WO2014174341A1

WO2014174341A1 - Ball collecting device

Info

Publication number: WO2014174341A1
Application number: PCT/IB2013/053245
Authority: WO
Inventors: Adriano LELLI
Original assignee: Lelli Adriano
Priority date: 2013-04-24
Filing date: 2013-04-24
Publication date: 2014-10-30

Abstract

A ball collecting device comprises a frame (2), moving means (4) associated with the frame (2) for moving it along a supporting surface (A) for it, collecting means (7) connected to the frame (2) and configured to collect at least one ball (100) located on the supporting surface (A), a lifting member (8) associated with the collecting means (7) for receiving the ball (100) and lifting the height of it from a lower height (Q1) to an upper height (Q2) and a container (9) connected to the frame (2) and interposed between the lower height (Q1) and the upper height (Q2) so as to receive the ball (100) from the lifting member (8) by gravity. The collecting means (7) comprise an inlet conduit (10) with an access mouth (10a) shaped to receive the ball (100) and an end portion (10b) leading to the lifting member (8) and restraint means (12) configured to at least partially occlude the access mouth (10a) and activatable when the ball (100) is inside the conduit (10) so as to prevent it from escaping.

Description

DESCRIPTION

BALL COLLECTING DEVICE

Technical field

This invention relates to a device for collecting balls, in particular tennis balls.

This invention is applied in particular to the sports sector, and in particular to tennis clubs.

One of the greatest problems in the practice of tennis has always been relative to collecting the balls scattered all over the court during the game. In effect, this often involves wasted time and energy for the players, who in most cases only have a limited amount of time to complete a match or a lesson.

Even on a competitive level, the lack of ballboys, who are present almost only among the professionals, involves significant expenditure of energy for the athlete who contrarily should rest both mentally and physically between one point and the next (or when changing sides).

Background art

Several automated devices, or robots, have been designed in the past to resolve this problem, which are capable of moving around the court to capture the balls and store them in a specific container or basket.

A first known solution consists of an automated collecting device (or robot) comprising a frame equipped with wheels and equipped with an anthropomorphic arm projecting forwards.

The arm is equipped, at a free end of it, with one or more movable opening/closing grippers for grasping/releasing the ball. The arm is hinged, at the other end, to the frame in such a way that it can tilt back to release the ball into a basket anchored at the back of the frame. Disadvantageously, this solution is rather slow because the movement of grasping, tilting backwards, releasing, tilting forwards is to be completed for each ball.

Furthermore, considering the high mobility of the balls (by rolling) on the tennis court surface, often the grippers aren't able to grasp them precisely, thus letting them escape.

Another known solution entails the presence, in replacement of the anthropomorphic arm, of a front roller which is rotatable about a horizontal axis of rotation and is equipped with three blades which are equally angularly spaced from each other (that is offset by about 120°).

The roller is programmed to rotate in the same direction as the advancing direction of the frame, so that the blade, once in contact with the ball, pushes it towards the inside of the frame.

Disadvantageously, this solution is rather imprecise because if the ball is close to the free end of the blade, the latter does not have sufficient angle of action to drag the ball inside the container (that is backwards), thus being limited to crushing it and then releasing it.

Aim of the invention

The aim of this invention is to provide ball collecting device (or robot) which overcomes the above mentioned drawbacks of the prior art.

More specifically, the aim of this invention is to provide a particularly fast and precise ball collecting device.

Furthermore, the aim of this invention is to provide a self-propelled ball collecting device capable of autonomously operating on the court.

These aims are fully achieved by the ball collecting device according to this invention, comprising a frame, moving means associated with the frame for moving it along its supporting surface, collecting means connected to the frame and configured to collect at least one ball arranged on the supporting surface, a lifting member associated with the collecting means for receiving the ball and lifting the height of it from a lower height to an upper height and a container connected to the frame and interposed between the lower height and the upper height so as to receive said ball from the lifting member by gravity.

According to the invention, the collecting means comprise an inlet conduit with an access mouth shaped to receive said ball and an end portion leading to the lifting member and restraint means configured to at least partially occlude said access mouth and activatable when said ball is inside said conduit so as to prevent it from escaping.

Preferably, the collecting means comprise at least one pushing member which is operatively active inside said conduit between the access mouth and the end portion thereof to guide the ball towards the lifting member. It should be noted that the pushing member preferably at least partially defines the restraint means, thus preventing the ball from escaping and at the same time pushing it towards the lifting member.

Brief description of the drawings

The above-mentioned and other features of the invention will become more apparent from the following detailed description of a preferred, non- limiting embodiment of it, with reference to the accompanying drawings, in which:

- figure 1 shows the ball collecting device according to this invention, during use;

- figure 2 is a perspective view of the device from figure 1 with some parts transparent;

- figure 3 is a side view of the device of figure 1 with some parts transparent;

- figure 4 is a perspective view of the device in use. Detailed description of preferred embodiments of the invention

With reference to the accompanying drawings, the numeral 1 denotes a ball collecting device, preferably for tennis balls, according to this invention.

In particular, the device 1 is usable on tennis courts as an "automated ballboy" which is activatable at least during the time intervals between one point and the next or between one game and the next.

The device 1 comprises a supporting frame 2 which extends between a front portion 2a and a back portion 2b.

The frame 2 may be unibody or tubular/reticulated.

The device 1 comprises a shell 3 (or casing), which is connected to the frame 2 and defines an inner containment compartment 3a that houses the functional components (described below) of the device 1.

This shell 3 is made of metal or of plastic material to give it increased resistance capable of enduring any knocks (by the tennis balls), which are particularly frequent when the device is used.

Preferably, the shape of the shell 3 is rounded, without any sharp edges, which increases the safety of the device 1 in the game area.

The device 1 also comprises moving means 4 associated with the frame 2 for moving it along a supporting surface A for the frame 2.

The supporting surface A for the frame 2 (in use) is nothing more than the surface of the tennis court 200.

Whatever the case, the expression supporting surface A is intended as any surface on which the device can rest with the possibility of movement. The moving means 4 may be defined by wheels 4a, 4b, tracks or rollers. Preferably, the moving means 4 comprise a plurality of wheels 4a, 4b which are partially positioned at the front portion 2a of the frame 2 and partially at the back portion 2b.

In the embodiment illustrated, the moving means 4 comprise a pair of front wheels 4a hinged on opposite sides of the front portion 2a of the frame 2 and rotatable about an axis of rotation which is substantially parallel to the supporting surface A (thus horizontal).

Furthermore, the moving means 4 comprise at least one rear wheel 4b, connected to the frame 2 at the back portion 2b of it.

In the embodiment illustrated, the two front wheels 4a have independent drive units 5.

Furthermore, in this embodiment, in addition to being rotatable about a horizontal axis of rotation (that is parallel to the supporting surface A), the rear wheel 4b is also rotatable about an axis of rotation (preferably orthogonal) that is transversal to the supporting surface A of the frame 2. Advantageously, in this way a differentiated action of the two drive units 5 between one front wheel and the other allows the rotation of the frame 2 (that is of the device 1 ).

Alternatively, steering (not illustrated) can be used, which is connected to both front wheels in such a way as to allow them to rotate on the supporting surface A (that is about an axis transversal to the surface). In an alternative embodiment, the moving means 4 comprise a pair of tracks (not illustrated) arranged on opposite sides of the frame 2 and independently movable from each other to impart rotation to the device 1. In the embodiment illustrated, the width of the frame is between 200 mm and 500 mm, preferably approximately 300 mm, and its length is between 300 mm and 600 mm, preferably approximately 400 mm.

According to the invention, the device 1 comprises a unit 6 for collecting and storing a plurality of balls 100 (preferably tennis balls) connected to the frame 2 of the device .

This unit 6 comprises means 7 for collecting one or more balls 100 and is mounted at the front of the frame 2, a member 8 for lifting the balls 100 and a container 9 connected at the back of the frame 2 so as to receive the balls 100 from the lifting member 8 by gravity.

As indicated, the collecting means 7 are connected to the frame 2 and configured to collect a succession of balls 100 located on the supporting surface A.

In particular, the collecting means 7 are positioned at the front portion 2a of the frame 2 so as to encounter the balls 100 during the advancement of the device 1 along the supporting surface A.

Preferably, the collecting means 7 comprise an inlet conduit 10 with an access mouth 10a shaped to receive at least one ball 100 and an end portion 10b leading to the lifting member 8.

In other words, the inlet conduit 10 extends (at least partially) at a height substantially equal to the supporting surface A so as to allow the introduction of the balls 100 resting on it.

Consequently, the conduit is delimited at the bottom of it, at least at the access mouth 10a, by the supporting surface A for the frame 2.

Therefore, the inlet conduit 10 extends from the access mouth 10a substantially parallel to the supporting surface A towards the back portion 2b of the frame 2.

Preferably, the access mouth 10a is dimensioned to substantially receive one single tennis ball 100 in it at a time.

Therefore, the cross section of the access mouth 10a is at least 6 cm, but less than 130 cm, wide.

Consequently, the collecting means 7 are configured to receive a plurality of balls 10 in succession, that is one at a time.

Preferably, in resting conditions, the collecting means 7 comprise a hopper portion 11 extending between a larger portion, which is distal from the lifting member 8, and a smaller portion, which is proximal to the lifting member 8, so as to guide each ball 100 at least into an initial portion of the conduit 10.

According to the invention, the collecting means 7 comprise restraint means 12 configured to at least partially occlude the access mouth 10a and activatable when the ball 100 is located inside said conduit 10 in order to prevent the escaping thereof. Consequently, the restraint means 12 are configured to be activated when the ball crosses the inlet mouth 10a of the conduit 10 to prevent the ball 100 from "escaping" once it is inside the conduit 10.

In this regard, the collecting means 7 comprise a sensitive member 27 (for example a photocell, or contact sensor) configured to detect the presence of the ball close to the access mouth 10, and preferably the crossing of it by the ball 100.

Furthermore, the device 1 comprises a control unit 13 designed to receive a signal representing the crossing of the sensitive member 27 and programmed to control the activation of the restraint means 12 as a function of this signal.

Advantageously, this ensures grasping of the ball 100, which is restrained inside the conduit and therefore has no chance of avoiding being grasped by the lifting member 8.

In this regard, the collecting means also preferably comprise at least one pushing member 14 which is operatively active inside the conduit 10 between the access mouth 10a and the end portion 10b thereof to guide the ball 100 towards the lifting member 8.

In other words, the pushing member 14 is movable inside the conduit 10 to press on the ball 100 and push it to a recovery position (located at the end portion 10b of the conduit 10) where it can be engaged by the lifting member 8.

Preferably, the pushing member 14 at least partially defines the restraint means 12.

Thus, the pushing member 14 comprises at least one stop wall 14a which is movable along the conduit 10 both to prevent the ball 100 from escaping and to push on it to guide it from the access mouth 10a to the end portion 10b, and in particular into the recovery position.

Preferably, the sensitive member 27 described above is defined by a contact and/or pressure sensor located at the stop wall.

In this regard, it should be noted that the conduit 10 is equipped, inside of it, with a ramp 15 which inclined to the supporting surface A to bring the ball 100 from a first height to a second height.

More precisely, the first height corresponds substantially to the level of the supporting surface A, while the second height is at a higher level, corresponding to a level of the recovery position.

In the embodiment illustrated, the ramp 5 comprises two rods 15a (that is metal bars) fixed to the frame 2 and inclined to the supporting surface A at an angle between 5° and 15°, preferably approximately 10°.

These rods 15a are parallel to each other and spaced apart by a space which is smaller than the diameter of the ball 100 (that is less than 6 cm).

Preferably, the pushing member 14 is at least partially defined by a rotating element 16 which is rotatable about an axis of rotation B which is orthogonal to the supporting surface A for the frame 2.

The rotating element is equipped with a shaft 16b which is rotatably associated with the frame 2 of the device 1 , preferably by means of specific bearings 22.

In the embodiment illustrated, the rotating element 16 is driven by a respective drive unit 17.

Preferably, this drive unit is defined by a brushless motor.

Alternatively, the rotating element could be driven by a step-step motor or the like.

This rotating element 16 is equipped with a plurality of radial blades 16a, 16b, 16c angularly spaced from each other so as to successively act on a corresponding succession of balls 100 located on the supporting surface A.

Advantageously, this allows the device 1 to operate continuously and uninterruptedly on a plurality of balls 100 in succession, thanks to the cyclical rotation of the blades 16a, 16b, 16c, one of which is always in a working position for collecting one ball 100.

It should be noted that each blade 16a, 16b, 16c defines a corresponding stop wall 14a. Consequently, the sensitive member 27 is positioned on each blade 16a, 16b, 16c of the rotating element 16.

Preferably, the sensitive member 27 is positioned at a free end of each blade 16a, 16b, 16c.

Preferably, the blades 16a, 16b, 16c of the rotating element 16 are equally angularly spaced from each other.

In the preferred embodiment, the rotating element 16 comprises three blades 16a, 16b, 16c. Consequently, these blades are offset by approximately 120° from each other.

Thus, a circular section is defined between two adjacent blades 16a, 16b, 16c which is large enough to receive one ball 100 inside of it.

In this way, each ball 100 is operatively engaged by a single circular sector (that is between two adjacent blades 16a, 16b, 16c of a single rotating element 16).

It should be noted that the access mouth 10a of the conduit 10 is substantially defined between the axis of rotation B of the rotating element 16 and a portion of conduit 10 facing it (in the direction transversal to an advancing direction C of the frame 2).

In a first embodiment (not illustrated), the access mouth of the conduit is defined on the sides by the rotating element (and by its blades) and by a longitudinal wall extending parallel to the conduit, preferably from the access mouth to the end portion of it.

Contrarily, in the embodiment illustrated, the collecting means 7 comprise two pushing members 12 facing each other and opposed to balancedly act on the ball 100.

More precisely, the rotating elements 16 of the pushing members 14 are side-by-side and define respective circular work areas D (which are substantially tangent to each other) at the access mouth 10a of the conduit 10.

Consequently, the access mouth 10a is defined by the centre-to-centre distance between the axes of rotation of the two rotating elements 16. 1.0

This centre-to-centre distance is approximately the size of two tennis balls (that is 120 mm ± 5 mm).

It should be noted that the two rotating elements 16 rotate in opposite directions so that the respective blades 16a, 16b, 16c act in combination on the ball 100.

Preferably, these rotating elements 16 are movable in a synchronized way.

More precisely, the rotation of the two rotating elements 16 is such that each blade 16a, 16b, 16c of a rotating element 16 is specularly movable to a corresponding blade 16a, 16b, 16c of the other rotating element 16. Advantageously, in this way, the action of the two rotating elements 16 on the ball 100, and in particular of the two blades 16a, 16b, 16c, is balanced, thus facilitating the pushing action of the blades.

In this regard, the control unit 13 is associated with the drive units of the rotating elements 16 to drive them in synchrony.

Alternatively, a transmission could be included which is active between the two rotation shafts 16b of the rotating elements 16 so as to relate the movement of them.

Preferably, the rotation of the two rotating elements 16 occurs by successive steps.

Each rotating element rotates by approximately 120° for each step to bring each blade 16a, 16b, 16c into the angular position of the adjacent blade 16a, 16b, 16c.

It should be noted that the blades 16a, 16b, 16c of the rotating elements 6 define the funnel portion of the conduit 10 described above.

In effect, in the resting configuration of the collecting means 7 each rotating element 16 has a first blade 16a aligned (parallel) to the advancing direction C of the device 1 and parallel to the corresponding first blade 16a of the other rotating element.

Furthermore, in this configuration the rotating elements 16 have respective second blades 16b proximal to the end portion 10b of the conduit 10 with respect to the first blades 16a, which are arranged towards each other and define a funnel or hopper for channelling the ball 100.

Once the rotating elements 16 are driven by the respective drive units, the first blades 16a rotate to the position of the second blades 16b while pushing the ball towards the end portion 10b of the conduit 10 (thus acting as pushing members 14) and occluding the access mouth 10a (thus acting as restraint means 12).

As indicated above, the device 1 (in particular the collecting and storing unit 6) comprises a lifting member 8 associated with said collecting means 7 for receiving the ball 100 and raising the height of it from a lower height Q1 to an upper height Q2.

This lifting member 8 is located at the end portion 10b of the conduit 10. More precisely, the lifting member 8 is positioned so as to collect the ball 100 from its recovery position, that is at the top of the ramp 15.

Preferably, the lifting member 8 comprises a plurality of concave scoops 18 shaped to receive the ball 100 (a single ball 100) inside the concavity. These scoops 18 are cyclically movable to successively reach the recovery position (at the lower height Q1) and lift the ball to the upper height Q2, where they reach a release position of the ball 100.

In the preferred embodiment, the lifting member 8 comprises a disc 19 pivoted on the frame 2, for rotating about an axis of rotation D parallel to the supporting surface A.

This disc 19 comprises a plurality of radial arms 20 having a curved portion 20a (defining one of the scoops 18) so as to each collect a ball 100 located at the end portion 10b of the conduit 10 (that is in the collecting position).

The arms 20 are rigidly fixed to the disc 19 (and made as one with it).

Preferably, the lifting member 8 (and therefore the disc 20) is placed into rotation by a rotational actuator (not illustrated).

Preferably, the actuator is independent from the drive units 17 of the rotating elements 16 and from the moving means 4 of the frame 2. However, a transmission can be provided which directly correlates the rotation of the disc 19 with the movements of other elements of the device 1 (rotating elements 16, moving means 4).

This way, the structure of the device 1 (and the control of it) are advantageously simplified.

Preferably, at the upper height Q2, the device 1 comprises a chute 21 , which is rigidly connected to the frame 2 and extends downwards from the release position to its free end 21a.

This free end 21a is substantially located at the back portion 2b of the frame 2.

In the embodiment illustrated, the chute 21 (similarly to the ramp 15) is also defined by a pair of parallel rods 21b (or bars) spaced apart by a space that is smaller than the diameter of the ball 100 (therefore less than 6 cm).

As already indicated above, in order to accumulate the balls 100 collected, the device 1 (and in particular the collecting and storing unit 6) comprises a container 9 connected to the frame 2 and interposed between the lower height Q1 and the upper height Q2 so as to receive said ball 100 from the lifting member 8 by gravity.

More precisely, the container 9 is located at the back portion 2b of the frame 2 (and facing the free end 21a of the chute 21).

In the embodiment illustrated, the container 9 is a basket 23 measuring approximately 400 mm x 500 mm x 200 mm.

Alternatively, a larger container 9 may be provided, that is, measuring approximately 600 mm x 500 mm x 200 mm.

According to the invention, the frame 2 (and therefore the device 1) is self- propelled.

Therefore, the control unit 13 is associated with the moving means 4 for driving the device 1 along the supporting surface A.

Preferably, the device 1 comprises a detection sensor 24 connected to the frame 2 and configured to detect the presence of one or more balls 00 in a zone of the supporting surface A surrounding the frame 2.

More preferably, this sensor is located at the front portion 2a of the frame

2.

Preferably, the device 1 comprises a pair of detection sensors 24 side-by- side and mounted on the front portion 2a of the frame 2.

These sensors 24 are preferably configured to each define an operating area of it. Preferably, the sensors 24 are positioned so that the respective operating areas define an overlapping (or intersecting) zone located in front of the access mouth 10a.

Preferably, the detection sensor (or sensors) 24 are defined by sonar. Alternatively, the detection sensor 24 is of the ultrasound type.

The ultrasound sensor is extremely compact and is characterized by particularly low energy consumption.

Advantageously, the sensor allows detecting objects at a distance from 0 to 10.68 metres, and providing data on the distance from 20 cm 1068 cm with a resolution of 1 centimetre.

The communication interface is multi-format. The pulse width port can be used or the analogue port, which provides variable voltage based on the distance detected. An asynchronous serial port is also available.

Advantageously, the device 1 is very versatile and innovative thanks to these ultrasound sensor interface modes.

Alternatively, the detection sensor 24 could be infrared or have a video camera or the like.

In this regard, the control unit 13 is associated with the detection sensor 24 and with moving means 4.

In particular, the control unit 13 is designed to receive a signal representing the position of the ball 100 (or of the balls) from the detection sensor 24.

The control unit 13 is also configured to drive the moving means 4 as a function of the signal received.

More precisely, the control unit 13 comprises a processor (not illustrated) programmed to determine which among the balls detected is the easiest ball 100 to reach (or alternatively the area with the highest density of balls 100) and is configured to control (drive) the moving means 4 accordingly. In the preferred embodiment, the detection sensors 24 are each configured to send a signal representing the presence of at least one ball 00 within the respective operating area.

In light of this, the control unit 13 is programmed to receive said signal from the detection sensors 24 and to control the moving means 4 so that the ball detected by at least one of the detection sensors 24 enters the intersection zone of the operating areas.

In other words, if a first detection sensor 24a detects the presence of a ball within its operating area, the control unit 10 sends a signal representing a rotation of the device to the moving means 4 such as to allow the detection of the same ball 100 also by the second detection sensor.

Preferably, the device 1 also comprises means 26 for identifying the white line on the tennis court.

These identifying means 26 are also connected to the control unit 13 to make available a signal representing a crossing of the white line.

The control unit 13 is therefore programmed (in at least one of its functions) to drive the moving means 4 so as to move the device along the white line (in absence of signals from the sensors 24).

Therefore, the control unit 13 is programmed to drive the moving means 4 so as to move the device away from the white line (outside the tennis court) after at least one detection sensor 24 receives a signal representing the presence of a ball 100 in the respective operating area.

It should be noted that when the detection sensors 24 do not detect a ball

100 within their operating area, the control unit 13 is programmed to drive the moving means 4 closer to the white line (the position of which is saved following the last detection of the identifying means 26) until it is reached.

It should be noted that the control unit 13 is configured to receive the ball presence signal (sent by the sensors 24), process it by giving it a priority with respect to the signal representing the crossing of the white line and drive the moving means 4 accordingly.

Preferably, the device 1 also comprises a human presence sensor 25, which is configured to detect the presence of human beings (in particular of the players) near the frame 2.

The human presence sensor 25 can be an infrared sensor, a thermal sensor or others.

This sensor 25 is also operatively associated with the control unit 13 to send it a signal representing the position detected.

The control unit 13 is configured to receive the signal, process it and impart it with a priority with respect to the signal representing the position of the balls 100 (for safety reasons) and drive the moving means 4 accordingly.

The control unit 13 can advantageously be set up by a user in a plurality of operating modes.

In a first mode (net), the control unit 13 only drives the moving means 4 close to the tennis court net.

Advantageously, it is possible in this mode for the players to continue playing (for example, warmup or lesson) from the court baseline without interference.

In a second mode (line), the control unit 13 only drives the moving means 4 outside the tennis court lines (identified by the means 26).

Advantageously, in this mode it is possible for the players to continue playing on the entire court.

In a third operating mode (full), the control unit 13 drives the moving means 4 along the entire court to collect all the balls 100 on it.

It should be noted that in a full optional version, the device 1 comprises collecting members arranged at the front of it and configured to define a hopper shaped to increase the collection capacity of the device.

Preferably, these collecting members are defined by walls which tilt between a resting position, in which they substantially have no volume, and an operating position, in which they define the hopper.

In light of this, the device also comprises a sensor capable of determining its position with respect to the tennis court (for example, by a system of fixed references arranged at the sides of the court, by perimetrical self- learning, a luminescence sensor for identifying lines on the court).

Alternatively, the device 1 can be remotely controlled by a user.

In this embodiment, the device comprises a receiving member (not illustrated) capable of receiving a control signal sent to a transmitter being used by the user.

The device 1 further comprises, on board, one or more rechargeable batteries (not illustrated) connected to the moving means 4, to the restraint means 12 (and to the pushing member 14) and to the lifting member, to power them during movement.

In this regard, the device has a recharging station (not illustrated) that can be positioned at the side of the court and connected to the mains electricity supply.

The control unit 13 is programmed to bring the device 1 back to the recharging station when it is in resting condition.

Advantageously, the device has very high operating performance, considering that it is used for short time intervals, for example between one change of side and another.

Alternatively, solar panels (not illustrated) capable of supplying the device 1 can be used instead of, or in combination with, the batteries.

Advantageously, considering that tennis is for the most part played during the warmer seasons, solar panels might reduce the absorption of energy from the electrical network.

In an alternative more economical embodiment, the device can be connected directly to the mains electricity supply (for example with a wire). Preferably, the device 1 also comprises auxiliary means.

These auxiliary means comprise a sheet (not illustrated) associated with the device to sweep clay or hard tennis courts after the balls 100 have been collected.

This sheet is preferably removable from the frame and can be associated with it only when needed.

In the preferred embodiment, the sheet is connected to the frame 2 by a metal (or plastic) bar rotatably associated with the frame so as to roll or unroll the sheet as a function of the use.

This invention also relates to a tennis ball collecting system.

The system comprises:

- at least one tennis court 200;

- at least one device 1 for collecting balls 100 as in the foregoing description,

- at least one recharging station as in the foregoing description.

According to the invention, the tennis court 200 has rounded edges, so as to facilitate the task of the device 1 in collecting the balls 100.

It should be noted that the word "edge" can mean both the four corners of the court 200 as well as the edges running from one corner to another. Should reference be made to the corners, the rounding is on the horizontal plane (that is on the supporting surface A for the device 1).

Should reference be made to the edges, the rounding is on the vertical plane, and therefore between the supporting surface A for the device 1 and the side walls (or nets) of the court 200.

The invention achieves the preset aims and brings important advantages. In effect, due to the presence of the restraint means, the device according to this invention ensures the collection of all the balls, thus preventing them from escaping.

Furthermore, the pushing member ensures that all the balls captured reach the collecting position at the foot of the lifting member.

Furthermore, the presence of rotating elements equipped with blades ensures that all the balls are collected and guided one-by-one towards the lifting member.

The lifting member, comprising a disc fitted with a pair of scoop-shaped arms, is completely rigid and therefore solid, thus preventing the problems given by chain transmissions or the like.

The presence of the control unit and of the sensors allows the device to move about in complete autonomy, while identifying the zones to be inspected and selecting the balls to be collected.

Furthermore, the use of sensors for detecting human presence increases safety when using the device even when the game is being played.

Claims

1. A ball collecting device, comprising:

- a frame (2);

- moving means (4) associated with the frame (2) for moving said frame (2) along a supporting surface (A) for the frame (2);

- collecting means (7) connected to the frame (2) and configured to collect at least one ball (100) arranged on said supporting surface (A);

- a lifting member (8) associated with said collecting means (7) for receiving said ball (100) and raising the height thereof from a lower height (Q1) to an upper height (Q2);

- a container (9) connected to the frame (2) and interposed between said lower height (Q1) and said upper height (Q2) so as to receive said ball (100) from the lifting member (8) by gravity;

characterized in that the collecting means (7) comprise:

- an inlet conduit (10) with an access mouth (10a) shaped to receive said ball (100) and an end portion (10b) leading to the lifting member (8);

- restraint means (12) configured to at least partially occlude said access mouth (10a) and activatable when said ball (100) is located inside said conduit (10) in order to prevent the escaping thereof.

2. A device according to claim 1 , characterized in that the collecting means (7) comprise at least one pushing member (14) which is operatively active inside said conduit (10) between the access mouth (10a) and the end portion (10b) thereof to guide the ball ( 0) towards the lifting member (8).

3. A device according to claim 2, characterized in that the pushing member (14) at least partially defines the restraint means (12).

4. A device according to claim 2 or 3, characterized in that the pushing member (14) comprises at least one stop wall (14a) which is movable along the conduit (10).

5. A device according to claim 4, characterized in that the pushing member (14) is at least partially defined by a rotating element (16) which is rotatable about an axis of rotation (B) orthogonal to said supporting surface (A) of the frame (2), and equipped with a plurality of radial blades (16a, 16b, 16c) angularly spaced from each other so as to continuously act on a plurality of balls (100) arranged in succession on the supporting surface (A); each blade (16a, 16b, 16c) defining a stop wall (14a).

6. A device according to claim 5, characterized in that the rotating element (16) comprises three blades (16a, 16b, 16c) which are equally angularly spaced from each other.

7. A device according to any one of the claims from 2 to 6, characterized in that the collecting means (7) comprise two pushing members (14) facing each other and opposed to balancedly act on each ball (100).

8. A device according to claim 6, characterized in that the rotating elements (16) of the pushing members (14) are side-by-side and define respective circular work areas which are substantially tangent to each other at the access mouth (10a) of the conduit (10).

9. A device according to any one of the preceding claims, characterized in that the lifting member (8) comprises a disc (19) pivoted on the frame (2), for rotating about an axis of rotation (D) parallel to the supporting surface (A) and comprising a plurality of radial arms (20) having a recurved portion (20a) shaped to collect a ball (100) located at the end portion (10b) of the conduit (10).

10. A device according to any one of the preceding claims, characterized in that it comprises:

- at least one sensor (24) for detecting the presence of one or more balls (100) in a zone of the supporting surface (A) surrounding the frame (2);

- a control unit (13) associated with the moving means and with said at least one detection sensor (24), set up to receive a signal from the detection sensor and configured to drive the moving means (4) according to said signal.

11. A device according to claim 10, characterized in that it comprises a pair of detection sensors (24) side-by-side and arranged on a front portion (2a) of the frame (2), each defining its operating area; said detection sensors (24) being positioned so that the respective operating areas define a superposing zone located at the access mouth (10a).

12. A device according to claim 11 , characterized in that the control unit (13) is programmed to receive the signal from the detection sensors (24) and to control the moving means (4) so that the ball (100) detected by at least one of the detection sensors (24) enters the intersection zone of the operating areas.

13. A device according to any one of the claims from 10 to 12, characterized in that it comprises means (26) for identifying the white line on the tennis court, which are connected to the control unit (13) to make a signal representing the white line being crossed available to said control unit (13).

14. A device according to claim 13, characterized in that said control unit (13) is therefore programmed to drive the moving means (4) so as to move the device along the white line.

15. A device according to claim 14, characterized in that said control unit (13) is programmed to drive the moving means (4) so as to move the device away from the white line, outside the tennis court, after at least one detection sensor receives a signal representing the presence of a ball (100) in the respective operating area.

16. A device according to any one of the preceding claims, characterized in that it comprises a ramp (15) located inside the conduit, for bringing the ball (100) from a first height, where it is in contact with the supporting surface (A), to a second height corresponding to said lower height (Q1), where the ball is engageable by the lifting member (8) without said lifting member (8) coming into contact with the supporting surface (A).