THK Linear Block
The THK linear block is one of the core components of the device, and its function is to guide and support. In order to ensure high machining accuracy of the machine, the linear guide rail is required to have high guiding precision and good motion stability.
THK linear block is a very high-precision tool in the automation industry, which requires the support
of the fixed components of the THK rail slider itself, so it is very important to say that its own fixed
What is the function of the fixed original of the linear guide? In fact, this is very simple. The guide rail
has no mounting holes. If it is not fixed, the guide rail will run. The fixed original will play a fixed rail
without shaking and shaking.
A linear guide can be understood as a kind of rolling guide, which is an infinite rolling cycle between
the block and the guide rail, so that the load platform can easily move linearly along the guide rail with
high precision, and the friction coefficient is reduced to the ordinary conventional sliding guide. One-fifth
of the size can easily achieve high positioning accuracy. The design of the block and the end of the rails
allows the linear guides to withstand loads in both directions, up and down, and the patented reflow
system and simplified structural design allow the THK linear block to have smoother and less noisy
In order to facilitate the splicing and debugging of the precision THK linear block, we divide the
process into two steps of coarse tuning on the precision guide rail. THK linear block coarse adjustment
We use the wire drawing method, a block is placed on the rail, and a reading microscope with a scale is
also installed on the block. The lens of the microscope should be aligned with a wire with a diameter of
0.3 mm, and the lens is placed vertically. Fix the steel wire at one end of the rail, and hang a heavy
hammer through the pulley at the other end, then adjust the ends of the steel wire so that the wire
overlaps the scribe line on the lens when the microscope is at both ends of the rail. At this point, the wire
is already an ideal straight line in the horizontal plane, in other words a reference. Move the slider to
check the straightness of any position on the rail and adjust it until the full length of the rail is within the
range of 0.3mm in the horizontal plane. Then, use the matching method to install the precision guide rail.
At this time, the straightness of the precision guide rail in the horizontal plane is within the range of 0.3
mm, which brings convenience for further adjustment.
Compared with the planar guide rail, the geometry of the cross section of the linear guide is more
complicated than that of the flat guide. The reason for the complexity is that the groove needs to be
machined on the guide rail to facilitate the movement of the sliding element. The shape and number of
the groove depend on the machine tool to be completed. The function. Instead of an intermediate
medium between the moving element and the fixed element of the linear guide, a rolling steel ball is
used. Because the rolling steel ball is suitable for high-speed movement, small friction coefficient and
high sensitivity, it can meet the working requirements of moving parts, such as tool holders and carriages
of machine tools. The basic function of the fixed element (rail) of the linear guide system is like a bearing
ring, a bracket for mounting a steel ball, and the shape is a "v" shape. The bracket wraps around the top
and sides of the rail.
How to install THK linear block
The burrs, dirt and surface scratches on the mechanical mounting surface must be removed before
installing the linear guide.
Note: THK linear block is coated with anti-rust oil before the official installation. Please clean the
reference surface with cleaning oil before installation. Usually, after the anti-rust oil is removed, the
reference surface is more likely to rust, so it is recommended to apply. Lubricating oil for the spindle with
The second step:
Gently place the main rail on the bed and use a side fixing screw or other fixing fixture to gently fit the
rail to the side mounting surface.
Note: Before installation, please make sure that the screw holes are in agreement. If the working holes
of the base are not matched and the bolts are forcibly locked, the combination accuracy and quality of
use will be greatly affected.
Slightly tighten the positioning screws of the slide rails from the center to the sides to make the rails
slightly fit the vertical mounting surface. The order is tight from the center position to the ends to obtain
a more stable accuracy. After the vertical reference surface is slightly tightened, the locking force of the
lateral reference surface is strengthened, so that the main rail can be surely fitted to the lateral reference
The fourth step:
Use a torque wrench to slowly tighten the positioning screws of the slide rail according to the
tightening torque of various materials.
The fifth step:
Install the sub-rails in the same way as the installation, and install the slides individually to the main
Note that after the THK linear block is installed on the slide, many subsequent accessories cannot be
installed due to limited installation space. It is necessary to install the required accessories at this stage.
(The attachment may be a grease nipple, a tubing joint, or a dustproof system.)