This invention relates to concealed sports-action cameras and mounting mechanisms therefor.

BACKGROUND

In televised sporting events, miniature cameras are increasingly employed to capture interesting views and angles of the action. Video cameras can be provided within sporting field fixtures to provide television viewers with an on field perspective of the match or game being broadcast. For example, in the game of cricket it is known for a camera to be positioned within a cricket stump at the batsman's end of the cricket pitch. Such cameras provide viewers with a unique and close up view of the action occurring on the cricket pitch, particularly when a batsman is bowled, thereby enhancing the viewer's experience of the cricket match. The purpose of cricket stumps is to support bails that are to be dislodged upon impact with the cricket ball or wicketkeepers gloves, for example. Impact from a cricket ball, in particular, can be quite violent. When the stumps are disturbed in this way, a camera concealed therein can become misaligned whereby the camera field of view is inappropriate for television broadcast. This may be exacerbated by current camera mounting arrangements and practices in which technicians use ad hoc shims and the like, wedged into the camera mount to achieve a desired vertical alignment of the camera. It is not uncommon for such mounting arrangements to permit misalignment of the camera following an impact with the stumps, requiring attendance of a technician to rectify it. Since the stumps and camera are in the field of play, however, sometimes there can be an extended delay until the technician is allowed to fix the camera alignment. This can mean that the camera is unusable in the meantime, and therefore may be underutilised during the broadcast.

Any discussion of documents, devices, acts or knowledge in this specification is included to explain the context of the invention. It should not be taken as an admission that any of the material forms part of the prior art base or common general knowledge in the relevant art in Australia or elsewhere on or before the priority date of the disclosure and claims herein. In view of the foregoing, the inventor has realised that it would be desirable to provide an improved camera system and mounting mechanism suitable to be concealed within a cricket stump. Although the invention is predominantly described in the context of the sport of cricket, it should be understood that the camera system and mounting mechanism is not necessarily limited to that application only.

SUMMARY

In accordance with the present invention there is provided a mounting mechanism for sports- action camera system having a camera for capturing video images coupled to a mounting plate, the mounting plate being pivotally supported by a housing for tilt adjustment of the mounting plate and camera relative to the housing. Preferably the housing is adapted for concealment within a sports equipment fixture, such as a cricket stump, goal-post or the like.

In one form of the invention the mounting plate is supported by the housing by means of a pivot pin. The mounting mechanism may also include a bias spring acting between the housing and the mounting plate, and an adjustment screw acting between the housing and the mounting plate to enable user adjustment of the mounting plate tilt angle. In one form of the invention the pivot pin is, in use, oriented horizontally such that user adjustment of the tilt angle by way of the adjustment screw affects the vertical view angle of the camera.

In the context of this disclosure, where reference is made to 'concealing' the camera and/or mounting mechanism in a sports equipment fixture this does not necessarily mean that the camera and/or mounting mechanism is entirely hidden or completely undetectable, but merely that the camera and/or mounting mechanism is contained so as not to alter the fundamental function of the sports equipment fixture. For example, where the camera is concealed within a cricket stump, the stump containing camera should still maintain its regulation external dimensions of height and exterior diameter.

In the context of this disclosure, where reference is made to a 'mounting plate' this should not be taken to necessarily impart upon that component any or all 'plate-like' characteristics or dimensions; in other words, a mounting plate as referred to herein may not necessarily be flat, round or thin as, for example, a dinner plate. In accordance with another aspect of the present invention, there is provided a sports-action camera attached to a mounting plate which is pivotally supported within a housing structure, including an adjustment screw means and a spring bias means acting between the housing structure and mounting plate to facilitate tilt adjustment of the mounting plate relative to the housing structure, wherein the housing structure is adapted for concealment within a sports equipment fixture.

In one form of the invention the housing structure is adapted for insertion within a hollow cricket- stump. Other forms of sports equipment fixture that sports action camera may be concealed in include goal-posts and the like as used in AFL football, soccer, hockey, ice-hockey, etc. The camera system and mounting mechanism is designed to enable accurate and reliable adjustment of the camera's vertical tilt to obtain a desired field of view, and to maintain the desired field of view following impact upon the sports equipment fixture as may occur during sports play. Other reliability issues for such a camera system that may arise from impact in use are also addressed.

BRIEF DESCRIPTION OF THE DRAWINGS

Further disclosure, objects, advantages and aspects of the present invention may be better understood by those skilled in the relevant art by reference to the following description of preferred embodiments taken in conjunction with the accompanying drawings, which are given by way of illustration only and thus not limitative of the present invention, and in which:

Figure 1 is a central cross-sectional diagram of the upper portion of a cricket stump incorporating a camera and mounting mechanism according to an embodiment of the present invention;

Figures 2A and 2B illustrate the camera and primary mounting mechanism components in a disassembled condition;

Figure 3 illustrates the camera and mounting mechanism components in a partially assembled condition;

Figures 4A and 4B illustrate the camera assembled with the mounting mechanism before being mounted in a cricket stump; Figure 5 illustrates the camera and mounting mechanism in the process of insertion into a cricket stump;

Figure 6A shows orthogonal and sectional views of the camera and mounting mechanism mounted within a section of a cricket stump;

Figure 6B is a diagrammatic illustration of a modified cricket stump construction including a split-manifold for heated exhaust air egress;

Figures 7A-7D are front and sectional side views of a camera focus adjustment tool; and Figures 8A and 8B illustrate the camera focus adjustment tool engaged with a camera lens.

DETAILED DESCRIPTION

A sports-action camera system and mounting mechanism is described hereinbelow, particularly adapted for concealment in a cricket stump. The mounting mechanism is designed to address prior art issues of not having a reliable means of maintaining the vertical horizon setting of the camera after the stump has been impacted by the ball during the course of the game, and not having a fine precision vertical adjustment mechanism for the camera installed in the stump.

In the following description, where directional terms are used such as 'top', 'bottom', 'above' and 'below', these are understood to be with reference to the cricket stump when in place for use on a cricket pitch. Terms such as 'front', 'rear', 'sideways' and the like are made with reference to the direction in which the camera faces, which is typically aligned with the direction of extent of the cricket pitch.

When converted to metric dimensions, a regulation cricket stump is 711 mm tall, and between 35 mm and 38 mm in external diameter. Although traditional cricket stumps are formed from timber, modern-day stumps can be constructed from tubular metal, plastic, fibre-glass or other synthetic materials which are more durable. As is known, the hollow tubular stumps permit installation of devices therein such as microphones and cameras that can be used to enhance broadcast television coverage, and even be used in umpiring review decisions. Presently used stump-camera mounting arrangements can have a tendency to lose their vertical field-of-view alignment following an impact on the stumps, which may negatively affect vision from the camera until attended to by a technician. However, the technician may not have access to the stump-camera until a subsequent break in play, such as a drinks break, which could delay the camera realignment by up to an hour or more. These circumstances can result in underutilisation of the stump-camera footage by television broadcasters, and also negatively impact the use of stump-camera vision in umpiring decision reviews. With these factors in mind, it is desirable for a stump-camera and its mounting arrangement to be robust in order to withstand impacts on the stump as may be expected during a cricket game, and to be readily an accurately adjustable with respect to the camera's vertical field-of-view.

A stump-camera system and mounting mechanism according to an embodiment of the present invention is illustrated in various views in Figures 1 to 5. The camera and mounting mechanism are particularly adapted for installation within the hollow interior of a cricket stump 10 having tubular wall construction. In order to permit the camera lens a view of the cricket pitch the stump has a viewing aperture 14 formed therein, seen best in the cross- sectional view of Figure 1. Just below the viewing aperture is an adjustment screw access hole 12 allowing access to an adjustment screw 28. To enable the camera lens to face the cricket pitch when the stump is in situ, the viewing aperture 14 is formed in the tubular wall of the stump so that the optical axis of the camera is transverse to the axis of the bail groove 16 on top of the stump (Figure 1).

The camera system 50 includes an imaging sensor 51 with a lens optical element 52, and may also include associated circuitry 54 coupled to the sensor by cable 56. The lens optical element is affixed within a lens barrel 53 which is mounted in relation to the imaging sensor such that light passing through the optical element 52 can be focussed upon the imaging sensor. The camera system is adapted for generating high-definition video signals representing images viewed through the lens 52, and conveying the video signals by way of wired or wireless transmission to a television editing and broadcast system, for example. The camera system is small enough to be concealed within the stump, and may be selected from amongst a number of suitable commercially available models from various manufacturers.

In use the camera system 50 is mounted to a mounting mechanism 60 that is removably installed inside the stump 10. The primary individual components of the mounting mechanism 60 are best seen in Figures 2A and 2B where they are shown in a disassembled condition. The primary components include a mounting capsule housing 20 and mounting plate 30. The mounting capsule housing 20 has a generally cylindrical exterior form, although portions may be cut-away as seen in the Figures for airflow and ease of access to the camera system in use. The exterior diameter of the capsule housing is marginally smaller than the interior diameter of the hollow stump so the capsule housing with camera system can be inserted into the stump as described further below. The capsule housing has a lens accommodating aperture 22 that in use aligns with the aperture 14 in the tubular wall of the stump. As shown in Figure 1, the capsule housing 20 may be held in place in relation to the stump 10 by means of mounting screws or bolts 11.

In the embodiments illustrated herein, the mounting plate 30 is in use securely fastened to the camera 50 by screws or bolts 34 that attach to sides of the camera sensor structure, although it is envisaged that the mounting plate could in fact be unitary with the camera structure rather than an additional component. When so attached the lens barrel containing the camera lens 52 projects through an aperture 32 of the mounting plate, as seen in Figure 3. The mounting plate 30 has a lateral hole 36 that extends therethrough, just above the camera lens aperture 32. The hole 36 is designed to fit a pivot pin 40, the ends of which protrude outside the mounting plate for engagement with holes 24 formed in side walls of the capsule housing.

The overall mechanical system of components is such that the capsule housing 20 is in use immovably fixed inside the cricket stump, and the camera affixed to the mounting plate 30 is pivotally supported in the capsule housing by the pin 40. The pivot pin 40 extends horizontally transverse of the camera optical axis which permits pivoting adjustment of the mounting plate and camera relative to the stump. The means for effecting such adjustments are described hereinbelow. A compression spring 42 is positioned between the front of the mounting plate and the inside of the capsule housing to provide to provide a spring bias therebetween. A first spring locating depression 38 is formed in the mounting plate 30 above the pivot pin axis for seating one end of the spring 42, and a second locating depression 26 is formed in a corresponding locating in the capsule housing 20 for seating the other end of the spring. The relative locations of the spring 42 and pivot pin 40 can be seen where these components are assembled in the capsule housing 20 in Figure 3. Below the capsule housing lens aperture 22 is an adjustment screw 28. The adjustment screw has a screw-threaded engagement through the front of the capsule housing so that the head is, in use, accessible through the access hole 12 (Figure 1). The end of the adjustment screw 28 extends into the capsule housing, as seen in Figures 1, 2 and 3, to in use bear upon the lower end of the mounting plate 30. Since the adjustment screw 28 and bias spring 42 are disposed to opposite ends of mounting plate 30 with respect to the axis of the pivot pin 40, the screw and spring act against one another to enable an amount of pivotal adjustment of the mounting plate. By screwing the adjustment screw 28 into the capsule housing the mounting plate 30 can be made to pivot about the pin 40, against the spring bias force, so as to tilt the camera axis downward. Conversely, by adjusting the screw 28 in the other direction the bias spring 42 acts upon the mounting plate 30 so that the camera tilts upward. The described mechanism thus allows for adjustment of the camera view in the vertical dimension across a range of optical alignments as indicated at 45 in Figure 1. The screw 28 may preferably incorporate a spring loaded bearing at its end that bears against the mounting plate.

Assembly of the camera and mounting mechanism may be accomplished as described below. First the camera is attached to the mounting plate 30 by engagement of the screws 34 through the mounting plate to the camera sensor board 50. When so attached, the lens barrel 53 camera lens 52 projects through the central aperture 32 of the mounting plate with the lateral hole 36 located 'above' the lens. Then, the camera with attached mounting plate is located into the capsule housing 20 with the camera lens 52 facing out of the housing aperture 22. The components 54, 56 associated with the camera are arranged within the space provided in the capsule housing 20 'below' the camera lens. The spring 42 is then positioned between the mounting plate and capsule housing, with its ends located in the respective locating depressions 38, 26. Then, the mounting plate is held in a position in which the lateral hole 36 is aligned with holes 24 in the capsule housing side walls, and the pivot pin is inserted from one of the holes 24, through the mounting plate and into engagement with the hole 24 on the other side of the capsule housing. With the adjustment screw 28 engaged in its hole in the front of the housing below the lens, the mounting mechanism and camera system then resembles the illustration shown in Figures 4A and 4B. To complete the installation procedure the capsule housing is then inserted into the hollow interior of the cricket stump 10 as shown in Figure 5. The capsule housing is inserted to a point where the camera lens 52 is aligned with the corresponding aperture 14 formed in the stump wall, and the adjustment screw head is accessible through its corresponding aperture 12 (see Figure 1), whereupon the capsule housing may be secured to the stump with bolts 11.

The components of the mechanism can be constructed from any durable, preferably lightweight, material, such as aluminium alloys. There are many variations to the spring action and how it can be arranged around the pivot point in the camera mount pivot plate. Any kind of spring may be used acting in various different arrangements against the adjusting screw. Using any combination of spring arrangements, compression spring, tension spring and torque spring either individually or combined may be employed. Moreover, the spring may be set up on the same side of the pivot point action, acting against the adjustment screw, or on the opposite side of the pivot point acting against the adjusting screw, or the spring may be arranged to act around the pivot point against the screw or to assist the screw function. There may in fact be a combination of springs either acting against and or assisting the adjustment screw. In the preferred construction of the mounting mechanism, a spring loaded ball is provided in the end of the adjusting screw acting between the screw and the camera mount pivot plate. This may act as an impact buffer to assist the integrity of the camera and help maintain pre-impact vertical settings to the horizon of the camera. Another factor that can affect the reliability of a camera installation of the type described herein is communications cable connectors, which may be knocked loose when an impact occurs. For example, a data and power ribbon cable 56 interconnects the camera sensor and drive circuitry board 54, and a data and power cable 58 is coupled to external apparatus to convey electrical power and data to and from the drive circuitry board. The cable 56 couples to the camera at a plug interface 59 (Figure 1), and to prevent the plug interface 59 from inadvertently being disconnected in an impact, an L-shaped support clamp 31 is provided, attached to the rear of the mounting plate 30 with a lip that extends over the plug interface 59. A rubber boot or thin layer of elastomeric material may be interposed between the plug interface and support clamp for protection. Similarly, the other end of the cable 56 where it couples to the drive circuitry board 54 has a plug interface that is mounted closely to a portion of the capsule housing to prevent the plug interface becoming accidently dislodged. Another clamp 57 (Figure 4A, Figure 5) may be provided to for the same purpose in relation to the coupling of cable 58. Another aspect that has been taken into consideration in development of the disclosed concealed camera system and mounting mechanism is the issue of heat dissipation. It will be appreciated that the camera system, like all electronic systems, generates heat during operation and, being confined within an enclosed space, if the heat is not managed the temperature may increase excessively. This issue may be particularly acute where two cameras are mounting in a single stump. Accordingly, the camera mounting arrangement has been designed to assist in heat dissipation when installed with the confines of a cricket stump, for example. Specifically, the mounting mechanism design allows for airflow vertically through the hollow interior of the cricket stump, through the mounting mechanism capsule housing. This is the reason why the capsule housing 20 is open at the top and bottom and provides open space for airflow over the electronic circuitry 54 which generates the most heat. Moreover, if the capsule housing 20 is formed from aluminium, for example, it is able to act as a heat sink with increased surface area for heat dissipation. If necessary, one or more fans can be incorporated into the system, for example mounted to the capsule housing at the top or bottom to draw air through the hollow interior of the stump. To assist in heat extraction airflow it may be desirable for the stump to also include apertures toward the bottom and top for air intake and exhaust. These aspects are discussed in greater detail below. Since the camera and associated circuitry is mounted in a confined space, heat generated by the electrical components may build up within the interior of the stump, which can also cause difficulties. The camera and mounting system according to embodiments of the invention is therefore designed and constructed with a ventilation system. This includes a small exhaust fan 70 shown diagrammatically in Figure 1 mounted to the top of the capsule housing 20. The fan 70 is arranged to expel heated air generated by the camera system upwards, thereby drawing cooler air from below. The camera and mounting system has airflow channels adapted for this purpose and indicated at 75 in the top and bottom end views seen in Figure 6A. To assist in exhausting the hot air from the stump, the top of the stump may be provided with an air diffuser manifold 80 which is diagrammatically illustrated in Figure 6B in side -sectional and end views. The air diffuser manifold has a central divider 82 within the hollow stump that splits the upward airflow into two tapered channels 84 to be exhausted through two or more exhaust holes 86. This construction prevents the hot air from generating a vortex effect at the top of the hollow interior and assists in more effectively extracting heat.

Sometimes in use of the camera it is necessary to adjust the camera focus. In order to do so, the lens barrel is mounted to the camera by a screw thread such that rotating the lens barrel alters the focus. Once the correct focus is achieved, a screw threaded locking ring may be tightened to maintain the setting. With the camera mounted inside a cricket stump, for example, it is not easy to accomplish the focus adjustment, and accordingly a focus adjusting tool 90 has been developed, which is illustrated in various views in Figures 7 and 8. The tool 90 has a circular flange 91 that defines a central lens aperture 92. The lower portion of the flange 91 is provided with a snap-fit seat 93 having a semi-circular ridge 94 that fits over the rear of the camera barrel end. In use, the tool can be fitted onto the end of the lens barrel 53 with the snap-fit seat securing the tool around the lens barrel as seen in Figures 7 A, 7D and 8B. The front of the tool 90 has a frustoconical projection 95 with a rim that can be readily manipulated by a user to rotate the lens barrel which is gripped by the circular flange 91 and snap-fit seat. Moreover, whilst the tool is being manipulated to adjust focus, the camera lens is still able to view through the open frustoconical portion of the tool. Apertures 96 are provided to allow access to the locking ring when correct focus has been achieved. Whilst the description above relates to a stump-camera facing along the cricket pitch (i.e. toward the direction of from which the ball is delivered, in some circumstances it is also desirable to have a camera directed in the opposite orientation (i.e. with a view of the wicket-keeper behind the stumps). With that in mind, it is possible for a stump to accommodate two separate cameras, one above the other and facing in opposite directions. In that case each camera would have its own mounting mechanism so that they are individually adjustable.

Although the described embodiment has been in the context of a camera to be concealed in a cricket stump, it may be appreciated that alternative applications in other sports are also possible. For example, it may be desirable to use a similar camera system and/or mounting mechanism for concealing a sports-action camera in a goal-post or goal-upright as used in AFL football, soccer, hockey, ice-hockey, handball, indoor soccer, or indeed within sports equipment fixtures used in other games such as volleyball, tennis, etc. Although some modification may be required to the mechanical arrangement of components, the same principles as described herein could also be used to create a concealed camera system and/or mounting mechanism suitable for horizontally disposed sports equipment fixtures such as goal cross-bars as may be found in rugby, soccer, hockey, etc.

The structure and implementation of embodiments of the invention has been described by way of non-limiting example only, and many additional modifications and variations may be apparent to those skilled in the relevant art without departing from the spirit and scope of the invention described.

Throughout this specification and the claims which follow, unless the context requires otherwise, the word "comprise", and variations such as "comprises" and "comprising", will be understood to imply the inclusion of a stated integer or step or group of integers or steps but not the exclusion of any other integer or step or group of integers or steps.