NZ603515B2 - A Clutch Mechanism - Google Patents

Abstract

clutch mechanism for a barrier operator, the barrier operator comprising a motor (16), a barrier drive (22) for engaging with a barrier such that rotation of the barrier drive moves the barrier, the clutch mechanism (12) being configured to transfer drive from the motor to the barrier drive, the clutch mechanism comprising a rotatable member (38) driven for rotation by the motor, at least one engagement member (30) 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 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, 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. The clutch mechanism further includes a fixed member (48), mounted to a backing plate (20), and a control member (26). The control member is rotated with respect to the fixed member to move the engagement member between the engaged and disengaged position. lutch mechanism comprising a rotatable member (38) driven for rotation by the motor, at least one engagement member (30) 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 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, 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. The clutch mechanism further includes a fixed member (48), mounted to a backing plate (20), and a control member (26). The control member is rotated with respect to the fixed member to move the engagement member between the engaged and disengaged position.

Description

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 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.

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.

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.

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.

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, a drive gear rotatably driven by operation of the 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, wherein in the engaged position the at least one engagement member is in engagement with the barrier drive, and in the disengaged position the at least one engagement member is out of engagement with the barrier drive, the at least one engagement member including one or more projections, wherein when the at least one engagement member is in the engaged position and engaged with the rotatable member, the one or more projections extend into the openings defined in the barrier drive such that 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, the one or more projections are retracted from the openings in the barrier drive such that 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. The clutch mechanism 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 and 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 axially to thereby move the at least one engagement member between the engaged position and 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 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, 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 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 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 - 2a - 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.

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 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 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 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.

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 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 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 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.

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.

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.

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 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 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 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.

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 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 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 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 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 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 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.

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 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 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 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.

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 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 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 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.

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 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 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 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 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 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 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.

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 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 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.

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 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, 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.

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.

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.

Claims (13)

The claims defining the invention are as follows:

1. A clutch mechanism for a barrier operator, the barrier operator comprising a motor, a drive gear rotatably driven by operation of the motor, a barrier drive for engaging with a barrier such that rotation of the barrier drive moves the barrier, the barrier drive defining one or more openings, 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 drive gear, 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 drive, and in the disengaged position the at least one engagement member is out of engagement with the barrier drive, the at least one engagement member including one or more projections, wherein when the at least one engagement member is in the engaged position and engaged with the rotatable member, the one or more projections extend into the openings defined in the barrier drive such that 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, the one or more projections are retracted from the openings in the barrier drive such that 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, the clutch mechanism 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 and 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 axially to thereby move the at least one engagement member between the engaged position and the disengaged position.

2. The clutch mechanism as claimed in claim 1, 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.

3. The clutch mechanism according to claim 1 or claim 2, wherein the at least one engagement member moves linearly between the engaged position and the disengaged position.

4. The clutch mechanism as claimed in any one of the preceding claims, 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.

5. 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.

6. 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.

7. The clutch mechanism as claimed in claim 8, further including a balancing gear spaced from the drive gear for balancing the rotatable member.

8. 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.

9. The operator as claimed in claim 8, the operator comprising one or more fingers for engagement with the barrier.

10. The operator as claimed in claim 8, wherein the barrier has a drum and the operator has a radial extent that is less than a radial extent of the drum.

11. The operator as claimed in claim 8, wherein the barrier has a drum and the operator can be fitted entirely within the drum.

12. The operator as claimed in claim 10 or 11, wherein an outer housing of the operator has a radial extent that is less than a radial extent of the drum of the barrier.

13. The operator as claimed in claim 12, wherein the outer housing contains all components of the operator.