The eye of coin sorter/coin counter – alloy sensor.

Alloy sensor, an essential part of a coin sorter, reads the information of every coin that goes through the machine, including its geniuses, denomination, quantity, etc. The alloy sensor accurately collects and transmits the feedback to the central processing unit of the machine.

The alloy sensor is an application of Eddy Current Principle, and it has been commonly and widely used in the market. Compared with other types of displacement sensors, the eddy current sensor has advantages of long-term reliability, wider measuring range, higher sensitivity, higher resolution, faster response speed and is unaffected by oil pollution. It is now popular in power, petroleum, metallurgical and more other industries.

Ribao's coin sorter/coin counter use alloy sensor in order to detect 3 main characteristics of coin: its material, diameter and thickness. Therefore, we extract 3 groups of parameters from our detection according to different emission frequencies. Then we combine the 3 sets of parameters we get with software algorithms to distinguish and to form more parameters to reflect the characteristics of coins.  

For customers, a good machine not only need to have multiple functions, but also needs to be reliable. We have devoted tons of effort on the consistency and durability of the sensor.

For consistency, we replaced the Metal plectrum in the sensor with a German imported material after realizing our previously used domestic material cannot provide enough stability. The accuracy of parameters highly depends on the uniformity of the material as low uniformity of the material and its thickness can lead to high uncertainty in the sensor’s feedback. At the same time, we also use double-coated self bonding enamel wire to wind our metal coil. It has an advantage of lowering the electromagnetic interference of the coil, and therefore guarantees the consistency of performance. After a sensor has been made, Ribao arrange a special testing platform to make sure the parameters detected by the sensor is within our required range. Sensors that do not meet the requirement will be rejected as unqualified products. Only the ones that satisfy the requirement can be put into use.

The second part is durability of our machine. Our sensors go through a potting process to make sure they are fully sealed and isolated from external environment. The key in this process is the use of epoxy adhesive. The coefficient of thermal expansion of epoxy glue is relatively small so the impact of environmental temperature will also be very little on the performance of the metal sensor. In addition, we carry out  High-low temperature aging test, vibration test, insulation test, etc. against our finished metal sensor to further screen and ensure the reliability and durability of our coin sorter/coin counter.

Our coin sorter can now be used to recognize 67 currencies around the world. All counterfeit coins on the market can be identified through 3 sets parameters. In general, all counterfeit coins have discrepancies in materials. The diameter and thickness of coins are easy to duplicate but the materials are confidential parameters. The mixing percentage of various materials makes it difficult and costly to duplicate. As a result, material identification is commonly used to detect counterfeit coins. For multiple currencies (currencies of multiple country), all 3 parameters are used, some are different in diameter, some are different in size, some are different in materials.

In summary, the metal sensor has similar functions of human eyes. It recognizes every coin that passes through its sight and transmits the information to the main control center, allowing the control center to determine whether it is suspicious and whether it should be removed. This is the core function of the metal sensor.

Related:

6 Factors To Consider When Buying The Best Coin Counting Machine

Current application of metal sensors on our machine:

CS-211S，2-pocket coin counter CS-211S

CS-610S+PRO，6-pocket coin sorter CS-610S+PRO

CS-910S+, 9-pocket coin sorter CS-910S+

Metal sensor of a coin sorter

Small generator

Material/diameter/thickness

3D graph of coin parameters

Metal plectrum

Coil

Ribao quality test center testing sensors