2.1. General description of new engines of the L8, LF and L3 models
|Fig. 2.1. Chart of dynamic characteristics of engines of the Mazda 3 car
On the Mazda 3 car modern engines of new generation with improved dynamic and maintainable характеристикми are established. The L8 engine – working volume of 1,8 l, Max. capacity – 88 kW (120 h.p.), Max. it is abrupt. the moment – 165 N · м/4300 mines-1
of 197 km/h gathering the maximum speed. The LF engine – working volume of 1,8 l, Max. capacity – 104 kW (141 h.p.), Max. it is abrupt. the moment – 181 N · м/4100 mines-1
, 208 km/h gathering the maximum speed. The L3 engine – working volume of 2,3 l, Max. capacity – 122 kW (166 h.p.) Max. it is abrupt. the moment – 207 N · м/4000 mines-1
, 214 km/h gathering the maximum speed. The L3 engine can be supplied with a turbokompressor – Sequential Valve Timing (S-VT) system. The principle of action of a turbokompressor is that the drive of a turbokompressor works thanks to energy of the burned-down fulfilled gases. The compressor consists of two axial lopastny wheels. The hot fulfilled gases get to the turbokompressor case where untwist a driving (first) wheel to frequency of rotation of 100 000 mines-1
. The driving wheel, in turn, untwists the second lopastny wheel which pumps air in the compressor by means of a shaft and submits it to the combustion chamber. The warmed-up air which has passed through a turbokompressor is cooled in a radiator of soaked-up air. Cooling also provides a bigger gain of capacity (fig. 2.1)
|Fig. 2.2. General view of engines of the Mazda 3 car
The Mazda company brought a number of technical improvements in a design and technical components of new engines.
For example, on engines of the L3 model the mechanism of change of phases of a gazoraspredeleniye is applied. With a view of reduction of lump of the car the block of cylinders on new engines is made, as well as a head of the block of cylinders, from an aluminum alloy.
Big changes are brought in a constructive and mechanical part of engines for the purpose of reduction of vibrations and noise level. So, for example, on engines of the L3 model the balancing block of cassette type is applied. On all engines the silent chain of a drive of the mechanism of a gazoraspredeleniye now is established. The block of cylinders is supplied with a long skirt of the piston and the integrated cover of radical bearings. Besides, on all engines the pulley of a cranked shaft with a damper of krutilny fluctuations and a suspension bracket of pendular type is applied.
It is simplified, with a view of maintainability improvement, a contour of a belt of a drive of auxiliary units. Now one driving belt is applied to all auxiliary units of the engine. The tension of a driving belt is regulated by an automatic natyazhitel. The cover of a forward part of the engine has an opening for carrying out maintenance (for an unblocking of a ratchet of adjustment of a chain and fixing of the lever of a natyazhitel).
As the power plant in Mazda 3 cars 4-cylinder engines in which cylinders are located in one row are used. From below the engine is closed by the pallet forming a case which at the same time is the tank for the oil necessary for greasing, cooling and protection of details of the engine from wear.
All three engines 16-klapanny, having on four valves on one cylinder. Valves are put in action by two camshafts located above through tarelchaty pushers.
Greasing of the engine is provided by the oil pump established on the face party of a case and put in action from a cranked shaft. The oil which is soaked up from the oil pallet, moves through openings and channels to bearings of cranked and distributive shaft and to working surfaces of cylinders.
Preparation and giving fuel - an air mix are carried out by the electronic control system of the engine which is not demanding service.