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| HRBN offers Super Linear Ball Bushing as a new standard in linear motion bearings. This Super Linear Ball Bushing has 3 times load rating and 27 times travel life of conventional linear bushings. Also, HRBN Super Linear Ball Bushing offers Alignment which can give you less installation time and can prolong the travel life by reducing the friction between the shaft and balls. Super Linear Ball Bushing is designed to meet any customer's demands such as factory automation equipments, industrial machines, electrical equipments, measuring instruments, and etc. HRBN Super Linear Ball Bushing will give you the benefit of total cost reduction and improvement of your machine performance. |
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| Super Linear Ball Bushing Features |
Higher Load Ratings
Uniquely designed ball plate is made by hardened steel, and the precisely ground groove is slightly larger than ball size which provides greater contact area between the ball and the ball plate. And, this design provides 3 times higher load ratings of the conventional linear bushing.
Self Alignment
Ball plate has a convex shape to provide a pivot point at the center which allows self alignment up to 0.5°. This self alignment capability eliminates any possibility of edge pressure caused by inaccurate machining, errors on mounting, or shaft deflection.
Longer Travel Life
HRBN Super Linear Ball Bushing offer three times the load rating or 27 times travel life of conventional linear bushing.
Smooth And Silent Motion
Super Linear Ball Bushing has extremly smooth motion due to the uniquely designed ball ratainer and the outer sleeve. They are made of engineering polymer, which has light weight, low friction, and high wear-resistance. Due to them, smooth and silent motion can be obtained.
Clearance Adjustment
Super Linear Ball Bushing's ball plates are designed to float in the outer sleeve. This allows the clearance between the balls and shaft to be adjusted for the best applicantion environment by using with the Clearance Adjustable housing.
Interchangeability
Super Linear Ball Bushing is designed to be fully Interchangeable with conventional linear bushing.
Lower Cost
Self alignment feature can compensate the inaccurate machining of the base. so less installation time and lower cost can be obtained.
Higher Load Rating And Longer Travel Life
Compared to the same size conventional linear bushing, Super Linear Ball Bushing offers higher load rating and longer travel life.
Reduction of Material Cost
Super Linear Ball Bushing's higher load rating enables the use of smaller components, and reducing material cost.
Energy Saving
Super Linear Ball Bushing is deaigned to be light weight, lower inertia, and low friction, So it enables the moving parts to have rapid motion with lower driving power.
| Super Linear Ball Bushing |
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Standard type (not Sealed)
Floating ball plate features offer self alignment and clearance adjustment, and light weight retainer and outer sleeve offers silent operation. |
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Open Type
One ball circuit is removed from the outer sleeve to be used with bottom supported shaft for deflection free movement. This open type Super Linear Ball Bushing also has self alignment and clearance adjustment. |
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Standard type (Sealed)
Specially designed integral wiper seals create a free floating action in the outer sleeve. It provides perfect sealing ability during self aligning operation. |
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Suoer Linear Ball Bushing's part number notation is as follows:
| Load Ratings and Travel Life |
Super Linear Ball Bushing's load ratings give an influence to travel life with load direction, ball circuit orientation, and hardness of the shaft.
Basic Dynamic Load Rating (C) and Travel life
The travel life of a Super Linear Ball Bushing is determined largely by the quality of the shaft. The basic dynamic load rating is maximum continuous load that can be applied to the Super Linear Ball Bushing with 90% of reliability achieving after 50km operation under normal conditions. The nominal travel life can be calculated by following equation.
Practically, other factors will affect life as follows:
From the above equations, when the stroke and frequency are constant, the travel life can be calculated by following equation:
Calculation example:
The Maximum applied load and the travel life are the most important factor for choosing a proper size of Super Linear Ball Bushing. Belows are the sample calculation of the expecting travel life and choosing a proper size of Super Linear Ball Bushing.
—— Working conditiond ——
· Applied load： 250N（P）
· Stroke ： 0.250m（Ls）
· Number of strokes per minute ： 60（Nr）
· Shaft hardness ： HRC 60（hr＝1.0）
· Operating speed ：
other factors （fc、ft）are considered as 1.0
Calculation of expected travel life:
Assuming the basic dynamic load rating is based on travel life of 50km and all other factors are 1.0, you choose the Super Linear Ball Bushing size that you can expect travel life.
Let's try LMES20UU with the above working conditions.
Choosing a proper Super Linear Ball Bushing
Let's assume out design travel life is 15,000 hours:
So, the proper Super Linear Ball Bushing for above condition is LMES25UU which has 3,800N as the basic dynamic load rating.
To optimize the performance of the HRBN Super Linear Ball Bushing, high precision shaft and housing are required.
Housing
For Super Linear Ball Bushing's application, housing is required, and the tolorance of housing bore will affect the life and the accuracy of application. See Table 9 and Table 10.
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Table 9 Recommended toleranced between shaft and housing (ISO Standard)
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Part Number
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Shaft
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Housing
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shaft Dia.
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Tol.（h6）
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Housing Bore
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Tol.（H7）
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d（mm）
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μm |
d（mm）
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μm |
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LMES10 |
10 |
0 -9 |
19 |
+21 0 |
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LMES12 |
12 |
0 -11 |
22 |
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LMES16 |
16 |
26 |
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LMES20 |
20 |
0 -13 |
32 |
+25 0 |
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LMES25 |
25 |
40 |
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LMES30 |
30 |
47 |
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LMES40 |
40 |
0 -16 |
62 |
+30 0 |
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LMES50 |
50 |
75 |
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Table 10 Recommended toleranced between shaft and housing (Imperial Standard) unit: inch |
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| Part Number |
Shaft |
Housing |
| shaft Dia. |
Tol.（g6） |
Housing Bore |
Tol.（h7） |
| LMBS4 |
.2500 |
-.0002 to -.0006 |
.5000 |
0 to +.0007 |
| LMBS6 |
.3750 |
-.0002 to -.0006 |
.6250 |
0 to +.0007 |
| LMBS8 |
.5000 |
-.0002 to -.0007 |
.8750 |
0 to +.0008 |
| LMBS10 |
.6250 |
-.0002 to -.0007 |
1.1250 |
0 to +.0008 |
| LMBS12 |
.7500 |
-.0003 to -.0008 |
1.2500 |
0 to +.0010 |
| LMBS16 |
1.0000 |
-.0003 to -.0008 |
1.5625 |
0 to +.0010 |
| LMBS20 |
1.2500 |
-.0004 to -.0010 |
2.0000 |
0 to +.0012 |
| LMBS24 |
1.5000 |
-.0004 to -.0010 |
2.3750 |
0 to +.0012 |
| LMBS32 |
2.0000 |
-.0004 to -.0012 |
3.0000 |
0 to +.0012 |
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Shaft
Because the balls in HRBN Super Linear Ball Bushing as rolling elements are running directly on the shaft surface, the hardness, surface finishing, and tolerance of shaft will largely affect the travelling performance of Super Linear Ball Bushing.
The shaft：
1)Hardness
The hardness must be HRC 58 to 64.
The shaft hardness below HRC 58 will lead decreasing of travel life and permissible load.
2) Surface Finishing
The Surface finishing must be 1.6S or better for the smooth operation.
3) Tolerance
The correct tolerance of the shaft diameter is recommended as shown on Table 9 and Table 10.
Fitting
Recommended fittings between Super Linear Ball Bushing and shaft are shown in Table 9 and Table 10.
Please note when the housing bore tolerance is H7, there are tight fit at the both ends of outer sleeve of metric trpe.
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