GB2095565A

GB2095565A - Ball ejection machine

Info

Publication number: GB2095565A
Application number: GB8209306A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1981-04-01
Filing date: 1982-03-30
Publication date: 1982-10-06
Also published as: AU8139682A

Abstract

A ball ejection machine, especially suitable for ejecting squash balls, at a speed appropriate to the game of squash, is able to reproducibly serve a ball in exactly the same direction a number of times, and comprises an injection means comprising a pair of counter-rotatable rollers (2,3), a feed unit (4) for feeding balls one at a time to the ejection means, and a ball storage unit (5) for storing a supply of balls for feeding to the feed unit (4). <IMAGE>

Description

SPECIFICATION Ball ejection machine The present invention relates to a ball ejection machine, particularly for squash balls.

When coaching a pupil in the game of squash, it would be advantageous to be able to reproducably serve a ball in exactly the same direction a number of times. This would allow the pupils to perfect a particular shot. In squash, it may be necessary to deal with a ball rebounding off 1, 2, or 3 walls, before being hit by the player. Moreover, the ball must be served at a speed appropriate to the game of squash.

The present invention provides a ball ejection machine which comprises -an ejector comprising a pair of counterrotatable rollers, drive means connected for rotating the rollers, -a feed unit for feeding balls one at a time to the ejector, and -a ball storage unit for storing a supply of balls for feeding to the feed unit.

In general, balls are fed by gravity from the ball storage unit along a duct to the feed unit which allows them to roll one at a time to the ejector. In the ejector, a ball is squeezed and gripped between the rotating rollers before being ejected at an appropriate speed.

When the machine is to be used to eject squash balls, the rollers are preferably spaced apart a distance less than a squash ball diameter so as the compress the ball prior to ejection.

It is well known that squash balls need to be "played" up to the correct temperature before a game is commenced. Thus, in a preferred embodiment, the machine comprises a hot air blower for heating the balls prior to ejection. Usually, the blower will eject hot air into the duct upstream of the feed unit. Other heating means may be used as appropriate, for example a radiant heater.

It is often advantageous for each roller to have a rubber outer curved surface for gripping the ball more effectively. Preferably, the rubber outer surface is ribbed. Usually, the ribs will extend axially of the roller.

The drive means will generally comprise at least one motor, for example an electric motor. Usually, a pulley belt connects the rollers to the motor. In a preferred embodiment, there is a separate motor connected to each roller.

In order to more accurately direct the balls, the machine preferable further comprises a cylindrical outlet nozzle through which the ball passes after being accelerated by the rollers.

Generally, the machine will be mounted on a trolley which may be swivelled in all directions so as to vary the line and elevation of the machine so that balls may be directed in any chosen direction.

The feed unit is designed to feed balls one at a time to the ejector. A variety of constructions are possible. In one embodiment, the feed unit comprises a rotatable drum having therein a cavity for accepting a single ball, rotation of the drum delivering the ball towards the ejector, and rotation means for rotating the drum.

In another embodiment, the feed unit comprises a pair of plungers disposed in the duct leading to the ejector, the plungers being spaced along the duct so as to define therebetween a space for receiving a single ball, outside the ducts the plungers being connected to either side of a rocker such that as one plunger is raised to release the ball, the other plunger is lowered behind the ball to prevent release of further balls, and means for rocking the rocker.

Generally, the machine will also comprise control means to control the rate at which balls are ejected. The control means may be manually or automatically operated. In manual operation, a ball is ejected as desired in response to a control signal. In automatic operation, balls are ejected at predetermined time intervals one after the other.

The control means may be operated using a remote controller either at the end of a long lead or using a ultrasonic transmitter carried by the coach or player, which activates a receiver controlling the feed unit.

Preferably, the roller drive means runs continuously when activated by a main control switch. Preferably, the feed unit is operated by an electric motor driven gearbox having a crankdisc cam, which is connected by a linkage to the feed unit, e.g. the rocker mentioned above. A microswitch is activated by the crankcase cam and is arranged to switch off the feed unit after one revolution of the cam. In automatic operation, the microswitch is bypassed.

Generally, the ball storage unit will comprise one or more cylindrical tubes disposed in a generally upstanding manner so as to feed the balls by gravity. Advantageously, there are at least two tubes arranged to be rotatable about an upstanding axis so as to bring the next tube full of balls into line above the duct leading into the feed unit, when the first tube becomes empty. Usually, there are 4 tubes and 1 2 balls in each tube.

An embodiment of the present invention will now be described by way of example only with reference to the accompanying drawing which shows a part cross-sectional view of an embodiment of the invention.

The drawing shows a squash ball ejection machine which comprises an outer casing 1 shown in chain-dotted lines, a pair of counter rotating rollers 2 and 3, a feed unit 4 and a ball storage unit 5.

Each roller is driven by a respective electric motor disposed in the casing but not shown in the drawing. Each roller is connected by means of a pulley belt 6 (only one shown) to the respective electric motor. The outer cylindrical surface of each roller is provided with a ribbed rubber coating 7 for gripping the squash ball. The spacing between the rollers is slightly less than the normal diameter of a squash ball so as to compress the ball prior to ejection.

A nozzle 8 is disposed downstream of the rollers for directing the ball, which is ejected in the direction of the arrow.

A curved duct 9 connects the ball storage unit with the ejector rollers. The feed unit 4 controls the feeding of the balls by gravity to the ejector rollers. The feed unit comprises a pair of plungers 10 and 11 connected to either end of a rocker 1 2. The rocker is pivotally mounted at 1 3 and arm 14 is rigidly attached to the rocker, and a rod 1 5 is pivotally mounted to the free end of the arm.

The rod is eccentrically mounted at its other end on a cam 1 6 rotatable by means of an electric feed motor (not shown), Rotation of the cam causes operation of microwash 1 7 which controls the feed motor via a control unit (not shown).

Hot air for preheating the squash ball is blown through pipe 18 from a fan and heater (not shown) into the duct 9 so as the preheat the waiting balls.

The ball storage unit 5 comprises four cylindrical tubes 19, each tube being capable of holding 1 2 balls. Thus, the total capacity of the ball storage unit is 48. Also, 4 balls may be accomodated in the upper portion of the duct 9. Thus, the total capacity of the machine is 52 balls.

The four tubes 1 9 are mounted to a central shaft 20 which is rotatable in a bush 21. Stop means are provided as appropriate for aligning the appropriate tube with the upper inlet to the duct 9.

The machine may be operated as follows.

The four ball tubes 1 9 and the upper part of duct 9 are filled with squash balls. The machine is set to either manual or automatic.

The machine is turned on, causing the rollers 2 and 3 to rotate. In response to a start signal cam 1 6 is rotated by the feed motor to operate the feed unit 4. Rotation of the cam 1 6 causes sideways movement of the rod 1 5 and pivoting of the arm 14. The arm 14 causes rocker 1 2 to rock in an anticlockwise direction, thereby raising plunger 11 and lowering plunger 10. A ball is thereby allowed to pass into the space between the two plungers 10 and 11. Further rocking of the rocker 1 2 causes plunger 10 to be raised again thereby allowing the ball to roll down duct 9 towards the rotating rollers 2 and 3. The plunger 11 is lowered behind the ball, thereby preventing release of further balls stored in the upper part of the duct 9.

The released ball passes between the rollers 2 and 3 and is gripped and compressed by the ribbed rubber coating 7 before being ejected at high speed through the nozzle 8.

When the machine is set to manual operation, the feed motor stops after each revolution of the cam 16. The start signal which starts the feed motor bypasses microswitch 16. At the end of one revolution the microswitch turns off the feed motor.

In the automatic operation, the microswitch is bypassed and the feed motor and cam rotate continuously at the rate of one revolution every 4 seconds.

In order to change the direction of ejection of the ball, the entire machine is swivelled on its stand.

Claims

1. A ball ejection machine which comprises an ejector comprising a pair of counterrotatable rollers, drive means connected for rotating the rollers, a feed unit for feeding balls one at a time to the ejection means, and a ball storage unit for storing a supply of balls for feeding to the feed unit.

2. A machine according to claim 1 adapted to eject squash balls wherein the rollers are spaced apart a distance less than a squash ball diameter so as to compress the ball prior to ejection.

3. A nachine according to claim 2, which further comprises a hot air blower for heating the balls prior to ejection.

4. A machine according to any preceding claim, wherein each roller has a ribbed rubber outer curved surface.

5. A machine according to any preceding claim wherein the drive means comprises a separate motor for driving each roller.

6. A machine according to any preceding claim which further comprises a cylindrical outlet nozzle through which the ball passes after being accelerated by the rollers.

7. A machine according to any preceding claim wherein the feed unit comprises a rotatable drum having therein a cavity for accepting a single ball, rotation of the drum delivering the ball toward the ejector, and rotatable means for rotating the drum.

8. A machine according to any one of claims 1 to 6 wherein the feed unit comprises a pair of plungers disposed in a duct leading to the ejector, the plungers being spaced along the duct so as the define a space for receiving a single ball, outside the duct the plungers being connected to either side of a rocker such that as one plunger is raised to release the ball, the other plunger is lowered behind the ball to prevent release of further balls, and means for rocking the rocker.

9. A machine according to any preceding claim which further comprises a remote controller for controlling the ejection of the balls, the remote controller comprising an ultrasonic portable transmitter and a receiver controlling the feed unit.

1 0. A ball ejection machine substantially as described in conjunction with the drawings.

11. Any novel feature or combination of features disclosed herein.