Crankshaft Bearing Cap Tightening Machine
We developed this particular machine for our client to assist with the engine block manufacture. This machine was semi-automatic with staged assembly over a small linear conveyed system. Each engine block needed to be scanned into the system and all tightening results logged onto a quality system.
The system features a Bosch TS2 Conveyor that transfers the Engine Block through the process via a series of profiled lightweight platens.
Servo drives have been utilised to adjust the spindles for pitch and for the client’s different fixings. A pair of spindles is used on each cap simultaneously to give the required cycle time due to the extensive tightening sequence required (Snugging, pre tighten, tighten to torque etc.). The servo system now provides greater flexibility and extended capability by allowing approximately 10mm additional movement than is currently required (existing clients processes) to cater for some future proofing.
The two Bosch DC spindles are installed complete with a 2 multi way system box and associated control cards. The Station is independently controlled and monitored by its own Bosch Indralogic PLC, talking natively with each spindle and servo positioning motor.
In detail the machine comprises of the following equipment: –
The Bosch Rexroth TS2 Conveyor is a work-piece pallet based, non-synchronous module, designed to improve manufacturing productivity and product quality while allowing for maximum assembly flexibility. The Conveyor meets the needs of the assembly process and features the following:
• Workpiece pallets specifically designed for the product sizes
• A high maximum load of up to 100 kg per workpiece pallet
• Workpiece pallet sizes: 640 x 480 mm
• Pallet Stops
• Pallet Lifts
At entry end of the machine a manual poke yoke (error checking) fixture is suspended on a pivot arm to allow the system to be moved out of the way for loading of the block by the hoist. The operator positions the system over the block, lowers and locates onto hollow dowels pre-fitted to the Crank Block. Once in position (detected by sensors) a test cycle is initiated by the operator to detect if the plungers are pushed back (if the set screws and Bearing Caps are in position) indicating an OK part. If one plunger is not sensed a not OK condition occurs and a fault lamp warns the operator.
The next stage is tightening, this comprises of a series of Bosch Rexroth Drive Spindles that are either dedicated or formatted to engage with the fixing screws of the Crankshaft Bearing Caps and provide a calculated torque rating (Tighten) and positive feedback that the task has been completed. Where there is a variable cross position for the screws to be driven, a servo controlled head adjustment is provided to shuttle between the variants. The Multi-tool has two spindles each with a working range between 42 and 200 Nm with a spindle bearing, offset output drive and feed output drive configured for a tightening programme to suit the requirements of the Crankshaft Bearing Cap fixing. The multi-spindles have the ability to adjust to the different pitches and positions by use of a four axis servo system. The final stage offered a lift and rotate platen turntable to operate on the fixings, either side of the block.
Door Magazine Loader
Our client had a requirement to replace a troublesome piece of apparatus that had been in operation for over 25 years. They had a storage magazine that holds the sets of vehicle doors until they are required to be released to the door build conveyor line. The doors are removed from the vehicle and placed into a sling and trolley unit which transports them to a storage magazine via an overhead mono rail system (EMS).
Once the sling and trolley unit arrives at the storage magazine the sling is unloaded from the trolley by means of a pneumatically driven pickup arm which intern is pneumatically driven to and from the storage magazine.
The problem areas identified were the reliability handling (risk of dropping a sling) and the propulsion method via a pneumatic rod less cylinder. This has very limited speed control and has no back-up should it fail.
We designed twin-belt drive system with localised motor/speed control via SEW Movifit-FC drives. The system would normally operate using two chain coupled link belt shafts to propel the transfer arms back and forth. In an event of failure fatigue to one of the belts, the system could manage on a single belt with minimum disruption to production till a time when the failed belt can be replaced.
In using these drives the speed and movement was profiled to achieve maximum transfer speed with a smooth operation eliminating the risk of any sling droppage and damaged doors.
Built into the system was the ability to swap the motor/drive set to a standby set fitted locally reducing the amount of downtime seen for a bottleneck piece of apparatus.
Old Loading Mechanism …
New Improved Loading Mechanism …
Component Handling Gantry Transfer System
Our client’s customer highlighted to them a quality concern, these shafts might be mishandled and not balanced checked. This required a controlled product handling system to feed assembled shaft from the assembly area to the balancing machine. ESA provided a gantry based solution due to the distances the product had to traverse.
The Gantry System is divided into two sections, one for picking a shaft out of the assembly rig and loading the either one of buffer stations and the second gantry gripper transfers from this buffer to the balancing machine. This buffer area provided the operator with no bottle necks as he could build a batch whilst the balancer performed its duties.
Both the storage buffer and transfer slides of the both gantries consist of Bosch Rexroth aluminium extrusion and linear slides and components. For a smooth and fast operation each gantry transfer utilised a combination of pneumatic and servo control technology.
Local buffer stands …
Gantry traversing into balancing machine area …
Cam Cap Tightening Machine
The machine was designed to perform the tightening of the Cam Caps to the cylinder head for our client. Built around a small footprint the process utilises four DC spindles on a set linear, servo driven slides to keep overall cycle times to a minimum with minimum operator intervention and cost.
The solution encompasses Bosch Rexroth TS2 conveyor that transfers the cylinder head (L/H or R/H) through the varying processes. Servo drives have been utilised to adjust the spindles for pitch and also for the different fixings and different L/H or R/H Head cap positions. A pair of spindles is used on each cam simultaneously (2 sets of twins) to give the required cycle time due to the extensive tightening sequence required. (Snugging, pre tighten, tighten to torque etc.). The servo system now provides greater flexibility and extended capability by allowing approximately 10mm additional movement than is currently required to cater for some future proofing. The four Bosch DC spindles are installed complete on individual Bosch servo controlled linear slides with a 4-way system box and associated control cards.
The load area of the machine houses a vision system for verifying the correct cam caps have been fitted to the cylinder head has been installed. The Cognex IS7000 series vision system uses a series of pattern match routines to verify each cap, screw and mandrill are present and correctly fitted, before any further actions can be done. The system will be configured to work with both the right hand and left-hand
cylinder heads with out the need for manual selection (done by data matrix code interrogation).
This tightening process comprises of a series of Drive Spindles from Bosch Rexroth that are either dedicated or formatted to engage with the fixing screws of the Cam Caps and provide a calculated torque rating (tighten) and positive feedback that the task has been completed.
Where there is a variable cross position for the screws to be driven, a servo controlled head adjustment is provided to shuttle between the variants. The multi tool has four spindles each with a working range between 42 and 200 Nm with a spindle bearing, offset output drive and feed output drive configured for a tightening programme to suit the requirements of the Cam Cap
A Pryor marking system mounted to XYZ slide gave the manoeuvrability to adjust for each cap position to permanently mark this cap positions for a later process. This forms the last stage of the machine.
Small Component Induction Heating
Our client approached ESA to develop a small heating assembly rig to allow each turbo compressor wheel to be pre-heated so that this wheel could be pressed tightly onto the core shaft. The purpose of this equipment is to facilitate heating the component via induction through temperatures of 130-330 degrees.
The definition for this induction heating process states:
Induction heating is the process of heating an electrically conducting object (usually a metal) by electromagnetic induction, through heat generated in the object by eddy currents (also called Foucault currents). An induction heater consists of an electromagnet, and an electronic oscillator that passes a high-frequency alternating current (AC) through the electromagnet. The rapidly alternating magnetic field penetrates the object, generating electric currents inside the conductor called eddy currents. The eddy currents flowing through the resistance of the material heat it by Joule heating. In ferromagnetic (and ferromagnetic) materials like iron, heat may also be generated by magnetic hysteresis losses. The frequency of current used depends on the object size, material type, coupling (between the work coil and the object to be heated) and the penetration depth.
Induction heating allows the targeted heating of an applicable item for applications including surface hardening, melting, brazing and soldering and heating to fit.
Our process utilised converter unit capable of producing high frequency energy for heating purposes by an self supporting resonant circuit driving a transformer and a series of transistor outputs at varying frequencies between 250Khz – 1 Mhz. Coupled with a water cooling unit providing constant chilled water to a given level that flows throughout the heating pipe network and provides longevity for the heater coil, by rapidly cooling the coil when not in use.
The part is held in place till the desired temperature is reach, retained in place by a locking mechanism. Temperature is kept constant via a PID control loop.
Tunnel Equipment Lift Assistor
Our client asked us to come up with a low cost simple to use piece of lifting equipment for use underground in completing all the tunnel lifting and signage. This had to be able to elevate a set load to the curved tunnel ceiling.
We had the following brief …
Support unit to be attached to existing platform capable of holding a 20 kg fabrication and providing ‘X Y’ movement +/- 25 mm in both direction. To have a vertical lift of 400mm and to mounted on a slide unit to allow the assembly to traverse the existing platform by =/- 1,250mm. The system must be easy to operate and all axes must have a restriction in movement (lock in position)
The system has a cantilever arm on a linear rail to allow the traversing of the arm 1400mm up and down the platform. This is held in position on the linear rail by a simple mechanical screw lock. On the end of the cantilever arm is a screw jack complete with linear guide to stop rotation and system lock. The unit will allow the raising of the tooling the required 400mm. (This can be achieved by a battery drill to speed up the process)
On top of the screw jack is an X Y table which will allow movement in the X and Y +/- 25mm again a simple mechanical screw lock will hold the table in the set positions.
On top of the table is the assembly mounting plate which consists of a square steel block to allow the cable support assembly to be placed over the block and hold it in the required position for fixing to the tunnel roof.
Wheel-bolt Multi Spindle Tightening Solution
Our client came back to us for a new Wheel-bolt Multi, they were so happy with their previous system they asked us to provide another one with more functionality.
They required their new system to incorporate the following …
• Wheel multi is to be constructed in a light weight material, for example, aluminium, carbon fibre etc.
• Wheel multi to be of robust construction to maintain volumes of vehicles at present & in future.
• New wheel bolt tool will be suspended on existing demag down shop rails new KBKII bridge rails (or similar) are required (Approx. 4m)
• Angle of wheels on cradles differs from vehicle type, the current variation ranges from 1o to 6o. The requirement is to alter angle of approach of the wheel bolt multi from 1, 3 , 6, 10 degrees from horizontal.
• Automatic height adjustment (up & down) is also necessary this will need to be set by PLC to meet vehicle spec which will be identified by the vehicle VIN No.
• Half-moon style wheel at front of wheel bolt multi (to reduce weight). Start button (handle) to mounted one sides to include up down control buttons.
• Suspension trolley to be light weight (Aluminium) this is to be suspended below new KBKII bridge rails
• Raise lower of wheel bolt to be via a pneumatic cylinder 400mm stroke requested – (min of +/- 100mm ie 200mm required however +/- 200mm preferred)
• Suspension trolley is to be positioned to vehicle by operator and locked to wheel – Currently by 2 cylinders – 1 to lower lock in position 1 to lock trolley forward, concept works well
• Suspension trolley to be removed from vehicle automatically after tightening complete – (min 750mm drag back) currently done by rod-less cylinder again concept works well.
• UP DOWN AND ANGEL TO BE SENSED by sensors only
• Ultimate up and down limit required
• Wheel bolt tool cover guard to be light weight construction