DMK chain hoists and its accessories are produced by Donati Sollevamenti S.R.L.. These equipments conform ISO 9001 and UNI EN 29001 standarts and are also certified by ICIM

The modular conception of the electric chain hoists series DMK allows the assembly of the final desired solutions by choosing the standardized components suitable to the case.

PRODUCT RANGE

2S Hand-pushed configuration
Horizontal movement pushing the load . It is recommended for light duty and short load travel only

1F Fixed Configuration
Eyebolt suspension as a standard or hook suspension on repuest.

4 C Mechanically-operated chain trolley configuration
The hoists is operated by use of a chain that moves the trolley wheels and is controlled by the operator. This configuration is used in applications accomplishing a low number of cycles , when load travel is short , or when micro inching is required.


3 E Electrically-operated trolley configuration
This version is recommended when manual load pushing is not feasible and for heavy duty. The load is moved by the trolley which is controlled through the hoist pushbutton panel

MAIN COMPONENTS

REDUCTION GEAR
Epicyclic crown wheel with heat-treated high-strength steel gearing supported by oil-bath lubricated ball bearings. Noise level at full load is less than 85 db. The aluminum casing is finned externally for more effective heat dissipation by radiation

SELF-BRAKING ELECTRICAL MOTOR
The axial movement of the tapered brake ensures a fast braking action that remains reliable upon time accrual ( Ref.4.1.2.1 c "Machinery Directive '' ). Brake lining is asbestos-free. The motor is available in two versions: a single polarity version for one-speed hoists, and a double polarity version for two-speed hoists.

CHAIN
The chain is gauged and made of high-strength steel rod having an ultimate tensile strength of 80 kg/mm2 , and ultimate elongation higher than 10% .The applicable safety coefficient is always better than 5 ( Ref. 4.1.2.4 "Machinery Directive'' ). The heat and galvanising treatments applied to the chain ensure high resistance to wear , aging and corrosion.

LOAD SPROCKET
The load sprocket is heat treated and has five pockets. The pockets are machined by use of precision machinery. The sprocket drives the chain and ensures optimized chain motion.

CHAIN GUIDE (inserter-extractor)
This component provides for insertion and extraction of the chain links into and from the pockets of the load sprocket, both in ascent and descent (Ref. 4.1.2.6 "Machinery Directive'').

HOOK
The hookis made of high strength forged steel , is fitted with a safety device (Ref. 4.1.2.6 "Machinery Directive'') , and rotates on a thrust bearing.

REDUCTION GEAR WITH SELF-BRAKING MOTOR
This gear drives the trolley gears in the electrically-operated EM version
(Ref. 4.1.2.6 c "Machinery Directive'' ).

BOTTOM BLOCK
The bottom block is the joining element between the chain and the block. It is made of steel, and is equipped with a heat-treated large cross-section chain locking pin.

STOPS
The stops are installed on both the ascending and descending sectionsof the chain. They act as limit switches of hook travel (Ref.4.1.2.6 a "Machinery Directive"), and can be set as desired. They are made of forget steel, and are fitted with a damping insert.

CLUTCH
The clutch is an emergency device that repleces the traditional electrical limit switches as chain full up and down stops. It also operates as an overload protection (Ref.4.2.1.4 "Machinery Directive"), The clutch discs are asbestos-free, and are pre-loaded through a set of Bellevile washers.

CHAIN BOX
The chain box is available in several sizes as a function of hook travel. It is made of shock-resistant plastics and is fitted with suspensions which ensure freedom of movement.

BLACER
The balacer is connected to the clutch joint, and provides for correct hoist balancing. It absorbs the considerable heat generated during clutch operation.

TROLLEYS
The trolleys are used when loads are to be moved horizontally. They are identified with code DMT, and are available in the following versions:

TOWING ARM
The towing arm, which is the connecting element between the trolley and the power supply is avaible for all types of trolleys of the DMT series. It is adjustable in all directions and provides for power supply cable towing as needed to ensure that the cable is not torn.

LOW VOLTAGE (48V) ELECTRICAL CONTROLS
Hoist operation (hook ascent and descent) is commanded through these controls. They also command left-right travel of the trolley, when installed. The control system includes:

All the elecetrical components are certified. They are installed in a sealed box of protection leven IP55, made of polyamide-base resin. The box is secured t the hoist on the motor side, and is supplied with power at the mains voltage (220/380 V 50 Hz for series production models). The controls are operated from a low-voltage (48V) pendant pushbutton panel for enhancel operator's safety. The ergonomic pushbutton panel is made of shock-resistant and self-extinguishing plastic material, is sealed, and has protection level IP67. It is fitted with a mushroom-head start/stop pushbutton
(Ref.1.2.4 "Machinery Directive"). The same push button permits intentional machine start by means of a positive release feature (Ref.1.2.3 "Machinery Directive").
The pushbutton panel is connected to the electrical system through a multi-wire electrical cable fitted with anti-tear metal braid.