KSS

What KSS does

KSS Co., Ltd. is a Japanese privately held manufacturer of miniature ball screws and actuators, founded in 1960 and headquartered in Ota-ku, Tokyo, with a primary production facility in Ojiya City, Niigata Prefecture, and a regional sales office in Shanghai, China. The company specializes in miniature ball screws and actuators with shaft diameters of 16mm or less, and developed the world's smallest commercial ball screw (1.8mm shaft diameter, 0.5mm lead) in November 2001. Core products include precision and rolled ball screws, precision lead screws, lead screws with plastic nuts, linear actuators in multiple form factors (MoBo external direct-drive series, captive/non-captive electric cylinders, miniature single-axis actuators), the VZθ multi-functional actuator combining linear, rotary, and vacuum functions, ball screw with ball spline (BSSP) combined products, and electric grippers.

The company's technology platform rests on several proprietary innovations: the MoBo (Direct Motor Drive Ball Screw) architecture, which mounts the stepping motor directly onto the ball screw shaft to eliminate couplings and is protected by US Patent No. 6791220 and Korea Patent No. 10-2002-0027825; the BSSP architecture co-developed with HEPHAIST Seiko; and proprietary grease formulations (MSG No.1/No.2, MCG No.1) for miniature ball screw lubrication. KSS holds three ISO certifications: ISO 9001:2015 (since 1999, renewed March 2025), ISO 14001:2015 (since 2005, renewed March 2026), and ISO 13485:2016 for medical devices (since 2020, renewed January 2026).

KSS generates revenue through one-time sales of standard and customized products to enterprise OEMs, with no public revenue disclosure. Distribution is conducted through direct sales from Tokyo and Ojiya offices, a Shanghai regional office, and a network of international sales agents. End-customers span semiconductor and LCD production equipment manufacturers (the primary segment), medical device and surgical robot manufacturers, robotics, machine tools, inspection apparatus, food processing, injection molding, aerospace, and automotive industries. The company is family-controlled, led by the Ota family, with Takahisa Ota as President since March 2022, and is not venture-backed, PE-owned, or publicly listed.

Name

KSS

Legal name

KSS Co., Ltd.

Website

https://kssballscrew.com

Company type

Private

Founded year

1960

Operating status

Operating

Headcount range

51–100 employees

Short description

KSS Co., Ltd. is a Japanese manufacturer of miniature ball screws and actuators (16mm or less shaft diameter), serving semiconductor, LCD, medical device, robotics, and industrial automation OEMs through direct sales and a global agent network.

Ownership category

akta.pro rank

Product category

Precision Motion Components

NAICS

Turned Product and Screw, Nut, and Bolt Manufacturing (33272), Speed Changer, Industrial High-Speed Drive, and Gear Manufacturing (333612), Fluid Power Cylinder and Actuator Manufacturing (333995)

SIC

Screw Machine Products (3451), Ball & Roller Bearings (3562), Bolts, Nuts, Screws, Rivets & Washers (3452)

akta.pro primary industry

Linear Motion & Mechanical Power Transmission (Ball/roller screws, linear guides, bearings, couplings) (IMAHAGAM)

akta.pro secondary industries

Actuators & Motion Devices (Linear, Rotary, Electric Actuators for Motion Control) (IMAHAGAG), Linear Motion & Actuation (Linear Motors, Electric Cylinders, Actuators) (IMAGACAG), Motion Control Electronics & Controls (Controllers, Drivers, Feedback Interfaces) (IMAHAGAJ)

Keywords

• Miniature ball screws
• Linear actuators
• Precision motion components
• Direct motor drive ball screws
• Electric grippers

Headquarters

HQ city

Tokyo

HQ country

Japan

HQ region

Asia

Offices4 records

Markets served

GTM type

B2B

Offering type

Hardware or Manufacturing

Cost components

Personnel, Supply Chain, Technology or R&D, Operations, Marketing or Sales, Infrastructure

Revenue model

1. Miniature Ball Screws and Actuators Sales: Design, develop, manufacture and sell Miniature Ball Screws, Miniature Actuators and related products, with focus on miniature size (16mm or less shaft diameter). Products include Precision Ball Screws, Rolled Ball Screws, Precision Lead Screws, Lead Screws with Plastic Nuts, Linear Actuators, and specialized motion control components sold to industrial customers.
2. Support Units and Accessories: Sale of complementary products including Compact Support Units for Miniature Ball Screws (Pillow type and Flange type), KSS Original Grease formulations, and Stepping Motor Drivers.
3. Customized/Special Requirement Products: Custom-designed products for special environments, with special profiles or coatings such as Plastic Ball Screws, Black Chrome coating, Ball Screws with trunnion, X-Y stages, Pen type Actuators, and Small sized stages.

Pricing tiers

Go-to-market motion2 records

Distribution channels4 records

Marketing channels7 records

Core offering

KSS designs, develops, manufactures, and sells miniature Ball Screws (16mm or less shaft diameter) and related Actuators for industrial precision motion applications. The product portfolio includes Precision Ball Screws, Rolled Ball Screws, Precision Lead Screws, Linear Actuators (external, captive, non-captive), Miniature/Single Axis Actuators, the VZθ multi-functional Actuator, Electric Grippers, and Ball Screw with Ball Spline (BSSP) products. Supporting accessories include KSS Original Greases, Compact Support Units, and Stepping Motor Drivers.

Product overview

KSS is a general manufacturer of Ball Screws and Actuators, specializing in miniature sizes (16mm or less shaft diameter). The product portfolio centers on precision and rolled ball screws as the core technology, with related linear motion products including: Precision Ball Screws and Rolled Ball Screws (main product lines); Precision Lead Screws and Lead Screws with Plastic Nuts (alternative linear motion solutions); Linear Actuators in multiple form factors (External/MoBo series, Miniature/Single Axis actuators, Captive/Non-Captive electric cylinders, and VZθ multi-functional actuators combining linear, rotary, and vacuum functions); Ball Screw with Ball Spline (BSSP) multi-purpose products enabling combined linear and rotational motion; and Electric Grippers. Supporting accessories include original greases, compact support units, and stepping motor drivers. Custom/special requirement products for special environments are also offered.

Differentiator

Problem solved

Functional benefit

Brands

• MoBo: Direct Motor Drive Ball Screw product line. MoBo technology mounts the motor directly onto the ball screw shaft, eliminating coupling for compact design.
• VZθ Actuator
• Flex Actuator (FA Series)
• BSSP

Products and services

• Precision Ball Screws Miniature ball screws with high accuracy achieved through grinding process. Shaft diameter as small as 1.8mm, the world's smallest class. For industrial OEM customers in precision manufacturing equipment.
• Rolled Ball Screws Ball screws with rolling-formed screw groove providing appropriate accuracy at reasonable price. Includes NSR, SR/SSR, SRT/SSRT, and PSR/PSRT series. For industrial OEM customers.
• Precision Lead Screws Lead screws supporting metric fine thread, metric coarse thread, trapezoidal thread, unified screw thread, ACME screw thread, and custom pitches. Down to 0.1mm finest pitch. For industrial precision applications.
• Lead Screws with Plastic Nuts Economical lead screws with stainless steel shaft and plastic nut. Includes MRH-A, MRH-B, MRH-BP2, and R-MSS series with lubricating agent incorporated. For special environments and cost-sensitive applications.
• Linear Actuator External (MoBo Series) External linear actuators combining stepping motor and ball screw/lead screw without coupling. Direct motor drive design minimizes lost motion. Includes MB, TMB, 2TMB, SiMB, and ReMB series. Patented MoBo technology.
• Miniature Actuators / Single Axis Actuators Super compact actuators utilizing miniature ball screw technology. Available in cylinder type and slider type. Includes FA Series (Flex Actuator) and MoBo Actuator (MA Series). For industrial automation and robotic applications.
• VZθ Actuator Multi-functional actuator combining Linear (Z), Rotary (θ), and Vacuum (V) functions in one unit. Uses Ball Screw with Ball Spline (BSSP) technology. Available in Direct Drive, Hybrid, and Belt Drive types. For automation and robotic applications.
• Linear Actuator Captive and Non-Captive (Electric Cylinder) Cylinder type actuators with motor built into ball screw or lead screw. AR series includes anti-rotating device using Ball Spline Nut; CL series requires external anti-rotating setup. For positioning and lifting applications.
• Electric Gripper Lightweight and compact electric gripper using ball screw technology. Features high accuracy gripping force, positioning, and speed control. Includes CGS series (Compact Electric Gripper) and RG series (Gripper with Rotary Module). For automation and robotics.
• Ball Screw with Ball Spline (BSSP) Multi-purpose product combining ball screw and ball spline on same shaft, enabling both linear and rotational movement. Features vacuum/blow function through bore hollow. Available in overlap and separated types. Co-developed with HEPHAIST Seiko.
• KSS Original Grease Proprietary lubricants developed specifically for miniature ball screws. MSG No.1 for positioning, MSG No.2 for general use, MCG No.1 for clean room environment. Supporting accessory for KSS ball screws and actuators.
• Ball Screw Support Units Compact support units for miniature ball screws, available in pillow type and flange type for both fixed-side and supported-side mounting. Pre-load controlled angular contact bearings installed. Supporting accessory.
• Stepping Motor Drivers Compatible drivers for direct motor drive ball screws and actuators. Includes KR-A5CC (5-phase), KR-A55MC (5-phase micro-step), KR-A535M, SD4015B3, and SD4030B3 (2-phase micro-step). Supporting accessory for actuator products.
• Special Requirements / Custom Products Custom products for special environments including plastic ball screws, black chrome coating (BCr), ball screws with trunnion, X-Y stages, pen type actuators, and small sized stages. Tailored to customer specifications.
• Flexible Link (FX Series) Compact sub-unit combining Ball Screw and Fixed side Support Unit. KSS proprietary coupling technology minimizes connecting dimensions and provides flexibility in ball screw and motor combinations.
• Precision Ball Screws for ISO(DIN) Standard Ball screws with Nut outer diameter conforming to ISO standard (ISO 3408-2 series1 / DIN 69051-5). Reinforced recirculating device and optimized Ball track of circulation for improved rotational performance and durability.
• Rolled Ball Screws for ISO(DIN) Standard Rolled ball screws conforming to ISO/DIN standards with optimized ball circulation. For industrial OEM customers requiring standard-compliant components.

Quantifiable outcome

• World's smallest Ball Screw with 1.8mm shaft diameter and 0.5mm lead developed in November 2001

Named customers10 records

Segments5 records

Ideal customer profiles3 records

Technology focussed No

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Integration2 records

Feature7 records

Partnerships

Four partnerships are on record, tiered core and minor.

• HEPHAIST Seiko Co., Ltd.coreStrategic or Co-development Partner · 1 April 2010HEPHAIST collaborated with KSS to develop Ball Screw with Ball Spline (BSSP), combining KSS's Ball Screw technology with HEPHAIST's Ball Spline expertise. This hybrid product enables both linear and rotational movement in one compact unit, with air suction capability through bore hollow. The product is focused on hybrid, compact, and lightweight design.
• NTN Engineering Plastics CorporationcoreStrategic or Co-development Partner · 1 March 1995Jointly developed 'Bearee' resin lead screws with NTN Engineering Plastics Corporation in March 1995. This partnership enabled KSS to offer plastic ball screws and lead screws with plastic nuts for special environments where steel cannot be adapted.
• Japan Machine Accessory Association (JMAA)minorOthersKSS is a member of the Japan Machine Accessory Association, participating in industry networking and standards development activities.
• The Japan Society for Precision EngineeringminorOthersKSS participates in the Technical Committee of Ultra Precision Positioning under The Japan Society for Precision Engineering. Joined the technical committee in January 1995.

Scale indicators6 records

Recent moves12 records

Expansion highlights6 records

Direct peers

• NSK Ltd. Major Japanese ball screw and bearing manufacturer. Directly competes across precision and miniature ball screw sizes, with much larger scale and established OEM relationships in machine tool and semiconductor equipment.
• Hiwin Technologies Corp. Taiwanese manufacturer of ball screws, linear guides, and actuators. Competes head-to-head with KSS in miniature and precision ball screws for semiconductor, medical, and automation applications globally.
• THK Co., Ltd. Japanese global leader in linear motion (LM Guides, ball screws, actuators). Directly competes with KSS in miniature and standard ball screws, and offers broader product portfolio with stronger global service network.
• Nippon Bearing (NB) Co., Ltd. Japanese manufacturer specializing in miniature bearings and linear motion components. Highly comparable niche positioning and customer base to KSS, focused on compact precision motion for electronics and medical equipment.

Broad incumbents

• SKF Group: Swedish bearings and linear motion giant. Offers ball screws and actuators within a far broader rotating equipment portfolio, competing for the same industrial automation and OEM customers as KSS.
• SMC Corporation: Japanese global leader in pneumatics and industrial automation components. Competes with KSS in factory automation actuators and motion subsystems, though primarily via pneumatic rather than mechanical ball screw technologies.
• Bosch Rexroth: German leader in factory automation, motion control, and linear technology. Competes with KSS in ball screws and linear actuators as part of a comprehensive systems offering to industrial OEMs.
• Schaeffler Group (INA): German broad-line motion and bearing supplier (INA/FAG/LuK). Overlaps with KSS through precision ball screws and linear actuators as part of a much larger industrial portfolio serving similar automation customers.

Emerging players

• Oriental Motor Co., Ltd. Japanese specialist in stepping motors, servo motors, and integrated actuators. Closely comparable in targeting miniaturized motion subsystems and overlapping with KSS's actuator and motor-driver offerings.
• PBC Linear: US-based specialist in linear motion components including miniature ball screws and actuators. Comparable in product scope and target customers (medical, semiconductor, automation) though smaller in scale than KSS.

Market position

Strengths5 records

Weaknesses5 records

Competitive moat6 records

Key risks6 records

Key highlights7 records

Customer concentration

• Xx.com/ksscoltd_japan
• YouTubeyoutube.com/user/KSSofficial?feature=watch
• Facebookfacebook.com/pages/%E3%82%B1%E3%83%BC%E3%82%A8%E3%82%B9%E3%82%A8%E3%82%B9%E6%A0%AA%E5%BC%8F%E4%BC%9A%E7%A4%BE-KSS-CoLtd/137258389696390
• LinkedInlinkedin.com/company/kss-co--ltd-?trk=company_logo

Compliance4 records

Revenue estimate

Valuation estimate

Number of profiles

Profiles8 records

Funding overview

Funding rounds

Investors

Funding detail is available on the Subscription and Enterprise plan.Contact sales →

M&A

Investments

M&A and investment is available on the Subscription and Enterprise plan.Contact sales →

Frequently asked questions about KSS