Result Show the Effectiveness of the Transmission dirve

A series of tests of effectiveness of industrial gears were conducted by a team of Belgian researchers, catalogs doubts about the accuracy of the effectiveness versed in the issues of the transmission manufacturer. Researchers from the University of Ghent, tested more than a dozen devices and found that the measured yields of 25% to 11% worse was better than specified by the manufacturers in their catalogs values.

The double reduction gear reducer were up three steps, denoted by 0.34-5.58kW, 167-505Nm couples and conditions from 11.41 to 87.65. According to the researchers – that the results of the conference in Helsinki EEMODS reported last year – there is no standardization in the measurement of the efficiency of the transmission. Test of the transmission came from six unnamed manufacturer and covers a variety of technologies, including rectangular worm, bevel, worm and helical spiral-boxes, and a right helical field. The researchers used for their tests, an nm 1000, 3000 rpm platform worth 0.12-15kW. You installed torque sensors at the inlet and the outlet of the test transmission which was driven by a motor and used to drive a second motor (load) through a transmission reduction gear. They claim that their results are accurate to ± 1%. Manufacturers usually do not give information about the conditions in which they test their equipment, so different manufacturers’ efficiency values ​​can not be directly compared. Transmission inefficiencies caused by a combination of losses, including the seals and bearings and the lubricant churning. They are assigned the factors involved, such as design, performance and the ratio of the transmission and the number of floors.
One of their conclusions is that the efficiency fall at partial loads, the effect being strongest for low power transmission with high ratios. They also compared three gears with different technologies from the same manufacturer and found that a bevel gear at a right angle to the same efficiency was (95.5%) than cant box – but cost nearly three times more. A box of screws from the same supplier had an efficiency of 91.5%. Another factor in the transmission efficiency, temperature and the type of lubricant used can affect. Belgian researchers found that increased with Teflon powder addition with an "energy efficiency" lubricant with the effectiveness of a bevel gear reduced by 2% (relative to the standard oil), but the efficacy of screw worm gear by 15%.
As an example of how the results could be applied, Belgians cite the example of a torque of 200 Nm, 20rpm drive belt. Using a four-pole motor 0.75 kilowatts with a yield of 72% of the belt by means of a worm gear screw with a ratio of 72.5 and to drive a 69% yield , the efficiency of the system would be 50%. If an eight-pole motor 0.55 kilowatts with a yield of 66% was used instead, via a gear belt worm drive with a ratio of 37.5 and a yield 85% would be the effectiveness of the system amounted to 56% – an increase of 6%.

The researchers also found that the effectiveness of a bevel gear with three floors of another manufacturer is 95% – up 17% compared to a worm gear screw two floors by the same company (both valued at 0.34-0.39Nm and 180-190Nm). They say more work is needed in this area. The researchers acknowledge that there are occasions where self-locking characteristics of a worm gear screw are preferred.
If possible – include Belgian researchers suggesting that, to achieve the highest possible efficiency, users must select a bevel gear with such a ratio as low as possible.