Logo

JUCAM

JUCAM - Non-circular grinding machines

Purely a matter of form

The OD/ID grinding machines of the JUCAM series impress with precise grinding results in a single clamping set-up. Thanks to the control system with learning function – with which virtually all disturbing variables are compensated – camshafts, cam pieces and individual cams are given a perfect finish. The many decades of experience in grinding cams, the many special solutions and the resulting expertise in finding solutions convince engine and pump manufacturers the world over.

Highlights

  • Broad range of grinding solutions for camshafts, cam pieces and individual cams
  • Non-cylindrical OD/ID grinding
  • High utility value through adjustment to respective grinding assignment
  • High long-term precision due to hydrostatic round guides
  • Maximum repeat accuracy thanks to CBN or diamond abrasives
  • Minimized undulations due to grinding wheel balancing on two levels

Grinding process descriptions

OD/ID grinding

Grinding machines for grinding camshafts, cam pieces and individual cams combine non-cylindrical grinding for the cams and cylindrical grinding for the bearings. With non-cylindrical OD/ID grinding, the grinding wheel follows the cam contour through interpolation of the workpiece spindle (C-axis) with the grinding spindle (X-axis). CBN or diamond are used as an abrasive – for high cutting performance with a constant level of quality and a long tool life.

The cam geometry is specified in a lift table. In the process, each angle is assigned a lift value to define the cam contour and import it to the program. The software then interpolates the values automatically. The cam contour is frequently concave in the infeed and discharge area. Here the concave radius determines the maximum grinding wheel diameter that can be used.

OD/ID grinding

Inside round grinding

External cylindrical grinding

Technical data: JUCAM 1S

Wheelheader Number
1
Grinding Length
150 mm
Clamping Length
150 mm
Center Height
100 mm
Component Weight
5 kg
Grinding Wheel Diameter
350 mm
Swing Diameter
80 mm
WxDxH mm (without peripherals)
1800 x 2500 x 2100
Weight
10000 kg

Wheelhead JUCAM 1S

  • /10
    /10
  • /11
    /11
  • /20
    /20
  • /50
    /50
  • /51
    /51
  • /18
    /18
  • /52
    /52

Technical data: JUCAM 1000

Wheelheader Number
1
Grinding Length
150 mm
Clamping Length
150 mm
Center Height
100 mm
Component Weight
5 kg
Grinding Wheel Diameter
350 mm
Swing Diameter
80 mm
WxDxH mm (without peripherals)
1500 x 2500 x 2100
Weight
9000 kg

Wheelhead JUCAM 1000

  • /10
    /10
  • /11
    /11
  • /20
    /20
  • /50
    /50
  • /51
    /51

Technical data: JUCAM 3000

Wheelheader Number
1
Grinding Length
400 mm
Clamping Length
400 mm
Center Height
150 mm
Component Weight
15 kg
Grinding Wheel Diameter
400 mm
Swing Diameter
150 mm
WxDxH mm (without peripherals)
3400 x 2800 x 2200
Weight
12000 kg

Wheelhead JUCAM 3000

  • /10
    /10
  • /11
    /11
  • /20
    /20
  • /50
    /50
  • /51
    /51
  • /60
    /60
  • /61
    /61

Technical data: JUCAM 5000

Wheelheader Number
1
Grinding Length
700 mm
Clamping Length
700 mm
Center Height
170 mm
Component Weight
130 kg
Grinding Wheel Diameter
500 mm
Swing Diameter
280 mm
WxDxH mm (without peripherals)
4900 x 3400 x 2350
Weight
17000 kg

Wheelhead JUCAM 5000

  • /10
    /10
  • /11
    /11
  • /20
    /20
  • /50
    /50
  • /51
    /51
  • /61
    /61
  • /60
    /60

Technical data: JUCAM 6XS

Wheelheader Number
1
Grinding Length
500 mm
Clamping Length
600 mm
Center Height
170 mm
Component Weight
130 kg
Grinding Wheel Diameter
500/700 mm
Swing Diameter
280/320 mm
WxDxH mm (without peripherals)
3260 x 3750 x 2450
Weight
20000 kg

Wheelhead JUCAM 6XS

  • /10
    /10
  • /11
    /11
  • /12
    /12
  • /20
    /20
  • /50
    /50
  • /51
    /51
  • /60
    /60
  • /61
    /61

Technical data: JUCAM 6S

Wheelheader Number
1
2
Grinding Length
1000mm
750 mm
Clamping Length
1200 mm
Center Height
170 mm
Component Weight
150 kg
Grinding Wheel Diameter
500/700 mm
Swing Diameter
280/320 mm
WxDxH mm (without peripherals)
4100 x 3750 x 2450
Weight
25000 kg
28000 kg

Wheelhead JUCAM 6S

  • /10
    /10
  • /11
    /11
  • /12
    /12
  • /20
    /20
  • /50
    /50
  • /51
    /51
  • /60
    /60
  • /61
    /61

Technical data: JUCAM 6L

Wheelheader Number
1
2
Grinding Length
1800 mmm
1500 mm
Clamping Length
2000 mm
Center Height
170 mm
Component Weight
200 kg
Grinding Wheel Diameter
500/700 mm
Swing Diameter
280/320 mm
WxDxH mm (without peripherals)
4900 x 3750 x 2450
Weight
28000 kg
31000 kg

Wheelhead JUCAM 6L

  • /10
    /10
  • /11
    /11
  • /12
    /12
  • /20
    /20
  • /50
    /50
  • /51
    /51
  • /60
    /60
  • /61
    /61

Technical data: JUCAM 6XL

Wheelheader Number
1
2
Grinding Length
2800 mm
2500 mm
Clamping Length
3000 mm
Center Height
170 mm
Component Weight
300 kg
Grinding Wheel Diameter
500/700 mm
Swing Diameter
280/320 mm
WxDxH mm (without peripherals)
6400 x 3750 x 2450
Weight
31000 kg
34000 kg

Wheelhead JUCAM 6XL

  • /10
    /10
  • /11
    /11
  • /12
    /12
  • /20
    /20
  • /50
    /50
  • /51
    /51
  • /60
    /60
  • /61
    /61

Equipment and Options

CONTROL SYSTEM
Control system

The Erwin Junker Operator Panel was specifically developed to control grinding machines. All machine components are controlled using the operator panel – irrespective of the series and the used control system. The identical structure, intuitive menu guidance and visualization of the workpiece geometry make for extreme user convenience and flexibility in operation. Programming takes place directly using the operator panel or an external programming tool.

DRESSING UNIT
Dressing unit

Grinding wheel dressing is CNC controlled. A driven diamond dressing wheel or a workpiece-dependent diamond profile roller can be used. Dressing takes place manually or using an automatic dressing program with grinding wheel compensation.

LONGITUDINAL AND RADIAL POSITIONING
Longitudinal and radial positioning

In order to generate a precise width and angular position of the main and pin bearing, the position must be precisely determined when clamping the crankshaft. For this, a touch probe measures the radial position of the pin bearing and the longitudinal position of the main and pin bearing. The measured values are automatically integrated in the grinding process by the control system.

LEARNING FUNCTION
Learning Function

The control system comes with automatic compensation of runout and disturbing variables such as temperature influences, grinding allowance fluctuations or material changes. Even minimal deviations between the target and actual position of the grinding wheel are automatically corrected.

Axis drive and guidance
Axis drive and guidance

With platforms 1 to 8, the wheelheads traverse along the Z axis. The mechanical direct drive uses the rack and pinion to perform play-free positioning depending on both load and temperature – thanks to two drive motors per slide. With platforms 1000 to 5000, the grinding table traverses on a flat prism guide with pre-tensioned ball screw.

The X axis with hydrostatic round guide carries out stick-slip-free positioning with minimal wear and maintenance requirement – due to the absence of any metal contact between the guide column and housing. Drive takes place by means of an ultra-precise hydrostatic feed spindle which is suitable for extremely high forces and has no acceleration limit.

The B axis of the wheelheads is driven by a play-free gear or torque motor. Every angular position is programmable; the path measuring system has a sensational resolution of 0.00001 degrees. The directly driven grinding spindles – manufactured by JUNKER – ensure extremely low-noise running, with structure-borne sound sensor and dynamic balancing system on one or two levels.

C AXIS WITH DIRECT DRIVE
C axis with direct drive

Torque motors are used for direct drive of the C axis. This ensures impressive quiet running, high torque rigidity and superb dynamics in the C axis. Torsionally unstable crankshafts are driven by two C axes.

MACHINE BED
Machine bed - mineral cast

The machine bed made of mineral cast provides impressive damping behavior and torsional rigidity. The temperature stability allows fluctuations in the ambient temperature to be compensated with a minimum of effort, ensuring a high level of dimensional stability throughout the whole day.

Clamping fixture
Clamping fixture

The patented 3-point mounting interface allows grinding and dressing wheels as well as work holdings to be mounted and centered on grinding spindles, workpiece spindles and tailstock sleeves in record time. Adjustment of the tailstock and, where applicable, the workhead take place using optionally using a chain wheel, a hydraulic cylinder or a CNC axis with rack and pinion drive. An airlift function simplifies position adjustment. Depending on the workpiece, in addition a wide range of clamping systems are also available

ABRASIVE
Abrasive

Depending on the application, the abrasive CBN or diamond is used. The basic bodies of the grinding wheels comprise steel or carbon. In conjunction with CBN, it can make sense to use a carbon base body: It is light, has vibration-damping properties and remains dimensionally stable even at high speeds.

FIRE PROTECTION AND LTA AIR FILTERS
Fire protection and LTA air filters

In case of an fire, the machine interior is automatically hermetically sealed, suffocating a fire before it has a chance to spread. If required, extinguishers (CO² or water mist systems) and exhaust air purification systems can be additionally installed. A competent partner for fire protection and filtration solution solutions is LTA Lufttechnik GmbH, which also belongs to the JUNKER Group and which researches, develops and produces filtration systems for industrial air purification.

LOADING SYSTEMS
Loading systems

JUNKER offers both internal and external loading systems for all its machine series, depending on customer and workpiece requirements. The loading systems can be combined with different infeed and discharge systems such as conveyor belts or custom tailored systems.

MEARSUREMENT SYSTEMS
Measurement systems

The measurement systems are also individually adjusted to the various workpieces and customer specifications. The measurement processes entail evaluating the recorded measured values and utilizing them for measurement correction in line with the prepared measurement strategy. A grinding wheel measuring system to determine the diameter, axial position and width of the grinding wheel completes the wide range of systems on offer.

IN-PROCESS MEASURING SYSTEM
In-process measuring system

A swivel-in measurement probe carries out an in-process measurement of the diameters of the main and pin bearing. The control system logs the measured values, calculates
the correction data and generates the precise shape. After grinding, the Machine is able to measure the entire geometry of the crankshaft – depending on requirements:
from the bearing width through the lift height to the taper of each element.

STEADIES
Steadies

As an option, self-centering three-point steadies ensure stable support. Tracking hydraulic jaws guarantee a balanced ratio of forces at all three support points, and with it a grinding process with repeat accuracy.

Workpieces

  • cam
  • Piston ring
  • Cam piece
  • Camshaft
  • Camshaftbushing
  • Pump cam
  • Piezoceramic actuators

Product Brochures

JUCAM.pdf

Special solutions

Cam pieces

Cam pieces

When grinding cam pieces, it is essential that the exact angular reference to the inner toothing is ensured. For this reason, the JUCAM clamps the cam pieces with an inner clamping mandrel. The longitudinal and radial positioning and the C-axis with direct drive result in a smooth, transition-free shifting surface.

Double workhead

Double workhead

The workhead with two opposing clamping devices minimizes the downtime when grinding individual cams and cam pieces: While grinding is being carried out on one side, unloading and loading, clamping and positioning are carried out on the other. The only downtime: Swiveling by 180 degrees in less than 3 seconds.

Grinding wheel sets

Grinding wheel sets

The use of grinding wheels sets is ideal for grinding cams with the same orientation. Several cam contours are ground simultaneously in one operation, which considerably reduces the cycle time. Carbon base bodies are also available for saving weight.

To the top
Back to list view

Address:

Erwin Junker Maschinenfabrik GmbH
Headquarters
Junkerstraße 2
77787 Nordrach
Germany