GB2187319A

GB2187319A - Coin operated device

Info

Publication number: GB2187319A
Application number: GB08701655A
Authority: GB
Inventors: Peter Geoffrey Williams; Thomas Charles Smith
Original assignee: ELECTRONIC RENTALS GROUP PLC
Current assignee: ELECTRONIC RENTALS GROUP PLC
Priority date: 1986-01-27
Filing date: 1987-01-26
Publication date: 1987-09-03
Also published as: GB8601911D0; GB8701655D0

Abstract

A coin operated device for controlling the time for which an electrical current is supplied to an electrical load (14) such as a television receiver comprises a coin detector (22, 24), a load current detector (18, 42, 44,46), and a load switching relay (16). Coupled to the coin detector, load current detector and relay is a control circuit which is largely embodied on a LSI chip (28). The control circuit includes an allowed time store (40) which stores a credit time according to the number of coins inserted from time to time in the device, the allowed time being incremented by a preset amount with each coin inserted and decremented during the time that current above a certain value is drawn by the load (14), as detected by the load current detector (18, 42, 44, 46). The device has a display (54) for indicating either the remaining credit time as stored in the allowed time store (40) or the time of day. Provision is made for electronically reading the total number of coins inserted via a coin total serialising circuit (62) and a set of terminal (64) to enable detection of collector fraud. <IMAGE>

Description

SPECIFICATION Coin operated device This invention relates to a coin operated device, more particularly, a device for controlling and charging for the time that an electric current is supplied to a load.

Such devices are required for, for example, controlling the lights on public squash courts or billiard tables, and the use of rented television sets. Especially when intended for use in association with rented television sets in the home, the customer finds conventional coin operated devices unacceptable insofar that their purpose is obvious for all to see.

Another problem is security. A dishonest customer or employee of the rental company who can gain access to conventional devices may be able to indicate a lower total than was actually collected.

One object of the invention, at least in preferred embodiments thereof, is to avoid or mitigate the disadvantages associated with conventional coin collection devices.

According to this invention, a coin operated device for controlling the time for which an electrical current is passed through a load comprises a coin detector, a load current detector, a load switching device, and control means compled to the coin detector, the load current detector and the switching device, the control means including an allowed time store and being arranged to increment a allowed time stored in the store in response to a detected coin insertion and to decrement the stored allowed time in response to a detected load current, the control means being further arranged to operate the switching device so as to cut off the supply of current to the load when the stored allowed time reaches zero or some other predetermined value.

In the preferred embodiment, the device includes a display on which the remaining credit time or time of day can be displayed as required.

An embodiment of the invention will now be described by way of example with reference to the accompanying drawing which is a block circuit diagram of a coin operated device intended for use in conjunction with a rented television set.

Referring to the drawing, a preferred embodiment a coin-operated device in accordance with the invention has a mains power input 10, a mains power output 12 for connection to a load 14 (in this case a television receiver), and, between the mains input and output, a relay 16 for applying or interrupting mains power to the load 14 depending on whether or not the user of the device has fed money into the device. Coupled between one terminal of the mains output 12 and the relay 16 is a resistance 18 for load current sensing as will be described hereinafter.

The device includes a coin detector 20 having an inclined metallic ramp 22 and a pair of flexible contacts 24 coupled to a coin counter 26. A coin of the required size rolling down the ramp 22 will connect each contact 24 in turn to the ramp to provide two pulses which, after passage through a contact 'debouncing' circuit (not shown separately), are used to clock the counter 26. The counter 26 is in the form of a register which stores a running total of valid coins inserted.

The counter 26 forms part of a control circuit, much of which is embodied in a large scale integrated (LSI) circuit 28. This integrated circuit is powered either from the mains input 10 via a transformer 30 and a power supply stage 32 or from a back-up battery 34 which is itself rechargeable from the power supply stage 32. In this way the integrated circuit 28, and in particular the coin counter 26 can be kept operative when the device is disconnected from the mains.

The insertion of a coin or coins into the device causes the generation of electrical signals representing an "allowed time" for use of the load, these signals determining the state of the relay 16. Every coin inserted increases the allowed time by a fixed time period which may be selected by switches 36 mounted inside the device casing. This is achieved by coupling the coin counter 26 to a serial muiti- plier circuit 38 so that each pulse received from the counter 26 is multiplied by a factor set by the switches 36 to result in a series of pulses which are fed to a time processing register 40. The allowed time is stored in the register 40 and is incremented by the fixed time period per coin inserted. This means that the user may, if desired, feed several coins into the device to build up an allowed time of several of the periods.

The register 40 has a second input for decrementing the allowed time at times when a current of greater than a predetermined value is supplied to the load 14 from the mains input 10. Coupled across the resistance it is a load current detector circuit comprising a pair of transistors 42 and 44 biased by diodes so as to conduct on alternate cycles of the alternating voltage developed across the resistance 18 by a load current in excess of a predetermined amplitude. In the present embodiment the value of the resistance 18 is 1 5 ohms which means that the transistors 42 and 44 will only conduct when the load current exceeds about 100 mA, i.e. when the television receiver is switched on as opposed to being in the "stand-by" condition.Conduction of the transistors is interrupted in the region of the zero crossing points of the load current, resulting in pulses being fed to an isolating stage 46 comprising a pair of opto-isolators connected in parallel. The filtered (d.c.) output of the isolator stage 46 is applied to the decrementing input of the register 40. Decre menting of the register 40 is locked by a timing pulse generator 48 which feeds one pulse per minute to the register, using a 100 Hz signal derived from the power supply stage 32 as a reference. Provided that the allowed time stored in the register 40 is greater than zero, the relay 16 is kept energised via output 50 of the register 40 and the relay driver stage 52. If the allowed time reaches zero, the relay is de-energised, and the current supply to the load is cut-off.

To provide the user with an indication of the credited time stored in the register 40, a digital display 54 is coupled via a display driver 56 to the register 40, the driver 56 feeding the appropriate signals to the display 54 when a push-button 'CR' on the front panel of the device is operated. At other times, the display 54 indicates the time of day, the necessary signals being generated by a 12 hour time-of-day clock circuit 58 coupled to the timing pulse generator 48. Three further push-buttons (labelled 'HR', 'MIN', and 'SET' in the drawing) allow the time-of-day display to be adjusted. The ability to display the time of day allows the device to have the appearance of a clock, which can be located in full view on, or beside, a rented television receiver without embarrasment to the user.As an alternative, the device may incorporate a radio receiver circuit to enable the device to be disguised as a radio with or without alarm facilities. In both cases, the design of the device cabinet is preferably such that the device is stable on a flat surface and requires no mechanical connection to the television set or other appliance.

The above description has been concerned with the operation of the device as a means of controlling the application of power to an electrical load in response to the insertion of coins. The preferred embodiment of the invention also incorporates features advantageous in the collection of coins from the device, and particularly in the prevention of fraud by the user and the collector.

Coins which are inserted into the device and which pass along the ramp 22 fall into a coin receptacle which is removably housed within the device. Removal of the receptacle is only possible, in normal circumstances, by operation of a simple barrel lock to which only a collector employed by, for example, the owners of the television receiver or other appliance to which the device is connected. Associated with the coin receptacle is a switch 60 operated when the receptacle is removed. By arranging for operation of the switch 60 more than twice to set a flag in a storage device forming part of the battery or mains powered integrated circuit 28, a record of any unauthorised removal of the receptacle can be kept.The storage device forms part of a coin total serialising circuit 62 which additionally serves as an electronic means of reading out the total number of coins fed into the device since the last visit by the collector. The coin total serialising circuit 62 is coupled to some of a set of terminals 64 in a socket mounted so as to be accessible from outside the device only when the coin receptacle is withdrawn. Others of the terminals 64 are coupled to an electrically erasable programmable readonly memory (EEPROM) 66 arranged to store a serial number unique to the device. When the collector comes to collect coins from the device, he removes the coin receptacle and counts the coins.The terminal is connected to the device via the socket terminals 64, and the EEPROM interrogated to read out the device serial number so that further data to be read from the device is associated with that number. Following this the total number of coins fed into the device is read in serial form from the coin counter via the coin total serialising circuit 62, this number being stored in the portable unit without being available to the collector, enabling detection of collector fraud when the unit is later coupled to a central machine at the rental company's offices, and also enabiing updating of the relevant customer's account. At the same time, any setting of the illegal receptacle opening flag is read from the coin total serialising circuit so that the collector can determine whether the receptacle was removed prior to his removing of it, indicating a possible customer fraud. Finally the coin counter contents and any illegal opening flag are reset, the portable unit is disconnected, and the coin receptacle replaced so that the device is once again ready for use.

Claims

1. A coin operated decive for controlling the time for which an electrical current is passed through an electrical load, comprising a coin detector, a load current detector, a load switching device, and control means coupled to the coin detector, the load current detector and the switching device, the control means including an allowed time store and being arranged to increment a allowed time stored in the store in response to a detected coin insertion and to decrement the stored allowed time in response to a detected load current, the control means being further arranged to operate the switching device so as to cut off the supply of current to the load when the stored allowed time reaches zero or some other predetermined value.

2. A device according to Claim 1, further comprising a display indicating the stored allowed time and the time of day.

3. A device according to Claim 1 or Claim 2, wherein the control means includes circuitry coupled to the coin detector for counting and storing the number of coins inserted into the device.

4. A device according to Claim 3, wherein the control means includes circuitry operable to multiply the said stored number by a predetermined factor for incrementing the allowed time store by a predetermined time for each coin inserted.

5. A device according to any preceding claim, wherein the load current detector is arranged to provide an output signal to the control menas for decrementing the allowed time store only when the load current exceeds a predetermined value.

6. A device according to any preceding claim, including means for coupling the control means to an external unit, and circuity for transmitting information representing the number of coins inserted into the device to the external unit.

7. A device according to claim 3, wherein the coin detector has at least two contacts arranged to cause generation of respective sequential pulses when coin insertion is detected, and wherein the detector and the circuitry for counting and storing the number of coins inserted are operable together both when the device is coupled to a mains power supply and when the device is powered from an internal battery.

8. A coin operated device constructed and arranged substantially as herein described and shown in the drawing.