FR2580098A1 - - Google Patents

Abstract

THE INVENTION RELATES TO LOW ENERGY CONSUMPTION COINS DISCRIMINATION APPARATUS. IT INCLUDES A MICROPROCESSOR 20 WHICH GOES RAPIDLY FROM A SLEEPING STATE TO A WAKE-UP STATE, FOLLOWING THE CLOSING OF A SWITCH 44, THE SAME RESULTING FROM THE INSERTION OF A PART 12 IN THE APPARATUS 10 MEANS INCLUDING A PIEZOELECTRIC ELEMENT 14 WITH AMPLIFIER AND INTEGRATOR CIRCUIT 16, AN ANALOGENUMERIC CONVERTER 18 AND THE MICROPROCESSOR 20 DETECT THE PRESENCE AND EARTH OF A PIECE 12. OPTICAL DETECTION MEANS OF ITS APRES DETERMINED THE PIECE INTO THE SURFACE. CONTACT WITH THE PIEZOELECTRIC ELEMENT 14. FIELD OF APPLICATION; PARCMETERS, AUTOMATIC DISTRIBUTORS, PUBLIC TELEPHONES, ETC.

Description

The invention relates to a low power device for detecting the

validity and value of a

piece of money.

  There seems to be a great need for coin discriminators, of weak

  to use in devices such as

  meters, telephone booths and vending machines. Most coin discrimination apparatus of the prior art tend to be

  mechanical nature. We only know a few

  electronic devices of medium reliability. Since most prior electronic devices are placed near an energy source, the problem of

  energy consumption has never been a concern

  important cup. However, there are some

  such as parking areas> where

  does not have external energy. It was therefore necessary

  to look for a low power, high precision and robustness device. Since no

  device does not seem to fit this description.

  it was necessary to invent one.

  The use of piezoelectric elements is

  not common in the area of discrimination of

  these money. However, the United States patent

  No. 3,776,338 discloses a piezoelectric detector used for the detection of the presence of a coin. The use of a rudimentary skating pad to cover the surface of a piezoelectric element is

  also indicated. Another description of the use

  of piezoelectric elements is given in an article entitled "Poly (vinylidene) Fluoride Used For Piezo Electric Coin Sensors". This article was written by G.R.Crane de

  Bell Labs, and appeared in volume SU 25, N 6 (No.

  December 1978) of IEEE Transactions on Sonics and Ultraso-

nics, pages 393-395.

  Certain references of the prior art disclose

  wind systems that use two or more steps to detect coins. For example, U.S. Patent No. 4,082,099 discloses a two-step process for the discrimination of coins. The first step is the detection of the part by means of a metal-sensitive sensor. The second step uses photoelectric elements. Similarly, U.S. Patent No. 4,436,196 discloses a

  another two-part test and also indicates the use of

  of a light-emitting diode and a micro-

  processor. Similarly, U.S. Patent No. 3,211,267 discloses a two-part test for determining the weight and diameter of the workpiece.

change.

  A number of previous references

  describe the use of other photoelectric devices

  to detect presence / or surfaces and / or

  diameters of coins. We can note in particular

  No. 3,378,962, 4,249,648, 4,267,916 and 4,474,281 disclose the use of light emitting diode arrays for detecting coin parameters such as speed, surface, diameter, etc. Other interesting patents

  aspects of photo-detection

  of the present invention are the United States patents

  United States of America Nos. 3,939,954, 4,436,103 and 4,442,850.

  seems that none of the previous references quoted above

  known until now, do not describe the same structure

  same function or function as described in this Memorandum. Briefly described, the invention relates to a low power apparatus for discrimination of

  coins, intended for use in parking lots

  meters, telephone booths,

  similar devices and devices. The coin discriminator includes a piezoelectric transducer for measuring the mass of the coin and a photoelectric sensor for detecting the surface of the coin. The circuit starts in dormant state, at low power. A coin is initially inserted into the counter. The movement of a workpiece transfer handle activates a limit switch that generates an awakening pulse. The movement of the handle also forces the room to enter a chute making it

  fall on the piezoelectric transducer. A knee pad

  cellular thanne covers the piezoelectric element and serves to damp the oscillations caused by the impact of the piece. If a large enough pulse is produced by the impact on the piezoelectric transducer, an infrared light emitting diode present in the photoelectric detection portion of the circuit is illuminated by

  a control microprocessor. The photodetect part

  circuit advantageously comprises a photo-diode

  illuminated by the infrared light emitting diode.

  A microprocessor circuit digitally samples the output signal of the photodiode to determine the minimum illumination (at the maximum eclipse point) which itself represents the net area of the workpiece. The photo-sensor can therefore discriminate between coins, invalid, which have holes, and valid coins of the same diameter. The signal

  produced by the impact of the part on the piezo transducer

  electrical power is integrated and sampled by the micro-

  processor so that the mass of the part is determined.

  The microprocessor first uses the information produced by the photoelectric sensor to determine if the part is within acceptable surface limits. If the room

  passes the photo sensor test, the mass information pro-

  coming from the piezoelectric transducer is then also

  compared to the corresponding limits during an audit.

  double precision cation. The discriminator automatically returns

  to a dormant state once it has completed the process of discrimination. The invention is advantageously used in a parking meter; however, it can also be used in other environments, such as cabins

  telephone and vending machines.

  The invention will be described in more detail with reference to the accompanying drawings by way of non-limiting examples and in which: FIG. 1 is a simplified diagram of the preferred embodiment of the invention; Figure 2 is a detailed diagram of the preferred embodiment of the invention illustrated in Figure 1; Fig. 3 is a cross section of the coin chute showing how the coin strikes the piezoelectric transducer; 20. Figure 4A is a diagram illustrating the photoelectric system for measuring the surface of a workpiece; Fig. 4B is a diagram illustrating how the piece eclipses the optical system shown in Fig. 4A; Figure 5A illustrates the waveforms of

  two different signals-produced when different pieces of

  they strike the piezoelectric element; Fig. 5B is a graph showing the integration curves of the signals of Fig. 5A for two different coin values; Fig. 5C is a graph showing the output signal of the photoelectric detection system

  of parts of Figures 4A and 4B for two values.

  their different parts; Figure 6A is a front view of an assembled parking meter using the present invention;

  FIG. 6B is a front view of the park.

  meter of Figure 6A whose hood is removed; Figure 6C is an elevation of the left side of the parking meter shown in Figure 6B; Fig. 6D is a top plan view of the entire parking meter shown in Fig. 6B; Figure 6E is an elevation of one of the runway plates defining the coin chute; Fig. 6F is a perspective view of the coin input transfer block; 15. Figure 6G is a perspective view of a coin entry frame member; Fig. 6H is a front view of a liquid crystal display indicator assembly; Fig. 6I is an elevation of the liquid crystal display indicator assembly of Fig. 6H;

  FIG. 6J is an exploded perspective view

  tee of the boot assembly and coin transfer lever.

  Figure 6K is an exploded view showing

  how the meter's box receives the electronic modules

interchangeable

  Figure 7A is a perspective view of

  application of the invention to a telephone

lunch; and

  30. Figure 7B is a perspective view of

  application of the invention to a vending machine

matic.

  In the description which follows, the same references

  numerical references are used to identify the same

  elements on the different views and figures that illustrate

the invention.

  FIG. 1 represents, in schematic form,

  Simplified diagram, the preferred embodiment of the apparatus 10 according to the invention, and Figures 3 to 6K show the structure. Initially, the circuit

  is in a dormant state, at low power. A useful

  The user triggers the counter by inserting a coin 12 into a slot 81 and then manipulating a coin.

  handle 98 to the right so that a block 96 of trans-

  pieces of equipment come knocking on and

  switch 34 awake the end-of-travel type. At the same time, the part 12 is moved by a box 102 towards the edge of a base 114 of an element 80

  parts, so that it falls into a chute 52.

  wake-up switch 44 makes the circuit go into a state

  pre-active, at low power, for a maximum of about 500 milli-

  seconds. During the pre-active period of 500 millisecon-

  of, the microprocessor is preconditioned to search for a signal from the piezoelectric transducer 16. In addition, the internal clock 33, with a frequency of 32.768 kHz,

  controlled by a crystal 34, is automatically disconnected-

  and replaced by a faster, but less accurate, 400 kHz clock. The clock frequency of 400 kHz is established by the resistor and capacitor network 40 and 42 which corresponds to the resistor R11 and the capacitor C4 in FIG. 2. The impact of the part 12 on the piezoelectric element 14 causes the lighting the light-emitting diode D4 of the driving circuit 26 in advance of the piece 12. If no coin comes into contact

  with the piezoelectric transducer 14 at the end 500 milli-

  seconds, the circuit then automatically returns to the

  Pos. The output of the piezoelectric transducer 14 is integrated by an amplifier and integrator circuit 16

  and is applied as an input signal to a conver-

  analog / digital weaver 18 whose output is connected

  to a microprocessor 20. A light-emitting diode circuit 26

  minescente illuminates a photo-sensor 28 that produces a

  an output signal which is amplified by an amplifying circuit

  30, and applied as a second input to the analog-to-digital converter circuit 18. Activation of the piezoelectric transducer 14 produces an enable signal which is applied to a voltage regulator 22, causing the voltage VCB to jump off. a low voltage value VB at a higher value VC (5 volts) which is sufficient to control the light emitting diode D4. The regulator 22 also sends a "battery" signal

  "to the microprocessor 20 to indicate, where appropriate,

  ant, that the power source is weakened.

  The chute 52 with parts is made so

  that the piece 12 passes between the circuit 26 with an electronic diode

  luminescent and the photo-sensor 28 after striking on the piezoelectric transducer 14. The microcomputer 20

  samples the output signal of the analog converter

  number 18 at very short intervals in order to deter-

  undermine when a piece 12 has reached an eclipse position

  maximum of the light between the diode circuit 26

  luminescent and the circuit 28 to photo-sensor.

  A coin identification memory and time programming circuit 32 is programmed to assist the microprocessor 20 in identifying a coin

  12 of unknown value. The output signal of the micropro-

  crier 20 is applied as input to a circuit 36

  LCD display which, in turn,

  of the visual or LCD VIS and IND indicators of a circuit 38. The circuit 10 can

  initialized by a manual maneuver of an interrup-

  time reset 46.

  Figure 2 is a detailed schematic view

  of the preferred embodiment of the invention

  all the important details of the circuit.

  One can also refer to the following list of parts which gives other indications concerning the values and the origin of the electrical components:

LIST OF PIECES

A. INTEGRATED CIRCUITS

  Part Number Manufacturer Description

  part U1 ITLC27M4AIM Texas Instruments Operational kApli U2 TLC541IN Texas Instruments A / D Converter U3 X2443PI Xicor NOVRAM U4 CCP324CN National Semicon- Microprocessor ductor U7 MM5483N National SemiconAttachment visual CL ductor U9 RV4193NB Raytheon Regulator

B. CAPACITORS

n of compo- Description

  C1 100 pF; polystyrene; + 2.5% C2 O, IgF; Mono CD decoupling C3 100 pF3DM Mica, 5% C4 0.047 uF; Poly, +5% C50, LiF-Mono CD, C6 82pF decoupling. DM Mica, 5% C 470 pF; DM Mica; 5% C8 50 pF; DM Mica; 5% C9 50 pF; DM Mica; 5% C10O 470gF, 6.3 V; electrolytic C1l 56pF; DM Mica; 5%

C. RESISTORS

n of compo- Description

  R1 2.4 MA, 5%; 1 / 4W; Carbon R2 10 kΩ; 5%; 1 / 4W; Carbon

n of compo- Description

  R3 20 MaC. 5%; 1 / 4W; Carbon R4 10X.!. 5%; 1 / 4W; Carbon J R5 10 kQ. . 1%; RN55D; MF type R6 40 k. 1%; RM55D, MF type R7 1 MD .. 5%; 1 / 4W; Carbon R8 180-. 5%; 1 / 4W; Carbon R9 4.7kL, 5%; 1 / 4W; Carbon R10 4, 7kU. 5%; 1 / 4W; Carbon R11 1 MQ%; 5%; 1 / 4W; R12 Carbon 15k-Q., 5%; 1 / 4W; Carbon R13 1 M-: 5% -; 1 / 4W; Carbon R14 220 kf. 5%; 1 / 4W; Carbon i5 R15 20 MQ. 5%; 1/4 W; Carbon R16 4.7kQ-; 5%; 1/4 W; Carbon R17 360 kL, 5%; 1/4 W; Carbon R18 51.1 ka. 1%; RN55D; MF type R19 16.9 I 1%; RN55D; MF type

D. OTHER BUSINESS

n of Description com- pon

  part L1 300 MH Inductance, 1/4 W, molded type

  CR1 CXIV-32. Satek Inc., 32.768 kHz; crystals

  768 kHz tal D1 IN914 (1N4148) Diode D2 HSCH 1001 Diode D3 HSCH 1001 Diode D4 LD242-2 LED, Siemens D5 SFH206 Photodiode, Siemens Qi 2N3906 Transistor Q2 2N3906 Transistor Q3 2N4401 Transistor

  Xi 16500-5A Piezo ceramic disc

cudgel

n of Description com- pon

  part _ B1, B2, B3 MN1500 DURACELL alkaline battery

(-29 C to + 70 C)

  or B4, B5 BR-2 / 3A-1P Lithium battery, PANASONIC

<(-40 C to + 85 C)

  LCD1 Excelix 4320- Excel Technology, Visual 4 RPQ-O Digit LCD2 Excel Indicator Technology, Visual CL Excelix On Demand LCD3 Excel Indicator Technology, Visual CL Excelix On Demand Figure 3 shows the progression of a coin in the chute 48 to pieces. After the piece has been inserted into the slot 81, it falls along the chute 52 and strikes a urethane-type shock absorbing material 50. The impact of the piece 12 is damped by the shock absorbing material 50 and is transmitted to the piezoelectric transducer 14. The shock absorption material 50 is advantageously constituted by a cellular urethane such as the "PORON N 4701" type. ", produced by Rogers Corporation. The signal produced by the piezoelectric transducer 14 is integrated by the circuit 10 of FIG. 1, which produces an output signal proportional to the mass of the part 12. By accurately controlling the fall of the part 12 over a given irremovable distance, it is possible to obtain precisely

  repetitive results. As a result, a 12 piece

  in chute 52 always produces the same impulse - -

  or the same impact on the piezoelectric transducer 14. The integrated signal from the pulse therefore always gives the same result representative of the mass of the

  piece. The piezoelectric transducer 14 is advantageously

  placed at a certain angle to

  the fall of the room 12 to allow the latter

re going on the track.

  The output signal of the piezoelectric transducer

  that is illustrated by curves 67 and 68 in the graph of Figure 5A. Curve 67 is directly proportional to the pulse generated by a 12 cent coin 12

  striking the PVC type shock absorbing material 50.

  In the absence of the material 50, the curve 67 of the pulse would not be so regular. After the piece 12 has moved away, the curve 67 returns to a straight line. Waveform 68 represents the impact of a 25-cent coin 12 for comparison purposes. The peak voltage pulse generated by the impact of a 12 cent coin is about 8 volts. The 8-volt signal produced by the transducer 14 represents the pulse, that is, the live force of the 25-cent coin. The

  signal 67 or 68 is applied to the input of the integrated circuit.

  16 formed by the operational amplifier U1, the resistor R4 and the capacitor C1. The output signal of the amplifier and integrator circuit 16 is presented under

  waveforms 70 and 72 of the graph of FIG. 5B.

  The waveform 70 is the integrated output signal of the

  impulse caused by the fall of a coin of 25 cents.

  Waveform 72 is the integrated output signal of

  the impulse obtained by the fall of a piece 12 of 10 cents.

  Since the integrated signal of the pulse, that is,

  say the live force of a piece, is proportional to the

  mass, so it is clear that the curves 70 and 72

  particularly risk the masses of pieces 12 of

  25 cents and 10 cents respectively.

  The analog / digital converter 18

  the waveforms 70 and 72 of the amplification circuit

  and integrator 16 every 100 microseconds under the control of microcomputer 20, and it records in memory

  the peak voltage {P). If the peak or peak voltage

  P exceeds a minimum threshold, indicating a room capable of

  Before being valid, the microcomputer 20 prepares to

  turn on the light-emitting diode circuit 26.

  However, before actually turning on the light emitting diode

  D4, the circuit 20 of the micro-calculator exchanging

  the output signal of the photodetector-amplifier

  30 and stores this value in memory as voltage Vo. The microcomputer 20 then passes the current in the light emitting diode D4 infrared

  and starts to sample the output voltage of the photo-

  D5 detector as amplified by the amplifier circuit.

30.

  After the piece 12 has crossed the piezoelectric transducer 14, it continues to descend by rolling along the chute 52 to near the zone 54

  optical trajectory. Figure 4A represents schematic

  only the part 12 to its passage through the zone 54 optical surface measurement. The light-emitting diode

  D4 produces a beam 56 of infrared light that illuminates

  A collimated lens 58 shines through the path of the workpiece 12. The light 60 that is not eclipsed by a workpiece 12 arrives on a converging lens 62 that produces a convergent infrared beam 64 which , himself, arrives on the

  photo diode D5; The central axis 66 indicates the alignment

  the elements and the room 12.

  Figure 4B illustrates transversely, in

  details, how room 12 eclipses the light beam

  collimnated 60. Exhibit 12 in the center o of Figure 4B is

  represented in the maximum eclipse position of the

  collimated infrared water 60. At this point, the quantity

  maximum of 60 light is stopped by the piece 12 and the

  minimum amount of light 64 is received by the photo-

  diode D5. The output signal of the photodiode D5 is

  sampled at very short intervals by the micro-process-

  20 to determine the signal point

  minimum output that corresponds to the point of eclipse

  ximal, by the workpiece, collimated beam 60. Figure 5C shows two typical waveforms 74 and 76 of optical origin. The waveform 74 corresponds to the voltage signal produced by the passage of the coin 12 by 25 cents, whereas the waveform 76 represents

  the signal produced by the passage of a room 12 of 10 -

  cents. Since 25 cent coin is larger than 10 cent coin, it's obvious that 25 cents

  the light as the 10 cent coin 12 which is smaller.

  As a result, the peak or peak of the waveform 74 associated with the 25-cent coin is more pronounced than that of the waveform 76 associated with the 10-cent coin, since the waveform 74 represents the eclipse more light and, therefore, produces a greater aroma voltage variation at the output of the amplifier circuit 30. The output of the circuit 30 is also sampled by the analog / digital converter circuit 18 under the control of

  microcomputer circuit 20 which records the voltage

  ximal Vp and the minimum voltage VM in memory. The mic-

  calculator 20 then calculates the following ratio:

VM - V0

A =

V - V

  The ratio A represents the area of the surface of the part 12 and it does not vary when the intensity of the light-emitting diode D4, the offset current of

  the photodiode or the speed of the piece 12 varies with

  wise in the lens system 58 and 60. The report A

  and the peak output voltage P of the piezoelectric circuit

  amplifier and integrator are compared to the acceptable range of values recorded in the circuit.

  32 of parts identification and programming memory.

  time. If a concordance appears in tolerances

  of reasonably small values, Exhibit 12

  is identified and accepted as valid. If no concordance

  dance is found, the piece is identified as being

  invalid or invalid. In the preferred form of reali-

  According to the invention, the piece 12, whether valid or not, falls into a coin-operated boot. However, in other embodiments, the invalid coin could be

  rejected and returned to the user.

  The microcomputer 20 and the electronic circuit

  that associated are normally in the dormant state, during which the device 10 requires a minimum current VB at the

  battery or battery. The voltage VB is sufficient to control

  der the visual 38 LCDs and indicators but

  insufficient to control the light-emitting diode D4.

  In the dormant state, the microcomputer 20 is driven by the crystal-controlled clock 34 at a frequency of 32.768 kHz. The frequency of 32.768 kHz is subjected to an internal division of the microcomputer 20, so as to produce precision synchronization pulses for the internal circuit. In the dormant state, the time remaining on the counter is displayed by the circuit 38, the details of which are illustrated in FIGS. 6H and 6I. The digital output signal of the apparatus 10 is updated

  every minute until the expiration of time, such a shell

  mined by the number of coins inserted into the meter

  10. A red liquid crystal indicator 120 is exci-

  to indicate a "time expired" situation. The indication

  yellow indicator 122 is advantageously used as

  time passing on some meters to indicate that the device 10 has counted down to zero time on the counter. The red flag 120 is then used to indicate the end time limit limit (for example -2 hours). The preferred embodiment is capable of counting down to -9 hours 59 minutes. In counters with no possibility of time exceeding, the yellow indicator 122 is presented instantaneously only at the passage of direction 10 by zero minutes, then the red indicator 120 is displayed and the visual

  124 liquid crystal counts time in negative numbers

  tive. This procedure is typical of the use of

  invention in the United States of America. However, in

In other countries such as Great Britain, it is expected that the yellow flag 122 is presented between the meter's zero time and the timeout limit. Once this limit is reached, the red flag 120 is presented, indicating a more serious offense. Since the device 10 is capable of measuring up to -9 hours and 59 minutes of timeout using the liquid crystal display panel 124, it would be possible to

  issue parking tickets carrying a sum of

  exactly proportional to the actual amplitude of the

time.

  The inner and outer mechanical parts of the invention are shown in detail in the figures

  6A and 6I. A parking meter housing 70 encloses the whole -

  mechanical and electrical elements. An organ 8C of

  of coins is the first element m4-

  The slot 81 for parts communicates with the chute 52 to pieces (as shown in Figure 3). The chute 52 is formed of two symmetrical omgianes 82 of frame. The bodies 82 of casting are realized

  from 85 and 87. outer profile parts, Kne

  the opening 84 in the frame elements 82 is posi-

  The latter comprises two zones, namely: zone 52 of the piezoelectric transducer and zone 54 of the photo-sensor. An inner housing 86 for the photodiode portion 28 and another inner housing 88 for the electro-luminescent diode electronic portion 26 are disposed on either side of the aperture 84 to scan the path of the workpiece 12 while It goes down along the zone of the photosensor of the chute 54. A holding bracket 94 is placed upstream of the opening 84 and is arranged to receive the piezoelectric transducer 14 and the urethane impact pad. tubular. A track damper 93 shown in FIG. 6C is used to minimize bounce and jump of the workpiece as it rolls down along the chute 52 and 54. A bracket for supporting the piezoelectric transducer 14 and the pad

  is attached to the main frame 97. A

  The flat sole 95 is also attached to the main frame 97 and serves to support a conventional rate card. The latter is not illustrated because it is of no help for understanding the invention. A return spring 99 is connected to the part translation box 90,

  and returns a flange 109 to its rest position. The res-

  fate 99 also serves to maintain the translation box 90

  remote from wake-up end switch 44

  unless the translational handle 98 has been manipulated

  EEA. A bracket 101 attached to the main frame 97 is used to support the profiled paths 85 and 87. A bracket 18 circuit board fixed circuit board 107 on the back of the device. The wafer 107 carries most of the active elements of the apparatus 10, according to

  the invention, including the microprocessor 20. The

  LCD panel 38 is connected to

  the apparatus by means of a spacer 105.

  A molded part entry transfer block 96 is shown in detail in FIG. 6F. The transfer block 96 comprises a handle 98, a flange 109, a projection 100 and two plates forming a box-like portion 102 for the translation of the workpiece 12. The flange 109 serves to close the chute after a workpiece has been cut. been inserted while it is being translated there. The translational portion 102 begins to lower the piece 12 on the chute 52 in response to a maneuver of

the handle 98.

  The part entry frame member 80 is

  felt in more detail in Figure 6G. A handle slot 106 is adapted to receive projection 100 of block 66

  parts transfer. A movement of block 96 of trans-

  Filling of the pieces along the length of the slot 106 causes a displacement of the translation box 102 of the entrance slot 81 towards the point where it releases the piece so that it descends along the chute 52. part entry includes a weather protection cap 108, which subtracts the coin slot 81 and the translational handle 98 from the effects of rain,

  snow and other elements. The tapered base 114 of ..

  the input member 80 is configured to center the workpiece

  12 before it falls into chute 52. There are openings

  112 forming a grid in the base 114 allows

  attempt to moisture to pass through the input organ 80

  without damaging chute 52. It also serves to improve

  improve the resistance proposed by the apparatus 10 according to

  the invention of vandals who could use liquid

  to block by erasing the internal mechanisms, and prevent access to the area of the measuring wires of parts etc. In summary, the preferred embodiment of the meter according to the invention operates in a manner which will now be described. Initially, it is assumed that no time is displayed on the counter and that, therefore, the counter is initially in the low power dormant state. Under these conditions, the red indicator 120 is illuminated. Starting with the assumptions given above, the user of the meter first introduces a Iece 12 into the coin entry slot 81. The piece 12 is then kept captive by the translation box 102 of

  parts forming part of the transfer block 96. Then the use

  counter reader pushes on the transfer handle 96,

  along the slot 106, which has the effect of

  ber the piece 12 of the rim formed by the tapered base 114 and begin its descent along the chute 52.

  The operation of the handle 98 also causes the actuation

  By the transfer block, the wake-up switch 44 makes the circuit 10 from its low-power dormant state to its pre-active state. In the pre-active state, the microprocessor 20 goes from the low frequency 32.768 kHz clock 33 to the frequency plus

  high, equal to 400 kHz of the clock 35. The circuit 10

  it is in the pre-active state for 500 milliseconds and returns to the dormant state unless a signal is produced by the piezoelectric transducer 14. The coin 12 strikes

  then on the PVC impact pad 50 which covers the trans-

  Piezoelectric Driver 14. The impact of the workpiece 12 on the piezoelectric transducer 14 provides pulses having waveforms similar to the curves 67 and 68 as shown in FIG. 5A. The waveforms 67 and 68 of the pulses are integrated by the amplifier circuit

  and integrator 16 and sampled by the conver-

  The maximum value of the integrated waveform (such as 70 and 72 of FIG. B) is stored in memory by the microcomputer 20 as a voltage P. The integrated signal produced by the impact of the piece 12 on the piezoelectric transducer 14 is directly proportional to the mass of the niece. Yes

  the voltage P is greater than a minimum threshold, the micro-

  calculator places the circuit in its state totally

  active. The coin then crosses the light beam colli-

  60, which causes the production of an output signal similar to the waveforms 74 and 76 of Fig. C. The recesses of the optical waveforms 74 and 76 represent

  feel the net area in cross section of the room.

  Therefore, the piece, such as a dime, presenting a

  hole would produce a waveform different from that

  duit by a dime without hole. The output signal of the photodiode D5 of the detector 28 is sampled by the analog / digital converter 18 and this minimum is

  also recorded by the calculator 20. The value

  registered minimum is converted by an A report previously described as follows:

V - V

V - V

P 0

  The ratio A of surface of light, characterized

  of the net area in section of room 12, is

  equipped with acceptable reports A recorded in the coin identification memory circuit 32 and time program. If the ratio A is unacceptable, the part is rejected, either by being directed to the box

  parts, either by being towards a discharge chute. How-

  If the ratio A is acceptable, the microcomputer then compares the signal P representative of the maximum excursion of the integrated waveform 70 or 72 shown in Figure 5B. If the integrated signal P is included in the

  acceptable limits recorded in unit 32 of memo-

  In the case of coin identification and time programming, piece 32 is finally considered valid and advanced to the coin box. If the part does not pass the integrated signal test, it is either advanced to the coin boot and held, or advanced to the coin reject chute and returned to the meter user. If it is assumed that the part 12 has passed both the surface ratio test A and the integrated signal test P, the microprocessor 20 then controls the driver circuit 36 of the liquid crystal display so that the 124 LCD Part Displays

  in digital form the time we have on the counter.

  The introduction of other pieces 12 valid in the device 10 causes the recording by the microcomputer 20, a longer time displayed on the LCD 124. When the counter 10 counts the time under the control of the second clock 35, which operates at the frequency of 32.768 kHz, the time shown on the display 124 decreases. If the visual reaches a certain minimal point,

  by Eemple zero, the yellow indicator 122 can be actuated.

  At the moment the counter continues to count down the time beyond zero, the red indicator 120 is actuated when

  the overflow limit is reached. The device

  is able to follow a time

  9 hours and 59 minutes. On average, it takes about 300 milliseconds between the moment the piece 12 strikes the piezoelectric transducer 14 and the instant when the circuit

returns in its dormant state.

  The preferred embodiment of the apparatus according to the invention is intended to be used in a parking meter. Cepêndant, the fundamental discriminator of

  parts could also be used in other applications.

  cations. It should be noted, for example, the use of the coin discriminator in a public telephone 126

  as shown in Figure 7A. Alternatively, discrimination

  parts can be used in a dispenser

  conventional automatic 128 as shown in FIG. 7B.

  The discriminator 10 of parts just described in detail has several important advantages over the prior art. First, it uses a small amount of energy because it is in the active state, at high power, only for a short period of time. Then, by removing a large number of mechanical parts associated with conventional parking meters and the like, it is possible to significantly increase the reliability of the parking meter, due to the fact that the number of wear parts is lower. Thirdly, since many of the parts are made of electronic components that can be integrated, it is possible to achieve substantial cost reductions due to

  increased savings in sizing. Quatriè-

  The device is very precise because it is controlled by a very reliable reference frequency. Finally, fifthly the device is able to discriminate very accurately between valid parts and invalid parts. The power to discriminate against coins seems to be significantly higher than that of

  classical mechanical coin discriminators.

  Certain features of the invention may

  can be modified without departing from its scope. For example, although the preferred embodiment of the apparatus according to the invention provides for the realization of a wake-up switch 44 to move the device from the dormant state to the active state, it is possible that

  switch 44 is eliminated and the pulse signal

  The output generated by the piezoelectric element 14 is used as the waking signal. In other words, the pulse signal produced by the workpiece 12 could assume the two functions of awakening the microprocessor 20 and providing an electrical measurement of the wattage. impact of the workpiece in the piezoelectric element 14, as well as to turn on the light-emitting diode D4. The apparatus 10 according to the invention can also be associated with a coin rejection chute which works in the usual manner by returning

  a piece not accepted to the user of the meter.

  It goes without saying that many modifications can be made to the apparatus described and shown

  without departing from the scope of the invention.

Claims (27)

REVENDI CATI ONS   A coin discriminating apparatus (12), characterized in that it comprises falling means (52) dropping a coin over a predetermined distance, piezoelectric means (14) for receiving the impact of the coin. piece after falling over said predetermined distance and means (16, 18, 20) of   mass detection of the room, linked to   electrical devices to determine the mass of the piece   according to the impact of the latter on the said piezo electric.   2. Apparatus according to claim 1, characterized   in that it comprises means (54) for detecting   surface tick to determine the surface of the   piece after coming into contact with the piezo electric.   3. Apparatus according to claim 2, characterized   it includes in addition a first source   power supply for applying a voltage   when the latter is in a dormant state, a second power supply source for applying a voltage VA to the apparatus when it is in an active state, and means (22) for circuit powering which, in response to the presence of said piece in the apparatus, pass it into a state   active by applying a VA voltage to it in response to the   troduction of the piece in said apparatus, the tension   active VA being higher than the dormant voltage VD-   4. Apparatus according to claim 3, characterized   in that the optical surface detection means comprise optical scanning means (D5) for   scan the room and produce a proportional output signal   on the surface of the room, and micro-   processor f20) connected to the scanning optical means for digitally sampling the output signal of the optical scanning means and recording a value proportional to the maximum excursion of the signal when said part is scanned by said scanning means. An apparatus according to claim 4, characterized in that the mass-detecting means of the workpiece comprises integrating means (16) for integrating the output signal of the piezoelectric means and producing a signal proportional to the mass of the room   Apparatus according to claim 5, characterized   in that it further comprises means (50) for absorbing   the shock of the workpiece, intended to be in contact with the piezoelectric means and to absorb a certain part of the shock of the workpiece when it falls on said piezoelectric means.   Apparatus according to claim 6, characterized   in that it further comprises a switch (44) in response to   to the insertion of a coin into the apparatus, to produce a wake-up signal for placing the microprocessor means in a ready state, Apparatus according to claim 6, characterized   in that the impact of a part on the piezoelectric means   produces a wake-up signal intended to place in a   pre-active state said microprocessor means.   Apparatus according to claim 6, characterized   in that it further comprises a first clock (33) for supplying clock pulses to the microprocessor means when the apparatus is in said state sleeping.   Apparatus according to claim 9, characterized   in that it further comprises a second clock (35) for supplying clock pulses to said microprocessor means when the apparatus is in the pre-active state and in the active state, the frequency of the second clock being greater than the frequency of the first clock.   Apparatus according to claim 10, characterized   in that it also includes a converter   logic / digital (18) controlled by the micro-means   processor for sampling the output signals of the mass detection means of the workpiece and the optical surface detection means and for transmitting this   information to microprocessor means.   Apparatus according to claim 11, characterized   in that it further comprises a memory (32) connected   to the microprocessor means in order to record a   information regarding the identification of valid parts.   Apparatus according to claim 12, characterized   in that it also includes means (38) for displaying   liquid crystal display for producing a visual output representative of the identification of a valid coin.   Apparatus according to claim 1, characterized   risé in that it is incorporated in a parking meter (10) .-   15. Apparatus according to claim 1, characterized   because it is associated with an automatic dispenser   that (128) intended for the sale of articles in response to lan. detection of valid parts.   Apparatus according to claim 1, characterized   in that it is connected to a telephone (126) to provide telephone services in response to the detection of valid parts.   17. Coin discriminating apparatus (12), characterized in that it comprises piezoelectric means (14) intended to receive the impact of a coin, detection means (16, 18, 20) mass of room   connected to the piezoelectric means in order to determine   the mass of the workpiece after the impact thereof on the piezoelectric means, said detection means   of a part comprising integration means (16) for   to integrate the output signal from the piezo-   electrically generating an output signal proportional to the mass of the workpiece, the apparatus further comprising surface optical sensing means (54) for determining the surface of the workpiece after it comes into contact with the piezoelectric means, the surface detection means comprising optical scanning means (D51) for scanning the workpiece and producing an output signal proportional to the surface of said workpiece, and microprocessor means (20) connected to said workpiece detection means; the piece and the surface optical detection means, in order to compare the output signals   of these detection means to predetermined ranges of values.   finished mass and surface pieces to determine if these parts are valid,   Apparatus according to claim 17, characterized   in that it further comprises first power supply means for supplying a voltage VD to the apparatus when the latter is in a dormant state, with low energy consumption, second means (18,22 ) to supply a voltage VA to the apparatus when the apparatus is in an active part discriminating state, the voltage VA being greater than the voltage VD, and means for detecting the presence of the workpiece in the device before   scanning the room by said optimal scanning means   that to apply said voltage VA to the apparatus and to   remove the VD voltage from the device.   Coin discriminating apparatus (12), characterized in that it comprises piezoelectric means (14) for receiving the impact of a coin, means (16, 18, 20) for detecting the coin mass of a part connected to the piezoelectric means to determine the mass of the part according to the impact thereof on the piezoelectric means, the means   mass detection system comprising means for integrating   (16) for integrating the output signal of the piezoelectric means and producing a voltage of   output P proportional to the mass of the room, this   also comprising optical surface detection means (54) for determining the surface of the   piece after coming into contact with the piezo   electrical means, the optical surface detection means comprising optical scanning means (D5) for scanning said workpiece and producing an output signal Vp proportional to the surface of the workpiece and microprocessor means (20) connected to the workpiece means; optical surface detection and mass detection means of the workpiece to produce a characteristic report A of a workpiece, such as: VM VO A = V -V   p o VO is the voltage of the optical surface detection means before they are activated,   VM is the minimum output voltage of the detection means   after being switched on, and Vp is the absolute maximum output voltage of the surface optical detection means as a result of the passage of the workpiece, the microprocessor means comparing the value of the ratio A and the output value P to beaches of   representative values of valid coins, in order to determine undermine if said piece is valid.   20. Discriminating coin apparatus (12) characterized in that it comprises coin receiving means having a slot (81) for receiving a coin, means (90) for translating coins.   parts intended to move the part of the means of reception   a chute (52) for receiving the workpiece of the drop zone and for causing it to fall by a predetermined distance, piezoelectric means (14) placed in said chute to receive the falling zone of the workpiece; impact of the piece after falling on   said predetermined distance, and means for integrating   (16) connected to the piezoelectric means in order to inte-   manage the output signal of these piezoelectric means and to produce a voltage proportional to the mass of the room.   Apparatus according to claim 20, characterized   characterized in that it further comprises surface optical detection means (54) for determining the surface of the workpiece after it comes into contact with the piezoelectric means, and microprocessor means (20) connected to the power supply means. integration and the surface optical detection means, in order to compare the output signals of the integration means and the surface detection means with predetermined values of   mass of the workpiece and surface of the workpiece to determine undermine if said piece is valid.   22. Apparatus according to claim 21, characterized   in that the means for translating   take a handle (98), a box-like member (102) for receiving the workpiece of said workpiece receiving means, and a projection (100) for   connect the handle to the box-like element.   23.Apparatus according to claim 22, characterized   in that the coin receiving means comprise   a front face (80) having said coin receiving slot and further having a slot (106) for receiving said projection between the handle and the box-like member forming part of the coin translation means; apparatus further comprising a base (114) substantially perpendicular to the end face of the workpiece receiving means such that movement of the handle causes said box-like member to translate said workpiece from the slot area to the workpiece drop zone of the room   which is located at the edge of the base.   24. Apparatus according to claim 23, characterized   characterized in that the base of the coin receiving means has apertures (112) similar to a   grate to allow the passage of moisture.   25. Apparatus according to claim 24, characterized   characterized in that the parts translation means further comprises a flange (109) connected to the handle to normally close said slot under the effect a spring (99).   Apparatus according to claim 25, characterized   characterized in that it further comprises a switch (44) which is connected thereto, the translation of the handle to bring the piece down along the chute causing the contacting of the box-like element with the switch and the actuation of the latter   then produces a wake-up signal for the micro-means processor.   27. Apparatus according to claim 26, characterized   in that the coin receiving means comprise   In addition, a cap (108) is attached to said face   front of the means for receiving parts to protect   the coin slot of precipitation and ries.