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De La Rue Coin Counting Machine

Here’s some teardown photos of an old De La Rue coin counter, used in businesses for rapid counting of change into large bags.

Mechanism
Mechanism

An overview of the whole mechanical system of the counter. Coins are loaded into the drum at the rear of the machine, which sorts them into a row for the rubber belt to pick up & run through the counter. The coin type to be sorted is selected by turning the control knobs on the right.
The control knobs adjust the width & height of the coin channel so only the correct sized coins will be counted.

PSU & Switching
PSU & Switching

The counter is driven by a basic AC induction motor, the motor power relay & reversing relay is on this PCB, along with the 5v switching supply for the main CPU board.
The SMPS on this board looks like a standard mains unit, but it’s got one big difference. Under the frame next to the main motor is a relatively large transformer, with a 35v output. This AC is fed into the SMPS section of the PSU board to be converted to 5v DC for the logic.
I’m not sure why it’s been done this way, and have never seen anything similar before.
The edge of the coin channel can be seen here, the black star wheel rotates when a coin passes & registers the count.

Controller PCB
Controller PCB

Here’s the main controller PCB, IC date codes put the unit to about 1995. The main CPU is a NEC UPD8049HC 8-bit micro, no flash or EEPROM on this old CPU, simply mask ROM. Coin readout is done on the 4 7-segment LED displays. Not much to this counter, it’s both electronically & mechanically simple.

Counter Sensor
Counter Sensor

Coin counting is done by the star wheel mentioned above, which drives the interrupter disc on this photo-gate. The solenoid locks the counter shaft to prevent over or under counting when a set number of coins is to be counted.

Motor Run Capacitor
Motor Run Capacitor

Under the frame, here on the left is the small induction motor, only 6W, 4-pole. The run cap for the motor is in the centre, and the 35v transformer is just visible behind it.

Main Motor Drive
Main Motor Drive

Main drive to the coin sorting mech is through rubber belts, and bevel gears drive the coin drum.

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Audi TT Roof Hydraulics

Pump
Pump

This is the hydraulic system from an Audi TT that would power the soft top. Here is the hydraulic pump unit. Oil Tank is on the left. Power is 12v DC at ~20A

Cylinders
Cylinders

The pair of hydraulic cylinders that attached to the roof mechanism.

Limit Switch
Limit Switch

One of the cylinders has a limit switch built in. The brass bolt coming out of the side of the head is one contact. The other contact is the cylinder body.

Hose
Hose

Marking on the hoses. This is Parker Polyflex hydraulic hose. 1/8″ ID.

Motor
Motor

Drive motor for the hydraulic pump. Standard DC permanent magnet motor.

Motor Suppression
Motor Suppression

Motor power terminals & suppression capacitors. As the reversing relays actually short the motor out when de-energized, there is a lot of arcing at the brushes without some suppression.

Reversing Relays
Reversing Relays

Reversing relay stack. Each relay is a SPDT configuration. The pair are arranged as a DPDT bank to reverse the motor, depending on which relay is energized.

Tank
Tank

Detail of the oil tank showing the level markings.

Power Valve
Power Valve

Solenoid valve on top of the unit. This valve provides full pump pressure to the cylinders when energized.