Mitsubishi Heavy Industries Machine Tool Co., Ltd., a group company of Mitsubishi Heavy Industries, Ltd. (MHI) based in Ritto, Shiga Prefecture, will offer expanded services in metal 3D printing services commencing on July 15, including prototype production and contract production by metal 3D (three-dimensional) printers applying laser-based Metal Additive Manufacturing (AM) technologies. In addition to its previously offered Directed Energy Deposition (DED)(1) type metal 3D printers for large-scale parts, the Company will newly add services using binder jetting (BJT)(2) metal 3D printers for small-scale parts. The expanded service lineup will enable manufacture of a full range of metal parts, from small components of 1mm size to ultra-large-scale parts exceeding 1 meter.
“DMP2500” developed by Digital Metal
The addition to MHI Machine Tool’s lineup is the DMP2500 metal 3D printer developed by Digital Metal, a group company of Hoganas of Sweden. The DMP2500’s BJT technology not only enables extremely precise manufacturing but also is engineered especially for high-volume production. Currently, MHI Machine Tool has provided metal printing services applying unique DED technology of “LAMDA” AM systems; now, with the introduction of a different type of printer, the Company can respond to a broad range of metal 3D print needs and propose and provide the optimal manufacturing method and equipment for each parts.
MHI Machine Tool concluded a contract with Digital Metal in July 2020 on marketing its DMP2500 and other metal 3D printers in Japan. By adding these BJT type systems to its own sales lineup, MHI Machine Tool will be in a position to offer a broad portfolio of not only sales but also after-sales services.
While metal 3D printers are receiving attention for their innovative advances to production processes, they also present challenges relating to the difficulty of their production and quality assurance, etc. With the new expansion of services, MHI Machine Tool will focus on providing solutions relating to additive manufacturing, including provision of related expertise, to accelerate early adaptation to production parts.
Going forward, MHI Machine Tool will develop its metal printing services structure spanning from small-scale high-precision to ultra-large-scale items, enabling the Company to respond to a broad wide-range of prototype production needs and contract production. In these ways, MHI Machine Tool will encourage manufacturers to expand into manufacturing parts using metal 3D printers and contribute to the industrial supply chain as a whole.
(1) Directed Energy Deposition (DED) is an additive manufacturing (AM) process in which focused thermal energy is utilized to continuously feed metal powder materials by nozzle to laser fusing points, with pinpoint precision. (2) Binder jetting is an additive manufacturing process in which a binder is selectively sprayed by nozzle onto a thin layer of metal powder, causing solidification. With metals, heat treatment (binder removal and sintering) is then carried out to achieve the final product.
Mitsubishi Heavy Industries Machine Tool Co., Ltd., a part of Mitsubishi Heavy Industries (MHI) Group, announces June 2021 launch of the new GE15HS and GE25HS models of hobbing machines. Emphasizing high precision and efficiency, the new machines focus on electric and hybrid cars amid the global trend toward decarbonization. The new machines produce high-precision gears required in these new vehicles. These new machine models are a significantly improved addition to the GE Series of hobbing machines, which has shipped more than 2,800 units since its launch in 2004.
The GE15HS model is for gears with a maximum diameter of 150mm, widely used in automobiles and motorcycles. The high-speed, high-torque direct-drive motor(1) for the main cutting spindleprovides a maximum spindle speed of 6,000 min-1(2), three times faster than previous models. The high efficiency work table spindle holding the work piece uses a special table that provides high rigidity and high-speed rotation to handle the necessary thrust load(3) for high efficiency machining. Further, processing with the use of Mitsubishi super-hard cutting tools yields a surface roughness of less than Ra0.4(4), on a par with gear grinding. The GE15HS provides process efficiency, eliminating the finishing process of shaving prior to heat treatment, improving productivity and reducing processing cost.
The GE25HS model for large-diameter gears up to 250mm in diameter, such as automobile differential gears. With its high-efficiency processing, this model utilizes a high-speed, high-power spindle eliminating the effects of temperatures variation during production. The high rigidity table has the backlash eliminator incorporated as standard equipment. In addition, the motor torque and maximum spindle rotation speed of the main spindle have been increased 1.5 times from previous models, providing a 42% reduction in processing time(5). Used in combination with MHI Machine Tool’s new materials and coatings for cutting tools, the GE25HS model provide stable mass production with a cutting speed of more than 400m/min.
Demand for mass production of high-precision gears is continuing to rise with the shift to electrification of vehicles. With the need for improvements in NVH and fuel efficiency, and the move toward low-cost manufacturing. MHI Machine Tool, with expertise in both gear machine tools and cutting tools, offers a full lineup of gear production machines, including these two new models. By delivering precision cutting tools and processing solutions to achieve high-precision, high-efficiency processing, MHI Machine Tool provides comprehensive support for manufacturing in a wide variety of industries.
(1) Direct-drive mechanism motors utilize the torque coming from a motor without passing through a gear box or other mechanism in order to control driving loss due to friction and reduce wear on parts. (2) The “min-1” notation is a unit expressing the number of turns in one minute, synonymous with “revolutions/rotations per minute” (rpm). (3) Thrust load is the force applied to the shaft in a horizontal (parallel) direction (the axial direction of the rotor). (4) In-house machining result with GE15S (Workpiece data: Module 1.6mm; No. of teeth 19; Torsion angle: 24degrees; Tooth width: 24mm) (5) In-house machining result with GE25A-S (Workpiece data: Module 3mm; No. of teeth 54; Torsion angle: 30degrees; Tooth width: 40mm)
Mitsubishi Heavy Industries Machine Tool Co., Ltd., a Shiga-based part of Mitsubishi Heavy Industries, Ltd. (MHI) Group, has newly developed the “SE25FR Plus,” a gear shaping machine dedicated to making high-precision small-module(1) gears used in robots. The company has simultaneously developed a small-module cutting tool specifically for the new gear shaping machine. Full-fledged marketing of both new items will commence in March. By providing this dual support in high-precision gear cutting machines and cutting tools from a single source, MHI Machine Tool looks to respond to the need for reduction gears of increasingly higher precision in the expanding global robot market.
MHI Machine Tool launched its “FR Series”(2) of high-precision gear cutting machines in August 2020. The new SE25FR Plus is a high-end model developed especially for shaping strain wave gears(3), which require high precision. Outstanding rotation precision has been achieved through the adoption of ultra-high-precision bearings and direct-drive motors(4) in the two core components: the work table and the cutter head. This provides gear cutting precision of ISO class 3, enabling cutting precision higher than the model SE25FR, which is of ISO class 6.
The small-module cutting tool to be launched together with the SE25FR Plus features a newly developed dedicated tool material and a special coating, “MightyShield micro,” for micromachining. The tool material incorporates carbide particles offering improved toughness and wear resistance, while the new coating produces a uniform thin film below 2 micrometers (μm) thick that has no impact on tool shape error. The result is outstanding shaping even with difficult-to-cut materials, and the ability to achieve gear shapes down to the submicron level. Furthermore, MHI Machine Tool provides one-stop support in gear cutting machines and cutting tools, from the prototype development stage through mass production.
MHI Machine Tool is Japan’s only manufacturer producing both gear cutting machines and cutting tools. Moreover, the company possesses comprehensive proposal capability – encompassing not only its high-precision gear cutting machines but also all aspects relating to gear cutting, including cutting knowhow and automated systems. Going forward, as a leading producer of gear cutting machines to support not only the manufacturing industry but also the market for robots, which are increasingly adopted in the healthcare and service industries, MHI Machine Tool will continue to lead the way in “monozukuri”: the traditional Japanese concept of craftsmanship(5).
(1) Module (m) is a unit representing the size of a gear tooth. It is derived by dividing the diameter (mm) of the pitch circle by the number of teeth.
(2) The name “FR Series” derives from “Fine Pitch used Reducer for Robot.” Its development was undertaken in response to market expansion for industrial and life-support robots in recent years, which led to a sharp rise in demand for the high-precision small-module gears inside the precision reduction gears used in robot joints.
(3) Strain wave gears are mechanical devices that utilize the variance between elliptical and circular movements to reduce and output dynamic rotation speed.
(4) Direct-drive motors drive their target utilizing torque from the motor directly, without passing through a gear box or other intermediary mechanism; this enables suppression of wear on parts and driving loss due to friction, etc.
(5) Business in machine tools currently performed by MHI Group, including MHI Machine Tool, is scheduled to be transferred to Nidec Corporation and Nidec Group in May of this year.
