locking device, Emessem Solenoid set about fully understanding the function of the existing system and its shortcomings.

From its investigations Magnet Schultz was able to determine that if the new lock could be manufactured as ‘plug & play’ unit, thereby making it quick and easy to install by non-specialist personnel, Hewden would no longer have to employ and wait for a qualified electrician to install the mechanical locking device. Other factors that Magnet Schultz needed to take into consideration were that the lock needed to be weatherproof, of a heavy-duty construction to cater for the harsh operating conditions and incorporate a safety switch and fail-to-lock alert.

Magnet Schultz also had to determine the interfaces with other parts of the system. This involved establishing both the switch and the push button operations, mimicking the proven heavy-duty locking beak into the new design and incorporating industry standard connectors for the daisy chaining of the landing locks.

With this essential work completed, Emessem Solenoid began the task of specifying the performance requirements of the assembly including function, electrical power consumption, mechanical protection and operating life. Key to this was the selection, adaptation and manufacture of a suitable shotbolt unit to form the centre core of the assembly. As part of the Magnet-Schultz Group, the world’s leading solenoid manufacturer, Magnet Schultz Ltd was in a unique position to develop the ultimate solenoid for the mechanism.

With the solenoid development completed, Magnet Schultz then turned its attention to designing and developing the assembly parts. This involved preparing detailed drawings and the preparation of models, manufacturing and testing prototypes for proving in the field through site trials and carrying out final assembly testing.

“Magnet Schultz is an extremely professional company that put in time and effort to understand our requirements and was able to design a mechanism that fully achieved our goals”, said Martin Brady, Service Manager at Hewden Hoists. “The company’s prototypes were thoroughly tested under extreme conditions and worked superbly. As the locks incorporate industry standard connectors they can be quickly fitted without us having to employ an electrician”.

Magnet Schultz has provided Hewden with a landing door lock system that meets its health & safety requirements. Such has been the success of the project and Emessem Solenoid’s technical understanding of the application that the company has been engaged by Hewden to begin work on developing a new shotbolt for another hoist gate system.