GB2308831A - Remotely-controlled golf trolley - Google Patents

Abstract

Apparatus for attachment to a directly controlled powered golf trolley to convert it to a remotely (radio) controlled trolley. A receiver 14 includes motor control means TRy connectable in tandem with the final motor control stage TRx of the trolley; a transmitter 18 signals to the receiver. The transmitter produces an initial pulse for starting the trolley and thereafter automatically produces a series (of limited length) of short pulses, with the receiver stopping the trolley if it ceases to receive the series. The receiver also stops the trolley if it detects a second pulse of length greater than the length of the short pulses. The initial pulse from the transmitter is of variable length, for setting the receiver to produce a desired speed. A steering control unit can also be provided.

Description

Golf Trolleys The present invention relates to golf trolleys, and more particularly to manually controlled powered trolleys.

Playing a game of golf involves carrying a considerable number of clubs around the golf course. This can be done by a caddy. but for those who do not want to employ a caddy. golf trolleys have long been available. A golf trolley consists essentially of a wheeled frame carrying a bag containing the clubs.

This can be pulled around the course with much less effort than carrying the bag.

Powered golf trolleys have been developed for those who do not want even to pull the trolley. The simpler type of powered trolley is manually (ie directly) controlled, by a control device mounted on the trolley; the trolley is driven by the motor but is guided manually. A remotely controlled type of trolley has also been developed, in which the trolley is controlled by a radio link from a handheld control unit; the control system of this type of trolley incorporates steering control mechanism as well as drive control, so that it can be steered by remote control es well as having its starting, stopping, and speed remotely controlled.

These various types of trolley have, of course, different costs. The handpulled trolley is the cheapest; the directly controlled powered trolley is considerably more expensive; and the remotely controlled trolley is considerably more expensive again.

I have realized that a remote control function can be added to a directly controlled powered trolley relatively cheaply, giving a trolley which, while it may not have the flexibility of a standard remotely controlled trolley, is considerably cheaper than such a standard remotely controlled trolley.

According to one aspect of the invention there is provided remote control apparatus for a directly controlled powered trolley, comprising a receiver inclu- ding motor control means connectable in tandem with the final motor control stage of the trolley, and a transmitter for signalling to the receiver.

The motor control means is preferably connected in parallel with the final motor control stage of the trolley, with the trolley control device being turned off for remote control operation. However, it may not be easy to achieve access to both sides of the trolley control device for fitting the motor control means.

In this case, the motor control means may instead be connected in series with the final motor control stage of the trolley.

The transmitter is preferably arranged to produce an initial pulse for starting the trolley and thereafter to automatically produce a series (preferably of limited length) of short pulses. with the receiver stopping the trolley if it ceases to receive the series. The receiver is also preferably arranged to stop the trolley if it detects a second pulse of length greater than the length of the short pulses. With the preferred arrangement of the motor control means being in parallel with the final motor control stage of the trolley, the initial pulse from the transmitter is preferably of variable length, for setting the receiver to produce a desired speed.

The transmitter and receiver preferably include a matched coder and decoder to minimize the risk of interference.

The invention also provides a directly controlled powered trolley including the receiver of such remote control apparatus, and such a trolley together with the transmitter of such remote control apparatus.

In its preferred form, the present invention thus provides a system in which a directly controlled golf trolley can be remotely controlled, with the transmitter requiring only a single button. The button is pressed once to start the trolley and again to stop it, with the speed of the trolley being determined by how long the button is held down for on the first press. The system is also fail-safe, with the trolley stopping automatically after a predetermined time or if it gets out of range of the transmitter.

The present invention also provides a development allowing steering control.

A golf trolley with remote control apparatus embodying the invention will now be described, by way of example, with reference to the drawings, in which: Fig. 1 is a block diagram of the golf trolley; Fig. 2 is a more detailed diagram, mainly in block form, of the trans mitter of the control apparatus; Fig. 3 is a more detailed diagram, mainly in block form, of the receiver of the control apparatus; and Fig. 4 shows, in simplified top view, a steering unit.

The circuits of the control apparatus are shown in simplified form.

Referring to Fig. 1, a standard directly controlled golf trolley comprises a motor M1, a battery BATS, and a manual controller 10 connected in series. The controller consists of a transistor TRx which is controlled by a pulse width modulator PWM which is in turn controlled by a potentiometer P. The battery has two terminals, red R and black BK, which are connected via standard connections (eg screw connections, or crocodile clip type connectors for quick release) to the manual controller 10 as shown. The motor M1 has two terminals, red R and blue BL, which are also connected via spade type connectors to the manual controller as shown, with the R connection being shared with the R connection from the battery.The R terminal connector of the motor consists of a spade prong Il-R connected to the battery and a spade socket 12-R connected to the motor; the BL terminal connector is similar.

In a standard directly controlled golf trolley, the prong I l-R of the R motor connector is plugged directly into the socket 12-R, and similarly for the BL motor connector. To add the control apparatus receiver to the trolley, 3 connections (R, BL, and BK) have to made from it to the existing circuitry of the trolley. For the R connection, the R connector of the motor is opened up, and between its prong and socket a prong-and-socket element 15-R is inserted; this element 15-R includes a lead into the receiver 14. The BL connection to the receiver is made similarly. The BK lead of the receiver 14 consists of a lead 16 terminating in a washer. To connect this BK lead, the existing connection from the existing controller 10 to the BK terminal of the battery BAT1 is released, the washer on the lead 16 placed over the battery terminal, and the connection from the controller 10 replaced.

As shown in Fig. I, the receiver 14 includes a transistor TRy which is connected between the BL and BK terminals, in parallel with the existing transistor TRx, when the receiver is added to the trolley. For remote control, the controller 10 is turned off (ie set to leave the motor M1 de-energized). The motor can then be controlled by the receiver 14, with the transistor TRy being controlled by logic circuitry 17 which is in turn controlled by a transmitter 18.

The receiver 14 is permanently powered by the battery voltage applied between its R and BK leads.

Fig. 2 is a diagram of the transmitter 18, which is divided broadly into a control section 20 and a transmission section 21. The control section is permanently powered from an internal battery BAT2; to minimize power drain on the battery, the transmission section is only powered when signals are to be transmitted.

The control section includes a control switch SI. Closing this switch applies a positive voltage to the gate of a FET transistor TR1, turning this transistor on. This turns on a second FET transistor TR2, which powers the transmission section 21 of the transmitter. Switch S1 is coupled to transistor TR1 via an RC circuit C4-R5, which ensures that TR1 is held on for at least a minimum time of approximately 250 ms; if switch S1 is held down, TR1 will of course remain on for as long as switch S1 is held closed (plus the 250 ms).

The control section 20 also includes a counter CTRI, which has coupled to it suitable RC circuitry (not shown) forming an oscillator to drive the counter.

This counter is normally at a maximum count which produces a high signal at its top stage output MAX, which is fed back to a disable input DIS; this high signal therefore holds the counter at the high count. An intermediate stage INT is coupled via an RC circuit R3-C2 to the gate of TR2. The switch S1 is coupled to the reset input RST of this counter.

When S1 is pressed the counter is reset and starts to count. Its intermediate stage INT changes state approximately every 3 s, and its output is shaped by the RC circuit R3-C2 to a short pulse which turns TR2 on briefly (for approximately 100 ms). The counter continues to count for approximately 150 9, when it reaches its maximum count; it is then held in that state until the switch S1 is pressed again. Thus the counter generates a series of short (100 ms) pulses (keep-alive pulses) at 3 s intervals for 150 s.

When transistor TR2 is turned on, the transmission section 21 is energized.

This turns on a codec (coder-decoder) circuit CODEC1, which is connected to a set of links which are broken in a selected pattern. An RF transmission circuit RFI is also energized via TR2, transmitting at typically 418 MHz. The codec circuit passes the link pattern repeatedly to the RF transmission circuit, modula ting the transmitted signal with the link pattern. The link pattern is therefore repeatedly transmitted each time transistor TR2 is turned on. To prevent interference between different control apparatuses (and trolleys), each control apparatus is given a different pattern or code. A light emitting diode LED1 is also turned on when TR2 is turned on, providing a visual indication of when the transmitter is actually transmitting.

Fig. 3 is a diagram of the receiver 14. As noted above, the receiver is permanently powered by the battery voltage from the trolley. Voltage dropping and regulation circuitry (not shown) is preferably provided for the appropriate parts of the receiver. (If desired, the receiver could be connected to the trolley circuit by a 2-wire connection to the BL and BK terminals, omitting the R connection. If that is done, it will have to include power storage means such as a small rechargeable battery for storing power while the transistor TRy is off, so that the receiver remains energized when transistor TRy is turned on and t h e voltage across it falls to zero.) An RF receiver circuit RF2 receives signals from the transmitter (Fig. 2), and demodulates them and feeds them to a codec CODEC2.This is connected to a set of links which are broken in the same pattern as the codec in the transmitter, and produces an output signal if the demodulated signal has thbt pattern.

The output of the codec CODEC2 is fed to a flip-flop FF1, which operates in "toggle" mode, ie each input signal changes its state. Thus when the switch on the transmitter is first pressed, the flip-flop will be set to the ON state, in which the transistor means TRy (Fig. 1 ) are turned on, so driving the trolley.

When the switch on the transmitter is pressed again, the flip-flop will change state to the OFF state, turning off the transistor means TRy and so stopping the trolley. An RC circuit Rl-C4 is connected to a reset input RST1 of this flipflop to force it to the OFF state when the receiver is first powered; this ensures that the trolley does not start up when the receiver is first powered.

Codec CODEC2 is coupled to the flip-flop FF1 through an RC circuit R8-C3, which has a time constant of approximately 300 ms. A signal must therefore last for at least this time before flip-flop FF1 will respond. This provides good protection against interference from stray signals, because although a stray signal may accidentally match the link pattern of the codecs for a short period, it is unlikely to do so for 300 ms or more. This also prevents the flip-flop from being changed by the keep-alive pulses from the transmitter.

When flip-flop FFI is in the ON state, it drives a pulse width modulator circuit PWM2, which in turn drives a transistor T8 which is connected between the BL and BK terminals; this transistor is the transistor TRy of Fig. I. The duty ratio of the modulator starts at a low value corresponding to the initial low speed of the trolley. The modulator is also fed from a digital-to-analog converter D/A (which may consist of a set of 4 resistors) which is driven by a counter CTR2. The output from the codec CODEC2 is fed to the counter CRT2 via an RC circuit R6-C10 and a transistor T5.

The RC circuit has a time constant of approximately 3 s, so the counter starts to count if the signal from the codec lasts for more than that time. As the counter counts up, so the duty ratio of the modulator PWM2 increases, so increasing the speed of the trolley. Thus when the switch on the transmitter is pressed, the trolley immediately starts to move, at its minimum speed; if the switch is held down for more than 3 s, its speed starts to increase, and rises until the switch is released or it reaches its maximum speed.

The flip-flop FF1 feeds the reset input RST of the counter CTR2, so that when the flip-flop changes state and the trolley stops, the counter is reset.

This means that the trolley will always start from the minimum speed.

The output of the codec is also fed to a transistor T2 which is connected across a capacitor C1 forming part of a RC circuit C1-R4 with a time constant of approximately 10 s. This RC circuit feeds a reset input RST2 of the flip-flip FF1. The initial signal from the codec, which turns flip-flop FF1 on, also turns transistor T2 on and discharges C1, and the subsequent 100 ms keep-alive signals at approximately 3 s intervals (approximately 0.3 Hz) keep C1 effectively discharged. However, when the keep-alive pulse sequence ends or is interrupted (eg by interference, the trolley going out of range of the transmitter, or blocking of the signal path), Cl charges and energizes the RST2 input of FF1. FF1 is then turned off, stopping the trolley.

The signal from the codec is also fed to a light emitting diode LED2 via a driver circuit DR. The LED indicates when signals from the transmitter are actually being received by the receiver.

To protect the transistor T8 from the back emf of the motor M1 (Fig. 1) and accidental reversal of the connections, a thyristor T10 is connected between the R and BL connections. A transistor T7, controlled by a zener diode Z2 and a resistor R6, ensure that T10 cannot conduct under these circumstances. A zener diode Z1 and a diode D8 are connected across T8 to prevent high voltage damage during the few microseconds which T10 takes to turn on. (The existing manual controller 10 may contain similar circuitry to protect the transistor TRx.) Positive temperature coefficients result in the conduction voltage of transistor T8 rising as this transistor becomes hot.A series circuit or resistors R10 and R20 and a transistor T6 forms a current limit circuit, by monitoring this conduction voltage of T8, reducing the current limit and also preventing the motor from overheating.

As noted above, an alternative arrangement is possible, in which the receiver is connected in series with the manual controller 10. There ere 2 main modes in which this alternative arrangement can be operated. In one mode, the existing manual trolley control device is set to full on, ie maximum speed, and the remote control acts (as above) as a proportional speed control device. In the other mode, the existing manual trolley control device is set to the desired speed, with the remote control acting as a simple onXoff control.

In this alternative arrangement, the receiver will normally be connected between the manual controller and the motor, although connection between the manual controller and the battery is possible. The receiver again preferably has 3 connections, the third connection being made to the R side of the motor M1, to improve the power supply to the receiver. Since the two controllers together will normally be set to give a speed somewhat below maximum, the voltage to the receiver will not be steady, so the receiver will usually have to include a rechargeable battery or similar power storage device.

As so far described, the apparatus is an attachment for a golf trolley which allows the trolley to have its speed remotely controlled. Such a trolley will only travel in a straight line, so any change of course requires the trolley to be manually turned to point in the desired direction.

Fig. 4 shows a further attachment 30 which allows the trolley to be steered remotely as well as having its speed remotely controlled. A powered trolley will normally have a pair of driving wheels and further free wheel (or pair of wheels) set in front of or behind the driving wheels. To use the attachment 30, the further wheel or wheels are removed and replaced by the attachment, which is attached to the trolley at its rear 31. The attachment includes a pair of steering wheels 32.These steering wheels must be sufficiently far forward of the main driving wheels of the trolley for the trolley to be steered by adjustment of the direction of these wheels; if appropriate, the attachment may be attached via a rod (not shown) to increase the distance between the steering wheels and the main driving wheels of the trolley. (This will also increase the stability of the trolley.) The steering wheels 32 are mounted on a shaft 33 which is mounted for free rotation in a bearing 34 which can be turned about e vertical axis by means of an arm 35. The other end of arm 35 is attached to e nut 36 mounted on a threaded shaft 38, so that rotation of the shaft 38 turns the shaft 33 and hence the wheels 32.The distance between the bearing 34 and the nut 36 will vary as the nut moves along the shaft 38, and the arm 35 is formed in two parts coupled together by a sliding sleeve 37 to allow for this. The shaft 38 is mounted in a pair of bearings 39, and has attached to it a gear 40 which engages with 8 further gear 41 on the shaft 42 of a motor M2. This motor is driven in one or other direction to turn the steering wheels in the one or other direction.

The coupling of the motor to the steering wheels via the gearing 40-41 and the shaft 38 means that any shocks which are applied to the steering wheels (eg as a result of travel over rough ground) are largely buffered by the screw threaded shaft 38, which can absorb considerable shock.

The motor M2 is powered from the battery BAT1 (Fig. 1) and controlled by the receiver circuitry (Fig. 3), which is in turn controlled by the transmitter circuitry (Fig. 2). For this, the transmitter and receiver must be suitably modified. Essentially, they must provide 3 signals: the drive motor Ml control signal (as already described) and the steering motor M2 left and right signals.

This may be done by suitably adapting the codecs. Certain codecs are available in which the last 2 bits are controllable for codingXtransmission and are decodable to provide 4 distinct outputs for decoding/reception. By using this technique, the 3 different signals required can be transmitted. The 4th bit pair combination can simply not be used, or 2 bit combinations can be combined for eg the main drive signal, to increase reliability in the presence of interference.

Alternatively, simple tone signalling can be used instead of the coding described above, using 3 distinct tones for the 3 signals. This renders the system more liable to interference, but I have found that it increases the effective range of the system.

A potentiometer 43 is coupled to the nut 36 to act as a position sensor.

This potentiometer is coupled to a circuit (not shown) which performs 3 functions. First, the circuit senses the position (ie direction) of the steering wheels and controls the motor M2 to return them to the straight-ahead position in the absence of a steering control signal from the transmitter. This means that the trolley will travel in a straight line once its direction has been adjusted by the user, rather than travelling in a circle. Second, the circuit detects when the nut 36 reaches either of a pair of predetermined positions and turns off any steering signal when either of these positions (limit or extreme positions) has been reached. This prevents over-travel of the nut 36 and possible jamming against the bearings 39. Third, it detects when the nut 36 fails to move in response to a steering signal and turns off any steering signal if this happens.

This prevents stalling and overheating of the motor M2.

Obviously the details of this steering attachment unit can be varied, eg by coupling the steering shaft bearing 34 to the motor M2 directly through stepdown gearing, or through a belt or chain and pulley coupling.

Claims (16)

Claims

1 Remote control apparatus for a directly controlled powered trolley, comprising a receiver including motor control means connectable in tandem with the final motor control stage of the trolley, and e transmitter for signalling to the receiver.

2 Apparatus according to claim I wherein the motor control means is connectable in parallel with the final motor control stage of the trolley, with the trolley control device being turned off for remote control operation.

3 Apparatus according to claim 1 wherein the motor control means is connectable in series with the final motor control stage of the trolley.

4 Apparatus according to claim 2 wherein the transmitter is arranged to produce an initial pulse for starting the trolley and thereafter to automatically produce a series (preferably of limited length) of short pulses, with the receiver stopping the trolley if it ceases to receive the series.

5 Apparatus according to claim 4 wherein the receiver is also arranged to stop the trolley if it detects a second pulse of length greater than the length of the short pulses.

6 Apparatus according to any of cleims 2, 4, and 5, wherein the initial pulse from the transmitter is preferably of variable length, for setting the receiver to produce 8 desired speed.

7 Apparatus according to any previous claim wherein the transmitter and receiver include a matched coder and decoder.

8 A directly controlled powered trolley including the receiver as defined by any previous claim.

9 The trolley of claim 8 together with the transmitter of any previous claim.

10 A trolley according to either cof claims 8 and 9 including a steering attachment having steering wheels whose position is controllable by the transmitter.

11 A trolley according to claim 10 wherein the steering attachment comprises a pair of steering wheels mounted on a shaft carried in a movable bearing controlled by a steering motor which is controlled by the transmitter.

12 A trolley according to claim 11 wherein the steering motor is coupled to the bearing by means of a threaded shaft carrying a nut coupled by an arm to the bearing.

13 A trolley according to either of claims 11 and 12 including a position sensor for sensing the position of the steering wheels and a circuit responsive thereto to control the steering motor.

14 Remote control apparatus for a trolley substantially as herein described and illustrated.

15 A golf trolley substantially as herein described and illustrated.

16 Any novel and inventive feature or combination of features specifically disclosed herein within the meaning of Article 4H of the International Convention (Paris Convention).