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Full-Ball Type LM Guide Structural Member Rail Model JR

Since its LM rail has a sectional shape with high flexural rigidity, this LM Guide can be used as a structural member.

  • Self-adjusting capability
  • 4-way equal load
  • Structural member rail

Size : 25,35,45,55

Types

Highlight feature tags

  • Flange
  • Bolts mounted from above
  • Bolts mounted from below
Model JR-A
  • Flange
  • Bolts mounted from above

Basic load rating (kN): Basic dynamic load rating 27.6 to 121 / Basic static load rating 36.4 to 146
Size : 25,35,45,55

Model JR-B
  • Flange
  • Bolts mounted from below

Basic load rating (kN): Basic dynamic load rating 27.6 to 121 / Basic static load rating 36.4 to 146
Size : 25,35,45,55

Model JR-R
  • Bolts mounted from above

Basic load rating (kN): Basic dynamic load rating 27.6 to 121 / Basic static load rating 36.4 to 146
Size : 25,35,45,55

Features

Structure and Features

Balls roll in four rows of raceways precision-ground on an LM rail and an LM block, and endplates incorporated in the LM block allow the balls to circulate. Since retainer plates hold the balls, they do not fall off even if the LM rail is pulled out.
Model JR uses the same LM block as model HSR, which has a proven track record and is highly reliable. The LM rail has a sectional shape with high flexural rigidity, and therefore can be used as a structural member.
Unlike the conventional LM Guide type, whose LM rail was secured onto the base with bolts when installed, model JR’s LM rail is integrated with the mounting base, and the top of the LM rail has the same structure as LM Guide model HSR. The lower part of the LM rail has a hardness of 25HRC or less, making it easy to cut the rail and enabling the rail to be welded.
When welding the rail, we recommend using welding rods compliant with JIS D 5816. (suggested manufacturer and model number: Kobelco LB-52).

4-way Equal Load

Each row of balls is placed at a contact angle of 45° so that the rated loads applied to the LM block are uniform in the four directions (radial, reverse radial and lateral directions), enabling the LM Guide to be used in all orientations.

Can be Mounted Even Under Rough Conditions

Since the center of the cross-section of the LM rail is slightly thinner, even if the parallelism between two rails is not accurate the LM rail is capable of absorbing the error by bending inward or outward.

Sectional Shape with High Flexural Rigidity

Since the LM rail has a sectional shape with high flexural rigidity, it can also be used as a structural member. In addition, even when the LM rail is partially fastened or supported in cantilever, the distortion is minimal.

Second Moment of Inertia of the LM Rail


Geometrical moment
of inertia

I [×10 5 mm4 ]

Modulus of
section

Z [×10 4 mm3 ]

Height of
gravi-
tational
center

H[mm]

AboutX axis

AboutY axis

AboutX axis

AboutY axis

JR 25

1.90

0.51

0.69

0.21

19.5

JR 35

4.26

1.32

1.43

0.49

24.3

JR 45

12.1

3.66

3.31

1.04

33.1

JR 55

27.6

6.54

5.89

1.40

43.3

Detailed information for each model number

Dimensional drawing/Dimensional table

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Products Contents
LM Guide LM rail standard lengths and maximum length, tapped-hole type LM rail, frame for LM rail clamps, steel plate for LM rail clamps, etc.
Ball Screw Axial clearance, maximum manufacturing length of shaft, etc.
Actuator Movable part mass, etc.

Standard Length and Maximum Length of the LM Rail

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Member-Exclusive Content

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Benefit 1: Useful features

  • Easy product comparisonsHighlight feature
  • Save items for laterreview Favorites feature

Benefit 2: Exclusive content

Products Contents
LM Guide LM rail standard lengths and maximum length, tapped-hole type LM rail, frame for LM rail clamps, steel plate for LM rail clamps, etc.
Ball Screw Axial clearance, maximum manufacturing length of shaft, etc.
Actuator Movable part mass, etc.

Model JB frame for LM rail clamps

THK Online Services
Member-Exclusive Content

These contents can be accessed

after registering as a member.

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Benefit 1: Useful features

  • Easy product comparisonsHighlight feature
  • Save items for laterreview Favorites feature

Benefit 2: Exclusive content

Products Contents
LM Guide LM rail standard lengths and maximum length, tapped-hole type LM rail, frame for LM rail clamps, steel plate for LM rail clamps, etc.
Ball Screw Axial clearance, maximum manufacturing length of shaft, etc.
Actuator Movable part mass, etc.

Model JT steel plate for LM rail clamps

THK Online Services
Member-Exclusive Content

These contents can be accessed

after registering as a member.

Log in/Register Click here for THK Online Services details

Benefit 1: Useful features

  • Easy product comparisonsHighlight feature
  • Save items for laterreview Favorites feature

Benefit 2: Exclusive content

Products Contents
LM Guide LM rail standard lengths and maximum length, tapped-hole type LM rail, frame for LM rail clamps, steel plate for LM rail clamps, etc.
Ball Screw Axial clearance, maximum manufacturing length of shaft, etc.
Actuator Movable part mass, etc.