Power-Lock (Locking Device )

Power-Locks are friction type locking device for easy, strong and secure non-backlash connections of shafts and hubs.

As the locking is done by frictional force using the wedge effect, the shaft and hub can be locked simply by tightening the bolt, without the need for fixing with a key or set screw, and removal is easy.

The line-up of materials also includes steel, stainless steel and coated versions, which can be used in a variety of situations.

Basic construction

・Double taper type (AS Series )

Product photo

Structural drawing

・Single taper type (KE Series )

Product photo

Structural drawing

Locking principle

・Double taper type

Double taper type

[Click to enlarge ]

The inner diameter of taper ring A and taper ring B has a tapered shape, and is in contact with the taper of the inner diameter of the outer race and inner race.

By tightening the locking bolts, the taper rings A / B approach each other and generate contact pressures P and P' on the inner race. The contact pressure of P and P' generates a frictional force that completely locks the hub and shaft.

・Single taper type

Single taper type

[Click to enlarge ]

The inner diameter of the outer ring and the outer diameter of the inner ring are tapered. By tightening the locking bolt, the outer ring moves while sliding on the tapered surface and the inner surface of the hub.

At this time, radial forces P and P' that press the shaft and the inner surface of the hub against each other are generated by the wedge effect. The force of P and P' generates a frictional force that strongly locks the hub and shaft.

Features

  • ・The processing cost of the shaft and hub is low. (No keyway processing required. )
  • ・Ideal for high-precision position control with no backlash.
  • ・No worry about thiner or seizure shaft. (No worry about wear )
  • ・Easy phase alignment and advantageous for positioning cams and gears.
  • ・It is easy to assemble and disassemble, and does not require skill for work like shrink fitting.
  • ・No need for retaining due to thrust load.
  • ・There is no decrease in shaft strength due to the keyway.
  • ・Rotational balance is better than key fastening.

Notes

・Power-Lock is available with or without self-centering function depending on the series.

See more about the self-centering function

What is the self-centering function?

The self-centering function refers to the function to suppress the runout of the hub when the shaft and hub are tightened.

In other words, it is a function of how much the axis can be brought to the center of the hub.

POWER-LOCK has a series with or without a self-centering function. For a series without a self-centering function, the hub must be provided with a guide part (a part where the shaft and hub come into direct contact).

Practical centering accuracy can be obtained if the guide length is expected to be half the shaft diameter.

・Hub moves during assembly without flange.

See the detailed explanation about hub movement during assembly

What is the hub movement during assembly?
What is the hub movement during assembly?

※Images of RE-SS series with and without flange (snap ring) are shown for reference.

In the series with a flange, the flange becomes a stopper when the locking bolt is tightened. Even if the hub comes close to the front together with the outer ring, it is stopped, and it slides on the outer ring and the inner surface of the hub.

However, because there is no stopper in straight mounting without a flange (figure at the top right), the hub will come close to the front together with the outer ring when the locking bolt is tightened. (However, as there is no loss due to sliding, the transmission torque increases.)

For applications where it is difficult for the hub to move, select a type that does not move the hub.

Product Lineup for Power-Lock

Standard package

You can select the most suitable Power-Lock from a wide range of lineups.

Applicable shaft diameters range from a small diameter of Φ5 to a maximum of Φ500, and each series meets a wide range of needs, from highly compatible general-purpose type to types for small-diameter hubs, large-capacity, external locking, nut-tightening and types for a wide range of shaft tolerances.

KE Series

Model No.  PL□□X□□KE

View product details

With a lineup from small diameter shafts, it can be used for a wide range of shaft tolerances.

  • ・Designed to suit a wide range of shaft tolerances. Standard models can accommodate plus shaft tolerances of servomotors, etc.
  • ・Smaller inner/outer diameter ratio, compatible with small-diameter hubs. Compact design is possible.
  • ・Suitable for locking small stepping motors and servo motor output shafts with a range of small diameter sizes.
  • ・Simple structure with a small number of parts and excellent cost performance.
  • ・In addition to stainless steel series and electroless nickel plating series, Low Contact Pressure series are also available.
  • ※With its self-centering function, eliminates the hassle of machining on hubs for guide portions.
  • ※No hub movement during assembling.
Taper specification

Single taper

Centering function

Provided

Applicable shaft diameter

Φ5~Φ100

Torque range

7.5~9900N・m

Applicable tolerance

Shaft :h6,h7,js6,js7,k6,m6
Hub hole :H8

Applicable surface roughness

Ra1.6

AS Series

Model No.  PL□□X□□AS

View product details

It is the most popular global standard model.

  • ・Many manufacturers are available both domestically and abroad, and this series is highly compatible.
  • ・Fewer bolts compared to other company’s products by employing high-strength locking bolts, allowing reduced time and manpower for installation.
  • ・The large taper angle makes it easy to tighten and remove. The easiest to handle in the series.
  • ・It covers a wide range of shaft diameters from Φ19 to Φ500. Inch size is also available.
  • ・Stainless steel specifications and electroless nickel plating specifications are also available. Can be selected by applications.
  • ※It does not have a self-centering function, so it is necessary to provide a guide part on the hub.
  • ※No hub movement during assembling.
Taper specification

Double taper

Centering function

None

Applicable shaft diameter

Φ19~Φ500

Torque range

294~555000N・m

Applicable tolerance

Shaft :h8 Hub hole :H8

Applicable surface roughness

Ra1.6

AD-N Series

Model No.  PL□□X□□AD-N

View product details

High torque transmission capacity type

  • ・Capable of transmitting 1.5 to 3 times the AS Series rated torque capacity.
  • ・Designed with the same inner and outer diameters as the AS Series, you can use fewer units of the AD-N Series to replace AS Series units.
  • ・Packages finished with electroless nickel plating are also available. perfect for applications requiring very high capacity in clean room environments.
  • ・Only Tsubaki products are available from Φ19. Large capacity torque transmission for small diameter shafts should be left to.
  • ※Careful work is required for assembly and removal.
  • ※With its self-centering function, eliminates the hassle of machining on hubs for guide portions.
  • ※No hub movement during assembling.
Taper specification

Double taper

Centering function

Provided

Applicable shaft diameter

Φ19~Φ300

Torque range

382~429000N・m

Applicable tolerance

Shaft :h8 Hub hole :H8

Applicable surface roughness

Ra1.6

AE Series

Model No.  PL□□X□□AE

View product details

Type with flange and self-centering function that has the same inner and outer diameters as the AS series.

  • ・This Series has the same inner and outer diameters as AS Series, and is suitable when a centering guide part is not provided.
  • ・Simply constructed with only an inner and an outer ring and a few locking bolts.
  • ・Many manufacturers are available both domestically and abroad, and this series is highly compatible.
  • ※With its self-centering function, eliminates the hassle of machining on hubs for guide portions.
  • ※No hub movement during assembling.
  • ※In the case of step shaft installation, make sure the space between the hub and the steps is greater than 1 mm.
    If there is no space, it may be difficult to remove.
Taper specification

Single taper

Centering function

Provided

Applicable shaft diameter

Φ19~Φ150

Torque range

265~27000N・m

Applicable tolerance

Shaft :h8 Hub hole :H8

Applicable surface roughness

Ra1.6

TF Series

Model No.  PL□□X□□TF

View product details

Suitable for small hub applications with the small inner-to-outer diameter ratio.

  • ・Designed to fit small hub diameters with the smallest available inner-to-outer diameter ratio of our Power Lock series.
  • ・Minimum number of locking bolts used, enabling reduced installation time.
  • ・Many manufacturers are available both domestically and abroad, and this series is highly compatible.
  • ・Packages finished with electroless nickel plating are also available.
  • ・Constructed of the following four parts: inner and outer rings, a spacer and locking bolts.
  • ※With its self-centering function, eliminates the hassle of machining on hubs for guide portions.
  • ※No hub movement during assembling.
Taper specification

Single taper

Centering function

Provided

Applicable shaft diameter

Φ6~Φ90

Torque range

11~8820N・m

Applicable tolerance

Shaft :h8 Hub hole :H8

Applicable surface roughness

Ra1.6

EL Series

Model No.  PL□□X□□E

View product details

The simplest element type allows for optimal design.

  • ・You are free to select the tightening of bolts and number of EL Power Rocks to be installed, so various design configurations are available depending on the required locking force.
  • The complete ring shape design offers excellent dynamic balance.
  • ・Compact and lightweight. Requires a minimum of installation space.
  • ・Provides superior cost performance and fit for applications requiring many Power-Locks.
  • ・Many manufacturers are available both domestically and abroad, and this series is highly compatible.
  • ※The pressure flange, pressure sleeve, and locking bolt must be prepared by the customer.
  • ※Outering pressurize is basic. In this case, there is no hub movement during assembly.
  • ※It does not have a self-centering function, so it is necessary to provide a guide part on the hub.
Taper specification

Single taper

Centering function

None

Applicable shaft diameter

Φ10~Φ150

Torque range

6.9~10500N・m

Applicable tolerance

Shaft :
 Φ10~38 h6
 Φ40 or over h8
Hub hole :
 Φ10~38 H7
 Φ40 or over H8

Applicable surface roughness

Ra0.8

EF Series

Model No.  PL□□X□□EF

View product details

A pressure flange integrated type with the same inner and outer diameters as the EL series.

  • ・The EF Series, designed with the same inner and outer diameters as the EL Series, integrated pressure flange saves you the hassle of making a pressure flange.
  • ・The EF Series offers 2 to 3 times the rated torque capacity of the EL Series. You can use fewer units of the EF Series to replace EL Series unit.
  • ・Suitable for small hub applications with the small inner-to-outer diameter ratio.
  • ・Simply constructed with only an inner and an outer ring and a few locking bolts.
  • ・Tsubaki's original series, which are not available in any other company.
  • ※With its self-centering function, eliminates the hassle of machining on hubs for guide portions.
  • ※When assembling, the hub moves slightly toward the front in the axial direction. Please contact Tsubaki representatives for details.
Taper specification

Single taper

Centering function

Provided

Applicable shaft diameter

Φ10~Φ120

Torque range

39~12600N・m

Applicable tolerance

Shaft :h8 Hub hole :H8

Applicable surface roughness

Ra1.6

ML Series

Model No.  PL□□X□□M/MG

View product details

These units are quick to connect with a single nut.

  • ・Can be easily locked with a single nut. Installation time can be significantly reduced.
  • ・Surface plated, simple rust prevention, and special surface treated nuts do not require oil to be applied during assembly.
  • ・Only available in the series for mounting on hubs shorter than the POWER-LOCK width.
  • ・The locking torque can be changed in the range of 1/2 to 1.1 times the standard. Can be used according to the strength of the hub.
  • ※ML type for shaft diameters up to Φ32 and MG type for Φ34 and over, and appearance also differs.
  • ※With its self-centering function, eliminates the hassle of machining on hubs for guide portions.
  • ※When assembling, the hub moves slightly toward the back in the axial direction. Please contact Tsubaki representatives for details.
Taper specification

Single taper

Centering function

Provided

Applicable shaft diameter

Φ5~Φ75

Torque range

6.76~2000N・m

Applicable tolerance

Shaft :h8 Hub hole :H8

Applicable surface roughness

Ra1.6

SL Series

Model No.  PL□□X□□SL

View product details

External locking type to tightened from the outside of the hub.

  • ・Especially suitable for hollow shaft connections such as reducers.
  • ・It can be used where design limitations force the use of thin-walled hubs.
  • ・Coated with a special lubricant eliminating the necessity to apply oil and grease .
  • ・The larger the shaft diameter, the greater the torque can be transmitted.
  • ・Simple structure for easy mounting and removal.
  • ※No hub movement during assembling.
  • ※When used for a hollow shaft, the inner diameter of the hollow shaft must be considered at the time of selection.
Taper specification

Double taper

Centering function

No need due to external locking type.

Applicable hub outer diameter

Φ24~Φ300

Torque range

167~290000N・m

Applicable tolerance

Hub outer diameter :h7 Hub hole :H7

Applicable surface roughness

Ra1.6