Date Published:Sep. 11. 2017 Date Updated:Jan. 19. 2024

What are clamp levers? Here we explain the characteristics and usage methods that help streamline screw tightening!

➡To [Description of Mechanical Components for Engineers]

What are clamp levers?

Clamp levers are mechanical components which allow efficient tightening and loosening of screws by turning the lever without the use of tools. Their best feature is the ability to work in tight spaces: just pull up the lever to release the threaded serration engagement (This will stop the screw from turning even if the lever is rotated).

Clamp Lever Structure

① Since the lever and threaded serration are normally engaged, turning the lever causes the screw to rotate simultaneously.
② Pulling up the lever releases the threaded serration engagement (the screw will stop turning when the lever is rotated).
③ Releasing the lever allows it to return automatically to lever and threaded serration engagement position due to the built-in spring force.




Only takes a minute to understand! How to Use Clamp Levers.

Using the features of the clamp lever ・・・

Screws can be tightened in places where the lever cannot rotate 360°.

After screw tightening, the lever position can be moved aside to keep it out of the way.

Solve your problems with clamp levers!

NBK clamp levers resolve customer issues.
Find examples introduced here.

・Frequent work with bolts takes time and causes trouble
・With space limitations, tools don't reach the work location and workability is poor
・Work locations for fixing need to be made clear at a glance

Frequent work with screws and bolts takes time and causes trouble

Higher work efficiency without tools

The use of clamp levers increases work efficiency, since tools such as wrenches and spanners used on screws are no longer required.
Clamp levers are efficient in places where screws are frequently handled, such as equipment changeover.

Space-saving for equipment

Space-saving for equipment

With a smaller rotating radius than normal tools, screw operation space can be reduced.
The NBK miniature clamp lever series, with an even smaller rotating radius, provides optimum space-saving for equipment.
>>Clamp Lever - Miniature Type Standard List
>>Clamp Lever - Miniature Type Flat Type List

Work locations for fixing need to be made clear at a glance

Easily standardize work

NBK clamp levers are available in a wide variety of colors.
This contributes to work standardization by drawing attention to the area of operation, clarifying operation procedures with different colors, and so on.

Examples of clamp lever applications

Application Examples

Shaft position adjustment

Workpiece fixing

Example Use Cases

Printing machinery

Application: Alignment adjustment for printing position
Product name:LDME, etc.

Food/packaging machinery

Application: Keeping equipment clean, helping prevent dust and debris from gathering
Product name:LDMS-AS, etc.

Types and Features of Clamp Levers

An abundant lineup is available from standard to unique products.
NBK will provide the clamp levers that meet your particular requirements.

Material Types

Lever materials include zinc die-cast, stainless steel, and plastic; materials for the threaded part include steel and stainless steel.

Material Types and Features

Material Types and Features Characteristics
Zinc Die Cast High Strength
Stainless Steel High Corrosion Resistant
Plastic Low Cost

Thread Part Material Characteristics
Steel High Strength
Low Cost
Stainless Steel High Corrosion Resistant

Screw Types

The two basic screw types are male and female.

Rotating Radius Types

The two types of rotating radiuses are "Standard" and "Compact".
The rotating radius for the "Standard" type varies, depending on the screw size, over a range from 45 mm to 108 mm.
The rotating radius for the "Compact" type is 30 mm for all sizes.

Function Types

Along with standard clamp levers, NBK also offers clamp levers with unique functions as an option.

With Push Button

The push button allows easy application of force when pulling up the lever, making operation easier.
The push button shape has no holes, helping prevent the accumulation of dust and dirt.

Clamp Lever with Built-in Washer

Clamp lever with washer built-in. When assembling to equipment, washer assembly is not required, keeping washers from falling out. Three types of washers are now available as standard. Select according to the usage application.

【Integrated Spring Washer Type】
Washer assembly is not required, preventing washers from falling out. Remove the plain washer to replace the spring washer with a different washer component.


【Integrated Plain Washer Type】
For reduction of seating surface pressure in materials with low limit surface pressure, such as resin and aluminum parts. Also ideal for ensuring seating surfaces when tightening slotted holes, etc.

【Integrated Flat Washer Type for Slotted Holes】

The pointer engraved on the top surface enables easy position confirmation when tightening slotted holes. The projection on the washer surface prevents the washer from rotating.

Metal Detectable

Clamp lever with metal powder admixed into the lever part resin, enabling detection with a metal detector.
For industries such as food manufacturing where contamination must be strictly prevented.

Plastic Clamp Levers-Metal Detectable
LEMS-MD(Male Screws)
LEFS-MD(Female Screws)

Universal Design

This clamp lever design incorporates the 7 principles of Universal Design.
>>About Universal Design

Lineup by Features

clamplever Lineup by Features

Product Finder

Our convenient "Product Finder" enables rapid searching for your desired products.

Additional Service

To make NBK products compatible with a wider range of applications, various additional standard modifications are available.
Orders of one piece or more can be processed for quick delivery.

Laser Engraving

Various marks and letters are laser-engraved on Clamp Levers. This is a service to make the NBK products even easier to use in terms of functionality by engraving marks such as OPEN, CLOSE, and arrows.

Click here for details >

Length Adjustment

Screws can be cut to your desired length in 1mm increments.

Click here for details >

Screw Combination

Levers/clamp levers’ female screws are bonded with screws by anaerobic adhesive agent and fixed with pins.

Click here for details >

Cleanroom Services

We can wash and pack your products in a cleanroom. This is suggested for products used in FPD production devices, semiconductor manufacturing devices, medical equipment, food and beverage machinery and even products that will be used in cleanrooms.

Click here for details >

Special Products

Come to us for production of non-standard clamp levers as well, including lever part color changes and special shapes.

Find related articles on Clamp Levers here

Description of Mechanical Components for Engineers

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