Shimizu Construction Co., Ltd. (President Kazuyuki Inoue) recently jointly developed the construction elevator "SEC-5000RS" with Sanko Kenki Co., Ltd. and S. C. Machinery Co., Ltd., which has the highest vertical transportation performance in Japan and further improves the efficiency of lifting operations that determine the construction period of high-rise buildings. The first unit is already in operation in the construction work in the Nihonbashi 1-chome Chuo District, and the second and third units have been determined to be applied to the construction of the Torch Tower, which will be the tallest building in Japan.

Efficient transportation and movement of equipment and workers are essential for the efficiency of high-rise building construction. A construction elevator is the key to on-site logistics in such construction sites. On the other hand, in high-rise building construction sites, there are often long queues of workers in front of elevators after morning meetings or during break time, and there are also many cases of transportation with light loading capacity despite the weight loading restrictions. Therefore, we have been developing construction elevators with large capacity and variable speed control functions to address these issues.

In the development process, reducing the noise from the drive unit, which has been made high-functioning to accommodate large capacity and variable speed control, was a challenge. The noise source is vibration transmitted from the drive unit installed in the lower part of the elevator to the elevator, so we devised a new system that separates the two and suspends the elevator from the drive unit, and also equipped it with anti-vibration functions to make the elevator vibration-resistant. As a result, the noise level has been reduced from about 90 dB (elevated level) to about 80 dB (inside a train), which is lower than the current general construction elevator (maximum load capacity of 3.0 tons).

The specifications of the SEC-5000RS were designed to be suitable for high-rise office buildings with high floor heights, achieving an internal dimension of 5.8m × 2.16m × 3.0m (width × depth × height) and a maximum load capacity of 5.0 tons, resulting in the highest vertical transportation performance in Japan. As a result, compared to the 3.0-ton type, the floor area of the elevator has increased by 1.6 times, to 12.53m2, which is equivalent to 6 boards in terms of loading capacity, and can accommodate about 1.7 times more workers, approximately 76 people. The lifting speed has been increased by 10% to a maximum of 110 m per minute through the high-functioning drive unit. With variable speed control, the lifting speed changes to 110 m per minute for load capacity of 0-3t, 100 m per minute for 3-4.5t, and 90 m per minute for 4.5-5t, allocating the surplus power generated by the drive unit during light loading to increase the lifting speed.

In the joint development, our company was responsible for the planning and setting of the basic functions, performance investigation of the actual machine, Sanko Kenki Co., Ltd. was responsible for the basic design and production of the experimental device, and S. C. Machinery Co., Ltd. was responsible for the consideration and experimentation of the specifications.

In the future, there is expected to be an increase in orders for the construction of high-rise buildings, mainly in major metropolitan areas. Our company plans to improve the efficiency of high-rise building construction by horizontally expanding the SEC5000-RS, aiming to enhance our competitiveness in bidding and increase profitability, and continues to work on improving on-site logistics efficiency.