Pasek linii półksiężyca
PATEND PENDING
Revolution in crank hole finishing! Without special machine and special jigs!
High-mix multi-product production with one machining center
Line bars that help reducing capital investment
Processing by machining center reduces capital investment by approximately 60%
No need for expensive jigs
Enables high-mix multi-product production
Amazing facts!
── Introducing ideas and technologies ──
The crescent line bar consists of an unbalanced shape of the body and a special guide pad arrangement.
Centrifugal force generated during rotation controls the pressing pressure of the guide pads.
Since both end holes of the crank hole are used as guide holes, the support bushings of the jig are no longer necessary, enabling machining with a machining center.
Realizes “investment reduction” and “high-mix multi-product” production.
Reduced capital investment by eliminating the need for expensive jigs
Good
- Conventional method
Equipment specification:
dedicated machine + support jig
- Crescent line bar
Equipment specification:
General purpose machine (M/C) + inexpensive jig
This is the point!
Unbalanced shape and special guide pad arrangement
Excellent!
- Centrifugal force and cutting resistance caused by rotation presses the guide against the support hole, thereby aligning the center of the tool with the center of the support hole.
Tool cross-sectional shape
This is the point!
Supported by guide pad and workpiece end holes
Excellent!
This is the point!
With floating function
Excellent!
Supports both parallel and tilted directions
Parallel floating
Tilt floating
Machining cycle
①
5J finishing (short tool)
②
Work rotation
③
1J finishing (short tool)
④
4J finishing (Crescent line bar)
Development / product concept
“Current status and challenges”
- The crank hole in the cylinder block is an important part of the product function and requires strict coaxiality.
For this reason, “dedicated equipment”, “dedicated support jigs”, and “dedicated long line bars” are used in general. - These facilities require high capital investment, and it is difficult to handle high-mix multi-product production.
“Development points”
- The Crescent Line Bar has realized an epoch-making method that uses holes at both ends of a workpiece as reference guide holes to ensure machining accuracy on a machining center.
- It contributes to “investment reduction” and “high-mix low-volume production” by providing machining accuracy equivalent to that of dedicated equipment.
- The product name is derived from the fact that the body is removed in a crescent shape to create an unbalance.
Processing example
Tool used
Crescent line bar
Equipment used
Machining work
Work material
JIS FCD500 / EN-GJS-500-7 / DIN GGG50
+
JIS ADC12 / ENAC-AlS11Cu2(Fe)
Tool diameter
ø68 mm +0,022/-0,002
Cutting conditions
Spindle speed: n = 700 min-1
Cutting speed: Vc = 150 m/min
Feed: f = 0.1 mm/rev
Machining allowance
ø0.2 mm
Coolant
internal through coolant
Coaxiality
Roundness
Product specifications
- Tool specifications
Tool name
Crescent line bar
Target process
Cylinder block crank hole finish *1
Setting diameter
ø65 mm～
Standard conditions
Feed: f = 0.1 mm/rev
Coaxiality
Within 10 µm
- (Short) finishing tool for both end journals is required separately.
- The limit of rotation speed varies depending on the machining diameter and tool length.
- Example of applicable work
