AU2012258284B2 - A Clutch Mechanism - Google Patents

Abstract

The invention is directed to a clutch mechanism for a barrier operator, the barrier operator comprising a motor, a barrier drive for engaging with a barrier such that 5 rotation of the barrier drive moves the barrier, the clutch mechanism being configured to transfer drive from the motor to the barrier drive, the clutch mechanism comprising a rotatable member driven for rotation by the motor, at least one engagement member movable between an engaged position and a disengaged position, wherein in the engaged position the at least one engagement member is in engagement with the barrier 10 drive, and in the disengaged position the at least one engagement member is out of engagement with the barrier drive, wherein when the at least one engagement member is in the engagement position and engaged with the rotatable member, the operation of the motor causes rotation of the rotatable member and rotation of the barrier drive, and wherein when the at least one engagement member is in the disengaged position, 15 operation of the motor causes rotation of the rotatable member without causing rotation of the barrier drive, whereby manual operation of the barrier is permitted when the at least one engagement member is in the disengaged position.

Description

1 2012258284 22 Feb 2017 A CLUTCH MECHANISM Technical Field

The invention described herein broadly relates to a clutch mechanism. In particular, the invention is directed to a clutch mechanism for a barrier operator.

Background Art 5 In many barrier operators, such as operators for garage doors, a motor is connected to a drive shaft and the drive shaft drives the movement of the barrier. In some situations, for example, in the event of a power outage, it is necessary to disconnect the motor from the barrier so that the barrier can be moved manually, to be able to open and/or close that barrier independently from the motor. 10 Some known barrier operators have a clutch mechanism which comprises a lever. The lever is used to displace the motor to shift it in and out of engagement with the drive shaft. In these barrier operators, the drive shaft is permanently engaged with the barrier. When the motor is shifted out of the engagement with the drive shaft, the barrier can be moved independently of the motor. 15 A major disadvantage of such barrier operators is that a large amount of space is required to shift the motor into and out of engagement with the drive shaft. In some applications, such as barrier operators for roller doors in small garages or workshops, there may not be enough room for a bulky barrier operator.

Further, bulky barrier operators are generally not aesthetically pleasing. 20 Therefore, it is desirable to have a barrier operator which can be used in a small space, for example adjacent or within the drum of a roller door.

It is an aim of the invention to provide a clutch mechanism which overcomes or ameliorates one or more of the disadvantages or problems described above, or which at least provides the consumer with a useful choice. 25

Summary of the Invention

According to a first aspect of the invention, there is provided a clutch mechanism for a barrier operator, the barrier operator comprising a motor, 30 a barrier drive for engaging with a barrier such that rotation of the barrier drive moves the barrier, 2 2012258284 22 Feb 2017 the clutch mechanism being configured to transfer drive from the motor to the barrier drive, the clutch mechanism comprising a rotatable member driven for rotation by the motor, at least one engagement member movable between an engaged position and a 5 disengaged position, the at least one engagement member including one or more projections configured to be inserted into the barrier drive for engagement therewith, the barrier drive defining or having one or more corresponding openings to receive the one or more projections of the at least one engagement member when the at least one engagement member is in the engaged position, the rotatable member defining or 10 having one or more corresponding openings to receive the one or more projections of the at least one engagement member such that rotation of the rotatable member causes rotation of the at least one engagement member at all times, wherein in the engaged position the at least one engagement member isone or more projections extend into the corresponding one or more openings of the barrier drive in 15 engagement with the barrier drive, and in the disengaged position the at least one engagement member isone or more projections are retracted from the openings of the barrier drive and out of engagement with the barrier drive, wherein the rotatable member defines one or more corresponding openings to receive the one or more projections of the at least one engagement member such that 20 rotation of the rotatable member causes rotation of the at least one engagement member at all timeswherein when the at least one engagement member is in the engaged position and engaged with the rotatable member, the operation of the motor causes rotation of the rotatable member and rotation of the barrier drive, and wherein when the at least one engagement member is in the disengaged position, 25 operation of the motor causes rotation of the rotatable member without causing rotation of the barrier drive, whereby manual operation of the barrier is permitted when the at least one engagement member is in the disengaged position. According to a second aspect of the invention, there is provided an operator for a barrier comprising a motor, a barrier drive 30 for engaging with the barrier such that rotation of the barrier drive moves the barrier, a drive train for transferring drive from the motor to the barrier drive, the drive train comprising a clutch mechanism as described herein.

The barrier may have a drum and the operator for the barrier may have a radial extent that is smaller than a radio extent of the drum of the barrier. Preferably, the 3 2012258284 22 Feb 2017 operator is able to be fitted within the interior of the drum of the barrier. More preferably, all components of the operator are fitted within the drum of the barrier.

In one embodiment, the operator may have an outer housing, the outer housing having a radial extent less than the radial extent of the drum. The outer housing may 5 comprise one or more parts. All components of the operator, including the motor, transformer, clutch and logic control board, may be fitted within the housing.

The at least one engagement member may be of any suitable shape, size or form. For example, the at least one engagement member may have one or more projections which are inserted into the barrier drive for engagement therewith. The barrier drive 10 may define one or more corresponding openings to receive the one or more projections of the at least one engagement member. Typically, components of the drive train will maintain engagement with the motor at all times and when the at least one engagement member becomes engaged with the barrier drive, the motor drives and moves the barrier drive. 15 The projections may be of any suitable shape, size or form. For example, the projections may be one or more finger portions and/or the projections may be extendable and retractable. The cross section of the projections may be square, rectangular, circular, oval, triangular, etc.

The projections may be placed on any suitable location on the at least one 20 engagement member. Preferably, the projections are equally spaced around the perimeter of the at least one engagement member.

In a preferred embodiment, the motor drives a drive gear and the rotatable member has a ring gear portion configured for engagement with the drive gear. The rotatable member may maintain engagement with the at least one engagement member 25 at all times.

In one embodiment of the invention, the clutch mechanism comprises a control member. When the control member is moved in a first direction, the at least one engagement member is allowed to move into engagement with the barrier drive. In this engaged position, the barrier drive is engaged with the drive gear via the clutch 30 mechanism, and movement of the motor is transmitted to movement of the barrier drive. The barrier drive then drives a barrier. When the control member is moved in a second direction, the control member allows the at least one engagement member to withdraw from engagement with the barrier drive. In this disengaged position, the barrier drive can be moved manually and independently from the motor. 4 2012258284 22 Feb 2017

In an alternative embodiment, the at least one engagement member can be directly driven by the motor via the drive gear. In this embodiment, the at least one engagement member may have a plurality of teeth configured for engagement with a drive gear associated with the motor. 5 In one embodiment, the clutch mechanism comprises a back-plate and a fixed member rigidly fixed to the back-plate. The control member may be moved in the first and second directions to vary an effective separation distance between the control member and the fixed member to allow the at least one engagement member to move in and out of engagement with the barrier drive. 10 For example, the control member can be moved in the first direction to reduce the separation distance between the fixed member and the control member, and increase the separation distance between the control member and the back-plate to allow the at least one engagement member to be moved into engagement with the barrier drive. When the control is moved in a second direction, the separation distance between the 15 fixed member and the control member is increased, and the separation distance between the control member and the back-plate is reduced. The movement of the control member in the second direction pulls the at least one engagement member towards the back-plate and out of engagement with the barrier drive.

In one embodiment, the control member may have a first set of recesses and a 20 second set of recesses, the first set of recesses being deeper than the second set of recesses. The fixed member may have a plurality of projections having the same shape and size. When the control member is rotated in the first direction, the projections of the fixed member are received in the first set of recesses. When the control member is rotated in the second direction, the projections of the fixed member are received in the 25 second set of recesses. As the second set of recesses are shallower than the first set of recesses, the separation distance between the fixed member and the control member is increased when the projections are moved from the first set of recesses into the second set of recesses. Consequently, the increase in separation distance between the fixed member and the control member moves the control member closer to the back-plate. 30 The movement of the control member closer to the back-plate moves the at least one engagement member out of engagement with the barrier drive.

In an alternative embodiment, the control member may move in one direction to change from the engaged position to the disengaged position and move further in the same direction to change from the disengaged position to the engaged position. The 5 2012258284 22 Feb 2017 control member may be rotated in the same direction between engaged and disengaged positions.

In another alternative embodiment, the control member may have a plurality of projections having the same shape and size, and the fixed member may have a first and 5 second set of recesses having different depth.

The control member may have one or more arms for engagement with the at least one engagement member. When the control member is rotated in a second direction, the one or more arms move the at least one engagement member towards the back-plate as the control member is moved closer to the back-plate, thereby 10 withdrawing the at least one engagement member from engagement with the barrier drive.

In one embodiment, the clutch mechanism may comprise one or more retaining members for retaining the at least one engagement member. The control member may engage with the one or more retaining members to move the at least one engagement 15 member in and out of engagement with the barrier drive.

Preferably, the clutch mechanism has a first retaining member and a second retaining member. The at least one engagement member may be sandwiched between the first retaining member and the second retaining member. The control member may engage with the at least one engagement member through contact with the first retaining 20 member.

Preferably, the clutch mechanism or drive train comprises biasing means. The biasing means may be fitted between the back-plate and the engagement member. Preferably, the biasing means is fitted between the back-plate and the first retaining member. When the control member is moved in the first direction, the biasing means 25 move the at least one engagement member away from the back plate and into engagement with the barrier drive to enable engagement between the barrier drive and the motor. When the control member is moved in the second direction, the control member moves the engagement member closer to the back-plate, thereby compressing the biasing means. 30 In the event that the apertures in the barrier drive do not align with the orientation of the one or more projections of the at least one engagement member, for example after the barrier drive has been manually moved, the biasing means may move the at least one engagement member so that the one or more projections are immediately inserted into the corresponding openings of the barrier drive as the one or more 6 2012258284 22 Feb 2017 projections are moved into alignment with the corresponding apertures by the rotatable member. A person skilled in the art would understand that any suitable biasing means may be used and the biasing means may be of any suitable size, shape or form. For 5 example, the biasing means may comprise one or more helical or coil springs, flat or leaf springs, volute springs, or the like.

To ensure alignment of the components in the clutch mechanism, the clutch mechanism may comprise an axle around which the components in the clutch mechanism may be located. The axle may extend from the back-plate. Typically, the 10 clutch mechanism comprises a base mount which provides the axle through an opening in the back-plate.

The base mount may define a recessed portion to allow movement of the control member. The base mount may define an opening to allow movement of the control member. 15 Typically, the rotatable member is permanently engaged with the drive gear via a ring gear portion. The ring gear portion may form part of the rotatable member. The rotatable member may have an annular rim which defines the body of the ring gear portion. Preferably, the ring gear portion has a plurality of teeth which is disposed on an inner side of the annular rim. It will also be understood that the ring gear may comprise 20 external teeth.

In one embodiment, the rotatable member and the back-plate form an enclosure which holds the other components of the clutch mechanism. The drive gear associated with the motor is disposed adjacent the back-plate. Typically, the drive gear has teeth configured for engagement with the teeth of the ring gear portion on the rotatable 25 member.

The rotatable member may have one or more apertures for receiving the one or more projections of the at least one engagement member. As mentioned, the barrier drive may have matching openings to receive the one or more projections of the at least one engagement member when the at least one engagement member is moved into the 30 engaged position.

The apertures and openings on the rotatable member and the barrier drive may be in any suitable location with respect to the rotatable member and the barrier drive, and the openings may be of any suitable size, shape or form to correspond with the projections of the at least one engagement member. 7 2012258284 22 Feb 2017

For example, the apertures and openings may be circular, square, rectangular or irregular shaped. The openings may be equally or randomly spaced around a portion of the rotatable member and the barrier drive. In one embodiment, eyelets may be equally spaced in a circular arrangement on the rotatable member and the barrier drive to 5 receive the projections of the at least one engagement member.

Typically, the projections in the at least one engagement member are seated within the apertures of the rotatable member at all times, i.e. irrespective of whether the at least one engagement member is in the engaged position or the disengaged position. When the control member is rotated in the first direction, the at least one engagement 10 member is moved towards the rotatable member by the biasing means. At the same time, the projections on the at least one engagement member are inserted into the corresponding openings of the barrier drive. In this engaged position, when the motor is activated, the drive gear rotates the rotatable member by turning the ring gear portion. As the projections are inserted through the corresponding openings in the rotatable 15 member and the barrier drive, the rotation of the rotatable member is transferred through the projections to the barrier drive. In this manner, the rotation of the motor is transmitted to the barrier drive. When the control member is rotated in the second direction, the control member moves the at least one engagement member back towards the back plate. In this position, the projections of the at least one engagement member 20 are withdrawn from the corresponding openings in the barrier drive and the barrier drive is no longer engaged with the drive gear and motor through the projections and the rotatable member. In the disengaged position, the barrier drive can be moved independently from the motor.

One advantage of having the projections received in the openings of the 25 rotatable member at all times is that the space occupied by the components of the drive train is minimized. This also ensures that the projections remain in alignment with the respective openings in the rotatable member.

Preferably, an operating member is connected to the control member. The operating member may be moved between an activated position and a deactivated 30 position. The movement of the operating member between the activated position and the deactivated position moves the control member in the first and second directions. Typically, in the activated position, the motor engages the barrier drive, and in the deactivated position, the motor is disengaged from the barrier drive. 8 2012258284 22 Feb 2017

The operating member may be moved automatically or manually. Typically, the operating member is moved manually by a user.

The operating member may be of any suitable shape, size or form. For example, the operating member may be a rope, a rod, a switch, a button, a lever, a pull cord, a 5 knob, or the like. A person skilled in the art would understand that the clutch mechanism may be used in any suitable application. Preferably, the clutch mechanism is used on a barrier operator for a garage door. When the motor is engaged with the barrier drive, the garage door can be moved automatically by turning on the motor. When the motor is 10 disengaged with the barrier drive, the garage door is effectively disconnected from the motor and can be moved manually without affecting the motor.

According to a third aspect of the invention, there is provided an operator for a barrier, wherein the operator has a radial extent that is less than a radial extent of a drum of the barrier. 15 Typically, the operator is sized to be able to fit within an interior of the drum of the barrier.

Preferably, the operator has an outer housing, the outer housing having a radial extent that is less than the radial extent of the drum of the barrier. Typically, the outer housing contains all components of the operator such as a motor, transformer, a clutch 20 mechanism and a barrier drive. Indeed, the only part of the operator that may be located outside the housing may be a remote control fob or unit.

In one embodiment, the operator of the third aspect of the invention includes the features of the operator according to the second aspect of the invention.

In order that the invention may be more readily understood and put into practice, 25 one or more preferred embodiments thereof will now be described, by way of example only, with reference to the accompanying drawings.

Brief Description of the Drawings FIGURE 1 is an exploded view of a barrier operator including a clutch mechanism according to a preferred embodiment of the present invention. 30 FIGURE 2 is a perspective view of the base mount of the clutch mechanism in FIGURE 1. FIGURE 3 is a perspective view of the control member of the clutch mechanism in FIGURE 1. 9 2012258284 22 Feb 2017 FIGURE 4 is a perspective view of the fixed member of the clutch mechanism in FIGURE 1. FIGURE 5 is a close up exploded view of the engagement member and the first and second retaining members of the clutch mechanism in FIGURE 1. 5 FIGURE 6A is a perspective cross-sectional view of a sub-assembly of the clutch mechanism in FIGURE 1 showing the components in the sub-assembly being arranged in the engaged position. FIGURE 6B is a side view of the sub-assembly in FIGURE 6A. FIGURE 7A is a perspective cross-sectional view of a sub-assembly of the 10 clutch mechanism in FIGURE 1 showing the components of the sub-assembly being arranged in the disengaged position. FIGURE 7B is a side view of the sub-assembly in FIGURE 7A. FIGURES 8 to 15 illustrate the step by step assembly of the barrier operator in FIGURE 1. 15 FIGURE 16 illustrates a perspective cross-sectional view of the assembled barrier operator in FIGURE 1. FIGURE 17 is a perspective view of a sub-assembly of a barrier operator according to a further embodiment of the present invention. FIGURE 18 illustrates various views of an assembled barrier operator according 20 to an embodiment of the present invention.

Detailed Description of Preferred Embodiment(s)

It will be appreciated that the drawings have been provided for the purpose of illustrating a preferred embodiment of the present invention. Therefore, it will be 25 understood that the present invention should not be limited to the features as shown in the drawings.

Figure 1 is an exploded view of a barrier operator 10 including a clutch mechanism 12. The barrier operator 10 has a drive shaft 14 which transfers rotational movement from a motor 16. The drive shaft 14 engages with a drive gear 18 such that 30 operation of the motor causes the drive gear 18 to rotate. The drive gear 18 is disposed adjacent an inner side of a back-plate 20 of the barrier operator 10. The motor 16 is mounted on an outer side of the back-plate 20. The barrier operator 10 also has a barrier drive 22 for engaging and driving a barrier, such as a roller door for a garage or the like (not shown) when rotational movement from the drive shaft 14 is transmitted to the 10 2012258284 22 Feb 2017 barrier drive 22. The barrier drive 22 has six openings 62 (only one of which is numbered in Figure 1) equally spaced in a generally circular layout in the barrier drive 22. The barrier drive 22 also has two fingers 64 for driving a barrier, such as a roller door for a garage. 5 The clutch mechanism 12 has a base mount 24, a control member 26, a fixed member 28, an engagement ring 30 that carries a plurality of engagement projections 32 (only one of which is numbered in Figure 1), a first retaining member 34, a second retaining member 36, a rotatable member 38, and a set of three helical springs 40.

As shown in Figures 1 and 2, the base mount 24 is mounted to the outer side of 10 the back-plate 20. The base mount 24 provides an axle 42 through an opening 21 in the back-plate 20. The axle 42 locates and defines a rotational axis for the control member 26, the engagement ring 30, the first retaining member 34, the second retaining member 36, the rotatable member 38 and the barrier drive 22. As shown in Figure 2, the base mount 24 defines a recessed portion 23. The base mount 24 also has feet 25 for 15 attachment to the outer side of the back-plate 20 (also see Figure 9). Feet 25 are provided with openings to allow the base mount 24 to be secured to the back-plate 20 by use of appropriate fasteners, such as screws or nuts or bolts. When the feet 25 of the base mount 24 are secured to the outer surface of the back-plate 20, the recessed portion 23 of the base mount 24 corresponds with the opening 21 of the back-plate 20 to define 20 a region of space which allows movement of the control member 26 towards and away from the fixed member 28. Detailed operation of the control member 26 and the fixed member 28 is described below.

As shown in Figures 1 and 3, the control member 26 has a generally ring shaped body 27 which is positioned around the axle 42. The ring shaped body of the control 25 member 26 has a serrated inner surface which defines a first set of recesses 44a and a second set of recesses 44b. The first set of recesses 44a are deeper and larger than the second set of recesses 44b (more clearly shown in Figure 3). The control member 26 has three arms 46. The function of the arms 46 will be explained hereunder.

As shown in Figures 1 and 4, the fixed member 28 also has a ring shaped body 30 29 which is positioned around the axle 42. The fixed member 28 has three legs 48 (only two are shown in Figure 1) disposed around the periphery of the ring shaped body of the fixed member 28 and the legs 48 are rigidly attached to attachment points 50 via fasteners such as nuts and bolts and/or screws (also see Figure 8). Suitably, the fasteners that secure the base mount 24 to the back-plate 20 also secure fixed member 28 to the 11 2012258284 22 Feb 2017 back-plate 20. The ring shaped body of the fixed member 28 has a serrated edge which defines a plurality of triangular shaped protrusions 52. As more clearly shown in Figure 4, each of the protrusions 52 is substantially identical in shape and size to each other.

As shown in Figures 1 and 5, the engagement ring 30 has a ring shaped body 31 5 which is also positioned around the axle 42. The engagement ring 30 has six engagement projections 32 equally spaced around the ring shaped body 31 of the engagement ring 30. The first retaining member 34 comprises two parts which can be separated and fastened together to appropriately fit around the arms 46 of the control member 26 (explained in further detail with reference to Figure 10). The engagement 10 ring 30 is fitted between the first retaining member 34 and the second retaining member 36. The second retaining member 36 is fastened over the first retaining member 34 via two clips 54 provided around the periphery of the second retaining member 36. The screw holes 55 of the second retaining member 36 (only one numbered in Figure 5) correspond with the screw holes 57 of the first retaining member 34 (only one 15 numbered in Figure 5). Fasteners such as screws, nuts, bolts and/or pins may be used through the screw holes 55 and 57 to secure the first retaining member 34 relative to the second retaining member 36.

As more clearly shown in Figure 5, the first retaining member 34 can be separated into two parts. The two parts of the first retaining member 36 can be clipped 20 together or fastened together by screws, pins or the like after they are positioned properly. To assemble the components shown in Figure 5, the engagement ring 30 is inserted into the first retaining member 36. (The positioning of the two-part first retaining member 34 is described in more detail below.) The second retaining member 36 has clips 54 which can be received by corresponding indents 56 around the periphery 25 of the first retaining member 34. Accordingly, the engagement ring 30 is sandwiched between the first retaining member 34 and the second retaining member 36 such that the engagement ring 30, the first retaining member 34 and the second retaining member 36 form a sub-assembly positioned around the axle 42. The sub-assembly is capable of moving together as a single entity. 30 Now referring back to Figure 1, the rotatable member 38 has a ring shaped body with a rim portion. The rim portion defines a ring gear 58 (also see Figure 16) having a plurality of teeth on the inner surface of the ring gear 58. The rotatable member 38 also has six apertures 60 equally spaced in a circular arrangement on the ring shaped body of 12 2012258284 22 Feb 2017 the rotatable member 38. The engagement projections 32 of the engagement member 30 can extend through the apertures 60.

The springs 40 are fixed to the inner surface of the back-plate 20 and acts between the back-plate 20 and the first retaining member 34 (also see Figure 12). 5 As illustrated in Figures 6A and 6B, in the engaged position, the control member 26 is rotated in a first direction until it reaches an engaged position where the first set of recesses 44a receive the projections 52. The relative positions of the control member 26 and the fixed member 28 define a first separation distance ‘df between the fixed member 28 and the arms 46 of the control member 26 (see Figure 6B). As shown in 10 Figures 6A and 6B, each arm 46 has a lip 66 for engagement with a lower internal flange 68 of the first retaining member 34. An outer peripheral portion 70 of the engagement ring 30 is rigidly held between a first rim 72 of the first retaining member 34 and a second rim 74 of the second retaining member 36. The engagement projections 32 are inserted through the apertures 60 of the rotatable member 38 and the openings 62 15 of the barrier drive 22.

When the motor is turned on, the drive gear 18 rotates and drives the rotatably member 38 via engagement with the ring gear 58. As the engagement projections 32 are inserted into the apertures 60 of the rotatable member 38 and the openings 62 of the barrier drive 22, the rotation of the rotatable member 38 is transferred through the 20 engagement projections 32 to the barrier drive 22. The barrier drive 22 then drives a barrier through fingers 64.

When the motor 16 is to be disengaged with the barrier drive 22, the control member 26 is moved into the disengaged position by rotating the control member 26 in a second direction opposite to the first direction. In other embodiments, it will be 25 understood that the control member may move in any direction between the engaged position and the disengaged position.

As illustrated in Figures 7A and 7B, in the disengaged position, the protrusions 52 of the fixed member 28 are received in the second set of recesses 44b of the control member 28. As the second set of recesses 44b are smaller and shallower than the first 30 set of recesses 44a and as the separation distance between the fixed member 28 and the back-plate 20 is fixed, the control member 26 moves away from the fixed member 28. The region of space defined by the recessed portion 23 of the base mount 24 and the opening 21 of the back-plate 20 provides room for the control member 26 to move away from the fixed member 28. In the disengaged position, the ring shaped body 27 of the 13 2012258284 22 Feb 2017 control member 28 is inserted further into the recessed portion 23 of the base mount 24 (explained in further detail with reference to Figure 16).

In the disengaged position, the relative positions of the control member 26 and the fixed member 28 define a second separation distance ‘d25 between the fixed member 5 28 and the arms 46 of the control member 26 (see Figure 7B). The second separation distance is greater than the first separation distance ‘di. As the separation distance between the fixed member 28 and the back-plate 20 is fixed and the distance between the engagement ring 30 and the lower internal flange 68 is also fixed, an increase in the separation distance from ‘di’ to ‘d2’ causes the lips 66 of the arms 46 pull the 10 engagement ring 30 closer to the back-plate 20 by acting on the lower internal flange 68. The springs 40 are compressed by the movement of the first retaining member 34 closer to the back-plate 20. The movement of the engagement ring 30 closer to the back-plate 20 withdraws the engagement projections 32 from the openings 62 of the barrier drive. However, the engagement projections 32 still remain in the apertures 60 of the 15 rotatable member 38. In the disengaged position, when the motor 16 is turned on, the rotation of the drive gear 18 drives the rotatable member 38 via the ring gear 58. However, the rotation of the rotatable member 38 is not transferred to the barrier drive 22. Accordingly, the barrier drive 22 can be moved manually with a barrier, for example, in the event of a power outage. 20 When it is desirable to re-engage the motor 18 with the barrier drive 22, the control member 26 is rotated in the first direction so that the protrusions 52 are received in the first set of recesses 44a. The control member 26 moves outwardly with respect to the recessed portion 23 of the base mount 24 and closer to the fixed member 28, thereby reducing the separation distance between the control member 26 and the fixed member 25 28 back to ‘di’. However, if the openings 62 in the barrier drive 22 are not aligned with the engagement protrusions 32 of the engagement ring 30, the springs 40 remain compressed. As the first retaining member 34, the engagement ring 30 and the second retaining member 36 cannot move away from the back-plate 20 as the control member 26 is moved to the disengaged position, the lips 66 of the control member 26 no longer 30 engage with the lower internal flange 68 of the first retaining member 34. When the motor 16 is turned on, the drive gear 18 drives the rotatable member 38, which turns the engagement projections 32. When the engagement projections 32 become aligned with the openings 62 of the barrier drive 22, the engagement projections 32 are pushed into 14 2012258284 22 Feb 2017 the openings 62 immediately by action of the springs 40, thereby enabling the motor 18 to re-engage and drive the barrier drive 22.

Figures 8 to 15 show the various steps involved in assembling the barrier operator 10. Figures 8 and 9 show the mounting of the base mount 24 on the outer 5 surface of the back-plate 20 and providing the axle 42 through an opening 21 in the back-plate 20. Figure 8 shows that the control member 26 is fitted around the axle 46 immediately adjacent the base mount 24. The ring shaped body 27 of the control member 26 is sized to fit within the recessed portion 23 of the base mount 24. The fixed member 28 is fitted over the control member 26 and the legs 48 of the fixed member 28 10 are fixed to the back plate 20, together with the feet 25 of the base mount 24 via screws 76.

It is shown in Figure 10 that the first retaining member 34 is fitted over and around the control member 26. The first retaining member 34 can be separated into two parts (see Figures 1 and 5) so the lower internal flange 68 of the first retaining member 15 34 can be properly fitted under the arms 46 of the control member 26.

As shown in Figure 11, the engagement ring 30 is placed over the first retaining member 34.

As shown in Figure 12, the second retaining member 36 is fitted over the engagement ring 30 and secured in place using screws 78. It can also be seen in Figure 20 12 that the springs 40 (only one shown) are fitted between the back-plate 20 and the bottom of the first retaining member 34.

Figure 13 shows an operating rod 80 adjacent the outer surface of the back-plate 20. The operating rod 20 is connected to the control member 26 via a substantially ‘L’ or ‘V’ shaped linking member 82 such that when the operating rod is pulled and pushed, 25 the control member 26 can be rotated in the first and second directions.

Figure 14 shows that the rotatable member 38 is placed over the second retaining member 36 in the next step of the assembly process. The engagement projections 32 extend through the apertures 60 of the rotatable member 38.

Figure 15 shows that the barrier drive 22 is then fitted over the rotatable member 30 38.

Finally, Figure 16 shows a perspective cross-sectional view of the assembled barrier operator 10. As illustrated in Figure 16, in the engaged position, the engagement projections 32 are inserted into the openings 62 of the barrier drive 22 so that when drive gear 18 (hidden) drives the ring gear 58 of the rotatable member 38, the rotation of 15 2012258284 22 Feb 2017 the rotatable member 38 is transferred to the barrier drive 22 through the engagement projections 32.

When the control member 26 is moved into the disengaged position, the ring shaped body 27 of the control member 26 moves deeper into the recessed portion 23. In 5 this disengaged position, the lips 66 of arms 46 pull the first retaining member 34 closer to the back-plate 20, which also moves the engagement member 30 closer to the back-plate 20. Consequently, the engagement projections 32 are withdrawn from the openings 62 of the barrier drive 22. Therefore, in the disengaged position, the rotatable member 38 and the barrier drive 22 can rotate independently from one another to allow 10 manual operation of the barrier drive 22.

The configuration of the barrier operator 10 according to a preferred embodiment of the present invention allows the barrier drive 22 to become engaged and disengaged with the motor 16 with minimal lateral movement by the control member 26. Accordingly, the barrier operator 10 is very compact and can be fitted entirely 15 within the interior of a drum of the barrier.

As shown in the attached figures, the operator may have a radial extent that is no bigger than the radial extent of the drum of the barrier. This allows the operator to be mounted in-drum, if desired. The major components of the operator, including the motor, transformer, clutch and drive, as well as the control board or control circuitry, 20 are all located within the housing of the operator. This enables in-drum mounting without having any parts of the operator requiring separate mounting. Indeed, the only part of the operator that needs to be positioned out of the drum is the remote control fob, which is typically kept on a person or in a vehicle.

It will also be understood that the operator may be mounted outside the drum, if 25 desired.

Figure 17 illustrates a perspective view of a sub-assembly of a barrier operator 100 according to a further embodiment of the present invention. The barrier operator 100 functions in the same manner as barrier operator 10 as described previously with reference to Figures 1 to 16. 30 In addition to the components described with respect to barrier operator 10, barrier operator 100 includes a further balancing gear 200 (i.e. idler gear) located on an opposite side of the axle 42 to the drive gear 18 for balancing the rotatable member 38 (not shown) such that the rotatable member 38 rotates in a smooth and continuous motion. 2012258284 22 Feb 2017 16

In an alternative embodiment, the balancing gear 200 may not be located directly opposite the drive gear 18 as shown in Figure 17. Instead, the balancing gear may be spaced from the drive gear 18 at any suitable location around the periphery of the rotatable member 38. 5 The attached drawings show an embodiment of the present invention that falls within the scope of the second aspect of the present invention and within the scope of the third aspect of the present invention. FIGURE 18 illustrates various views of an assembled barrier operator according to an embodiment of the present invention. 10 The foregoing embodiments are illustrative only of the principles of the invention, and various modifications and changes will readily occur to those skilled in the art. The invention is capable of being practiced and carried out in various ways and in other embodiments. It is also to be understood that the terminology employed herein is for the purpose of description and should not be regarded as limiting. 15 The term “comprise” and variants of that term such as “comprises” or “comprising” are used herein to denote the inclusion of a stated integer or integers but not to exclude any other integer or any other integers, unless in the context or usage an exclusive interpretation of the term is required.

Reference to prior art disclosures in this specification is not an admission that 20 the disclosures constitute common general knowledge in Australia.

Claims (14)

1. The claims defining the invention are as follows:

   1. A clutch mechanism for a barrier operator, the barrier operator comprising a motor, a barrier drive for engaging with a barrier such that rotation of the barrier drive moves the barrier, the clutch mechanism being configured to transfer drive from the motor to the barrier drive, the clutch mechanism comprising a rotatable member driven for rotation by the motor, at least one engagement member movable between an engaged position and a disengaged position, the at least one engagement member including one or more projections configured to be inserted into the barrier drive for engagement therewith, the barrier drive defining or having one or more corresponding openings to receive the one or more projections of the at least one engagement member when the at least one engagement member is in the engaged position, the rotatable member defining or having one or more corresponding openings to receive the one or more projections of the at least one engagement member such that rotation of the rotatable member causes rotation of the at least one engagement member at all times, wherein in the engaged position the one or more projections extend into the corresponding one or more openings of the barrier drive and in the disengaged position the one or more projections are retracted from the openings of the barrier drive and out of engagement with the barrier drive, wherein the rotatable member defines one or more corresponding openings to receive the one or more projections of the at least one engagement member such that rotation of the rotatable member causes rotation of the at least one engagement member at all times, and wherein when the at least one engagement member is in the disengaged position, operation of the motor causes rotation of the rotatable member without causing rotation of the barrier drive, whereby manual operation of the barrier is permitted when the at least one engagement member is in the disengaged position.
2. 2. The clutch mechanism according to claim 1, wherein the at least one engagement member moves linearly between the engaged position and the disengaged position.
3. 3. The clutch mechanism according to claim 1 or claim 2, further including a control member, wherein rotation of the control member causes the at least one engagement member to move between the engaged position and the disengaged position.
4. 4. The clutch mechanism as claimed in claim 3, further including a fixed member mounted to a back plate such that a distance between the fixed member and the back plate is fixed, the control member cooperating with the fixed member such that rotation of the control member relative to the fixed member moves the control member laterally to thereby move the at least one engagement member between the engaged position and the disengaged position.
5. 5. The clutch mechanism as claimed in claim 4, wherein the fixed member has engagement teeth for engagement with the control member, and the control member has a first set of recesses and a second set of recesses smaller than the first set of recesses for receiving the engagement teeth, and wherein rotation of the control member causes the engagement teeth to move between the first set of recesses and the second set of recesses to thereby cause lateral movement of the control member with respect to the fixed member.
6. 6. The clutch mechanism according to any one of the preceding claims, further including biasing means for biasing the at least one engagement member towards the engaged position.
7. 7. The clutch mechanism according to any one of the preceding claims, wherein the rotatable member includes a ring gear portion for engagement with a drive gear of the motor.
8. 8. The clutch mechanism as claimed in claim 7, further including a balancing gear spaced from the drive gear for balancing the rotatable member.
9. 9. An operator for a barrier comprising a motor, a barrier drive for engaging with the barrier such that rotation of the barrier drive moves the barrier, a drive train for transferring drive from the motor to the barrier drive, the drive train comprising a clutch mechanism according to any one of the preceding claims.
10. 10. The operator as claimed in claim 9, the operator comprising one or more fingers for engagement with the barrier.
11. 11. The operator as claimed in claim 9 or claim 10, wherein the barrier has a drum and the operator has a radial extent that is less than a radial extent of the drum.
12. 12. The operator as claimed in claim 11, wherein the barrier has a drum and the operator can be fitted entirely within the drum.
13. 13. The operator as claimed in claim 11 or 12, wherein an outer housing of the operator has a radial extent that is less than a radial extent of the drum of the barrier.
14. 14. The operator as claimed in claim 13, wherein the outer housing contains all components of the operator.