JPH0441781B2 - - Google Patents

Description

[Detailed Description of the Invention] (Technical Field of the Invention) This invention relates to a material sensor for an object.
In particular, the present invention relates to a coin material sensor with a temperature guarantee function for high-speed coin processing machines, for detecting the material of coins moving at high speed in passages in coin processing machines such as coin counting machines and coin wrapping machines.

(Technical background of the invention and its problems) Various types of material sensors have been considered and put into practical use to detect the material of an object, such as a coin. The material of the coin is detected, but the speed of the coin passing through the coin sorting section is relatively slow and the coin moves reliably to the regulation surface, so the output from the material sensor is stable. There are no particular problems. However, coin processing machines such as coin counting machines and coin wrapping machines have come to process coins at high speed, and until recently, coins had not been sorted using material sensors. This is because such coin processing machines are often used in financial institutions such as banks, and it was thought that counterfeit coins would not normally be brought into financial institutions.

However, due to the recent popularity of TV games, some of the coins brought in from game centers etc. are counterfeit coins (for example, coins that have the same diameter as genuine coins but have a different thickness and material; for example, 50 yen coins wrapped with solder and soldered to 100 yen coins). Coin processing machines are also being equipped with material sensors to detect counterfeit coins. However, after the issuance of the 500 yen coin, this
It has been revealed that there are foreign coins that are extremely similar to the 500 yen coin (for example, the South Korean 500 won coin).
This foreign coin (500 won) is exactly the same in diameter and material as the 500 yen coin, only the thickness is slightly different.
It is made only 0.2mm thick. If this difference in thickness, that is, the difference in the distance between the sensor and the coin surface, is always maintained correctly, it would be possible to distinguish between the two by increasing the sensitivity of the conventional material sensor, but the coin processing as described above The throughput per unit time of the machine is approximately
The coins move at a very high speed of over 1500 coins/minute, and the coins move at high speed through the coin passage. They often dance upward, and therefore, no matter how much the sensitivity of the material sensor is increased, the output is often the same, making it impossible to reliably distinguish genuine coins from counterfeit coins. Further, no measures have been taken against the fact that the sensitivity of the material sensor changes depending on the temperature.

(Object of the Invention) This invention was made in view of the above-mentioned circumstances, and it is an object of the present invention to provide a coin material sensor that is ideal for a coin processing machine that processes coins in large quantities and at high speed, and that has a temperature guarantee function. It is an object.

(Summary of the Invention) The present invention is a coin material sensor with a temperature compensation function for a high-speed coin processing machine, and in particular a coin material sensor for a coin processing machine that transports coins at high speed by a transport means. It is shaped like a U-shape, and there is a magnet in one of the protrusions of the U-shape, which is excited by an excitation signal.
A secondary coil and one of a differentially wound secondary coil that is electromagnetically induced by the primary coil are provided, and the secondary coil is differentially wound within the U-shaped protrusion of the other side. a regulating member for regulating the movement width of the coin is provided in the recess formed between both the protrusions, and the temperature change rate of the differential output of the secondary coil is set to ΔD, and the secondary coil Let the temperature change rate of either one be △A, and let VAo be the output of the one secondary coil at the reference temperature when there is no coin in the recess between the two protrusions, and when the temperature is T, the coin is Output of one of the secondary coils when conveyed along the recess between the two protrusions
Measure VA and the differential output VD of the secondary coil, and calculate the differential output VDo of the secondary coil with respect to the reference temperature using the following formula: VDo=VD/{1+△D/△A (VA/VAo-1)} The coin material is detected by determining the coin material.

(Embodiment of the Invention) Fig. 1 is a mechanical diagram showing an example of a coin processing machine equipped with a coin material sensor 20 of the present invention. The coins C are sequentially arranged around the periphery by centrifugal force, and the arranged coins C
is delivered to the coin passage 2 outside the rotary disk 1. This coin passage 2 is for sorting and transferring the coins C sent out from the rotary disk 1 according to their outer diameter, and is composed of a fixed member 3 and a movable member 4 arranged in parallel. Shoulders 3A and 4A are formed over the entire length of the fixed member 3 and the movable member 4 on opposing sides, respectively, and the coin C is adapted to move on these shoulders 3A and 4A. . Therefore, coins having a smaller diameter than the opposing distance between the shoulders 3A and 4A will fall from above the coin passage 2. In addition, the movable member 4 is configured to be movable perpendicular to its length direction so as to change the distance from the fixed member 3, and is constantly subjected to force in the enlarged direction, that is, to the right in the figure, by springs 5, 5. There is.
Furthermore, the movable member 4 is provided with a contact part 6 made of a roller, and the circumferential surface of a cam 7 for setting the passage width is in contact with this contact part 6, and the cam 7 is compatible with the largest diameter coin. The cam surfaces 71 to 76 are arranged in the order of cam surface 71, which sets the passage width corresponding to coins with a smaller diameter, to cam surfaces 72, . It is formed into an arcuate surface centered on . A setting dial 10 on which a setting denomination 9 is displayed is attached to the camshaft 8.

On the other hand, the conveyance device 11 is composed of pulleys 12 and 13 arranged at both ends in the length direction of the coin passage 2, and a belt 14 mounted on these pulleys 12 and 13, and includes a drive mechanism such as a motor. (not shown) causes the pulleys 12 and 13 to rotate in the direction of the arrow shown in the figure, and by driving the belt 14 in the same direction, the coin C on the coin passage 2 is conveyed toward the front side in the figure. A coin material sensor 20, which will be described later, is provided in the middle of the conveyance path 2, and a counting sensor 16 consisting of a photoelectric switch or a proximity switch is provided on the front side. The number of coins is counted based on the signal obtained when the position is reached. In addition, a coin material sensor 20 and a counting sensor 16
A coin passage blocking device (not shown) is provided between the coin passageway 2 and the coin passage blocking device (not shown), and when activated, a blocking rod connected to a solenoid projects into the coin passage 2 and blocks the conveyance of the coin C. The activation timing of the blocking rod is when the number of coins to be counted reaches the set value if the number of coins to be counted has been set separately in advance, or when the number of coins to be counted reaches the set value, or when the coin material sensor 2
This is when counterfeit money is detected by 0.

Next, the material sensor 20 of the present invention will be explained with reference to FIGS.
The coin C is conveyed through a recess 23 formed between the protrusions 21, and an excitation coil WE excited by an excitation signal is wound around the protrusion 21. The side coil WA is wound around the protrusion 22, and a similar secondary coil WB is wound around the protrusion 22.
are wound, and the secondary coils WA and WB have the same number of turns but the winding directions are opposite to each other,
The output VD between the output terminal T2 of the secondary winding WA and the output terminal T1 of the secondary winding WB with respect to the common connection point TC is outputted differentially. If the thickness of the coin C is t and the distance between the protrusions 21 and 22 is d, then the coin C is
If the coin C is always conveyed in contact with the upper surface of the protrusion 21 as shown in FIG. However, in the above-mentioned coin processing machine, since the coin C is conveyed at high speed,
As shown in FIG. 2, the object is transported in a dancing state at a distance x from the upper surface of the protrusion 21. As a result of experimentally determining the output between the terminal TC and the terminals T1 and T2 with respect to the dancing distance x during the transportation of the coin C, a characteristic curve as shown in FIG. 3 was obtained. That is, the output VA of the secondary winding WA has a signal level as shown by the △ mark in FIG. 3, and the output VB of the secondary winding WB has a curve like the cross mark in the figure. As a result, the differential output VD (=VA-VB) between the secondary windings WA and WB becomes a curve like the circle mark in FIG. As is clear from this experimental result, the signal level of the differential output VD is approximately
The rate of change is approximately 1% in the AR range of 0.5mm to 2.5mm.
It can be seen that it is only necessary to keep the moving distance x of the coin C during transportation within this range AR. Therefore, in the present invention, as shown in FIG. 4, a regulating member 31 made of ceramic or Bakelite having a thickness x1 is layered on the upper surface of the protrusion 21, and a similar regulating member 31 having a thickness x2 is provided on the lower surface of the protrusion 22. 32 are layered so that the distance x that the coin C moves from the upper surface of the protrusion 21, that is, from the secondary winding WA, ranges from approximately 0.5 mm to 2.5 mm. Therefore, in this example, the thickness of the regulating member 31
x1 is approximately 0.5 mm, and the thickness x2 of the regulating member 32 is the value obtained by subtracting the thickness t of the coin C from the distance d between the protrusions 21 and 22, and subtracting 2.5 mm from that value, that is.
x2 = d-t-2.5, and the regulating members 31 and 32
If set in this way, the range in which the coin C can move will always be in the range of 0.5 mm to 2.5 mm from the top surface of the protrusion 21. In this way, the differential type coin material sensor 20
The regulating members 31 and 32 control the interval at which the coin C passes.
By regulating the change level of the differential output VD and reducing the level of change in the differential output VD, the material of the coin C can be detected stably and accurately.

In addition, although the regulating members 31 and 32 are provided in the above description, they may be molded integrally with the sensor body using Bakelite or ceramic.

Figure 5 shows a comparison of the levels of the differential output VD for various coins. The level of dynamic output VD is decreasing, and the difference between a 500 yen coin and a Korean 500 won is becoming extremely small, but even if coin C moves x, the change in signal level is small, so it is certain that It becomes possible to identify the material.

Therefore, the differential output VD as shown in FIG.
By converting each of the level ranges into digital values and storing them in a memory, it is possible to identify the denomination of the coin by comparing it with the differential signal VD responsive to the material of the coin.

FIG. 6 shows in block form the circuit configuration for identifying coins, in which the differential output VD obtained by the material sensor 20 is input to the comparison circuit 41, and the various coins registered in advance in the memory 40 are input. Outputs a denomination signal MD based on the material by comparing with the level value,
The denomination signal DT set with the setting dial 10 (separately detected by the rotating position of the dial 10) is sent to the denomination discrimination circuit 42, and when it completely matches the denomination signal MD from the comparison circuit 31, the final By outputting a specific denomination signal FD, it becomes possible to identify coins with high accuracy.

In the material sensor described above, when the temperature T of the environment of the coin material sensor 20 changes, the coil impedance changes, the current flowing through the secondary coils WA and WB changes, and the differential output VD also changes. Therefore, it is necessary to calculate the temperature based on the value of the output VA (or VB) of one of the secondary coils when the coin C becomes the recess 23, and compensate the differential output VD to a constant temperature.

Here, the differential output of the secondary coils WA and WB
VD can be approximately expressed as a linear function with a certain rate of change ΔD due to temperature change, and the same can be said of the output VA (or VB) of the secondary coil WA (or WB). Let the rate of change in WA be ΔA. Then, the differential output at the reference temperature To is
If the output of VDo and secondary coil WA is VA ₀ , it can be expressed as VD=VDo{1+ΔD(T-To)}...(1) VA=VAo{1+ΔA(T-To)}...(2) From equations (1) and (2) above, (T-
To) is calculated as T-To=1/ΔA(VA/VAo-1) ......(3), and by substituting equation (3) into equation (1), VD=VDo{1+ΔD/ΔA(VA /VAo−1)} ...(4). The differential output VDo at the reference temperature To is determined from equation (4) as follows: VDo=VD/{1+ΔD/ΔA(VA/VAo−1)} (5).

The differential output VDo expressed by this equation (5) is the differential output of the secondary coils WA and WB at temperature T.
This is the value obtained by converting VD to the value at the reference temperature To. Therefore, the differential output at the reference temperature To
In addition to finding VDo and the output VAo of the secondary coil WA, find the rate of change ΔD of the differential output VD with respect to temperature and the rate of change ΔA of the secondary coil WA (or WB) with respect to temperature. By determining the output VA (or VB) of (or WB), the differential output can always be determined using a value converted to the reference temperature To. Thereby, the material of the above-mentioned object (for example, a coin) can be reliably detected, and the denomination of the coin can be correctly identified.

Note that it is also possible to prepare a table of reference levels for each temperature in advance, measure the temperature T, read out the reference level from the table, and compare it with the detected value VD at that time to detect the material.

(Effects of the Invention) As described above, according to the coin material sensor of the present invention, even if the characteristics of the sensor itself change due to temperature changes, it is possible to always perform detection based on the same standard.

[Brief explanation of drawings]

Fig. 1 is a mechanical diagram showing an example of a coin processing machine to which the present invention is applied, Fig. 2 A and B are diagrams for explaining the operation of the coin material sensor of the present invention, and Fig. 3 is a diagram showing the coin material sensor of the present invention. Figure 4 is a diagram for explaining how the sensor detects the sensor, Figure 4 is a diagram showing an example of the structure of the coin material sensor of the present invention, and Figure 5 is a comparison of signals obtained by the coin material sensor of the present invention for each denomination. FIG. 6 is a circuit diagram of a coin identification device using the present invention. 1...Rotary disk, 2...Coin passage, 3...Fixing member, 4
...Movable member, 5...Spring, 7...Cam, 11...Transport device, 20...Coin material sensor, 21, 22...Protrusion,
31, 32...Regulating member, C...Coin.

Claims (1)

[Scope of Claims] 1. A coin material sensor for a coin processing machine that conveys coins at high speed by a conveyance means, which has a U-shaped cross section and has an excitation signal in one protrusion of the U-shape. A primary coil is excited by the coil, and a secondary coil is wound in a differential manner and is electromagnetically induced by the primary coil. A regulating member for regulating the movement width of the coin is provided in the recess formed between the two protrusions, and the temperature change rate of the differential output of the secondary coil is set to ΔD, Let the temperature change rate of one of the secondary coils be ΔA, and let VAo be the output of the one secondary coil at the reference temperature when there is no coin in the recess between the two protrusions, and when the temperature is T. When a coin is conveyed along the recess between both U-shaped protrusions, the output VA of the one secondary coil and the differential output VD of the secondary coil are measured, and VDo=VD/{1+ΔD/ ΔA(VA/VAo−1)} For a high-speed coin processing machine, the coin material is detected by determining the differential output VDo of the secondary coil with respect to the reference temperature using the following formula. Coin material sensor with temperature compensation function.