Interview【Sodick User Report】 Sumida-ku, Tokyo
Yoshizumi Press Co., Ltd.

Drawing, bending and punching of thin material
High cost performance can only be provided by various press technologies

Sodick 4 axis linear motor drive wire-cut EDM
Over 10 years in service since first introduced for use in mold processing Stable, high precision machining over an extended period of time.

In pursuit of a diverse range of technology

The promise of reduced costs represents a major reason why the manufacturing industry is shifting overseas and to regional areas.
With this in mind, the high cost of land in Tokyo makes retaining a manufacturing base in Tokyo harder as each year passes. The reality is, the number of manufacturing firms (with four or more employees) operating in the Tokyo metropolitan area has been cut in half over the last 10 years, to around 10,000 companies. Leveraging some form of unique advantage, and providing high added value, are absolutely essential to keep manufacturing in the Tokyo metropolitan area.

Located in Sumida-ku, Tokyo, Yoshizumi Press is involved in the entire manufacturing process, from molding to progressive die press processing, continuing to deliver parts that offer high added value. The broad range of parts the company deals in is another standout feature, and the company’s work can be found in anything from smartphones, to stationery and automotive parts.
Yoshizumi Press was founded in 1950. The company started from humble beginnings, machining latches for handbags using a single foot press machine. In 1993 they began making their own molds, and expanded the scope of the business, producing lithium ion batteries, and a wide range of parts for smartphones, automotives, and the like.

The catalyst that prompted the company to expand its range lay in “the difficulties faced specializing in a single part” (Managing Director Ken Yoshizumi), and the broad range of press-related know-how, namely in terms of drawing, bending and punching techniques, the company has accumulated from this diverse scope of experience has manifested into one of the company’s defining strengths.

The colorful doorway, which opens to views of the Tokyo Skytree looming ahead, gives the impression of a place brimming with manufacturing ideas.

Enriching ideas, on the search for the next generation in technology

The company eagerly leaps at the opportunity to explore new fields, not only for its own products, but for its main business line of parts processing as well. One target it has set its eyes on for the future is batteries for industrial drones. The company sees “Increased demand for drones in the future. While China maintains a large market share, we see a range of avenues in which our technology can be applied due to the need for high levels of precision in built-in batteries”.

Although the company is constantly on the lookout for new fields to explore, discovering fields and latent needs set to grow in the future is no mean feat. Managing Director Yoshizumi reflects on the unique ways in which the company seeks out potential future opportunities, stating “We regularly draw on web sites like the New Energy and Industrial Technology Development Organization (NEDO) as a basis for considerations as to what areas will potentially see growth 10 years from now”.

Looking ahead, the company is set to pursue a Sumida-ku brand of high value added manufacturing born out of a “Desire to produce technologies that cannot be mimicked elsewhere” , while continuing to develop the company’s technical capabilities and maintaining a keen grasp on future growth markets.

Gage part for seal impression (left)
The automotive camera shield case (center & right) is of extremely high-quality, maintaining a precise outline
Source: Yoshizumi Press Precision Parts

Example 1
Internal smartphone connector components

The company’s drawing technology is what led to the successful development of connector components that had previously been unachievable by other companies.
“This development was out of reach for connector manufacturers that did not implement a drawing phase. Discussions with users is what led us to draw the conclusion that drawing technologies could be used to reach a solution” (Managing Director Yoshizumi). Looking ahead , “We see drawing technologies as becoming all the more important with the need for connectors to retain a high level of sealing performance”.

Example 2
Internal fountain pen cartridge components (cutting -> press)

These cartridges contain a washer. These components hold multiple balls used to prevent ink clots.
We succeeded in shifting from the conventional cutting process used for these parts, to pressing these parts.

Example 3
Proposing optimal shapes based on a comprehensive understanding of pre- and post-processes

Have you ever gotten attached to a pen straight away, to the point where that is all you will use? You like the design, and the pen offers great durability. You grow fonder of it with everyday use. The company approached a customer proposing that shape changes be made to a part used in a piece of stationery to allow for better control after molding, a proposal that was accepted.
“While the price of each is reasonable, each component is a work of art. This really is a product worth making” , espouses Managing Director Yoshizumi. Previously, these parts often became entangled in the process after pressing. The addition of this barb resolved issues with in-process defects and greatly improved productivity.
The ability to oversee the entire manufacturing process, and make proposals that take a wide range of considerations into account, has led to numerous instances of yield improvements.

Example 4
APY brand producing finely-detailed, beautiful finishes for strong metals

A hook you can hang and peel off. This hook uses a special suction sheet called a Pita sheet.
It can be attached to glass, stainless steel, metal coated surfaces (fridges, etc.) and other smooth surfaces multiple times. A wide range of color variations are also available.

A mini clip that can be used in a wide range of scenarios in the office and the home, from clipping documents together, to displaying photos.

“We have wanted to try our hand at making our own products for a while now. Lining up our products in a shop display is a great source of motivation for our employees” , states Managing Director Yoshizumi.

Source: Yoshizumi Press website
Source: Yoshizumi Press catalog LINE HOOK / DOT HOOK / MINI CLIP

Managing Director Ken Yoshizumi Managing Director
Ken Yoshizumi
Yoshizumi Press Co., Ltd.
Iwao Yoshizumi, President
Head factory:4-28-2 Tachibana, Sumida-ku, 131-0043 Tokyo
Business Activity
Design and manufacture of thin progressive die press parts in the 0.05 to 2.3 mm range and molds
Production Equipment
[Sodick Products] Wire-cut EDMs 5
[Others] Servo press devices