[0001] This invention relates to remote control door mechanisms particularly garage doors
of the so-called up-and-over type.
[0002] There are basically two types of up-and-over door arrangements, namely the retractable
type in which horizontal tracks extending backwardly from the door frame for supporting
the upper edge of the door panel when it is opened and the canopy-type in which the
door panel is suspended on pivoted links and a spring loaded lifting arrangement is
provided for counterbalancing the door panel. The latter type is the less expensive
and the easier to install as all the parts of the door mechanism are mounted in the
plane of the door opening. However, it is relatively difficult to provide remotely
controllable power operating means for canopy-type doors as the motion of the door
during opening is complex.
[0003] Various remotely controllable power operating arrangements have, nonetheless, been
proposed in the past, but these have tended to suffer from considerable complication,
making installation a difficult task and requiring a precision beyond the competence
of many building construction workers.
[0004] It is one object of the present invention, therefore, to provide a door mechanism
which is very simple to install.
[0005] In accordance with one aspect of the invention there is provided, as an article of
manufacture, a door mechanism comprising the combination of:
(a) a rigid frame for mounting in a door opening;
(b) a door panel;
(c) door panel suspension means suspending the door in the frame for up-and-over opening
movement;
(d) door panel counterbalancing means acting between the frame and the door panel;
and
(e) power operable door operating means mounted on said frame and operatively coupled
to the door.
[0006] With such an arrangement, the door frame, the door panel, the suspension means, the
counterbalancing means, and the power operable door operating means are supplied pre-assembled
and ready to attach in a door opening. The amount of skill required by the installer
is much reduced as compared with the prior art arrangements.
[0007] Preferably the frame is of inverted U-shaped configuration and the power-operable
door operating means is mounted on the upper member of the frame.
[0008] Preferably also, the counterbalancing means includes a rotary shaft, and the door
operating means comprises a motor which is operatively coupled to the door via the
rotary shaft. The motor is preferably coupled to the shaft via a clutch. The door
mechanism preferably also includes a bolt on the door and the motor may also be arranged
to drive a capture device for drivingly engaging the bolt and displacing the latter
between closed and partially open positions.
[0009] The invention also has as an object to provide a convenient form of door operating
mechanism which is both inexpensive to construct and reliable in operation.
[0010] In accordance with this aspect of the invention, there is provided a power operable
door operating mechanism for a canopy-type up-and-over door which includes a motor
driven door bolt capture device for drivingly engaging a bolt on the door and displacing
the latter between closed and partially opened positions, means for detecting positioning
of the door in said partially open position and motor driven means for applying rotary
movement to a shaft forming part of door counterbalancing means for urging the door
from its partially open position towards a fully open position.
[0011] Preferably, the same motor is employed for driving said bolt capture device and said
means for applying rotary movement to said shaft. Conveniently said means for applying
torque to said shaft includes a clutch arrangement under the control of said door
position detecting means to be disengaged when the door is between said partially
open position and said closed position.
[0012] In one convenient arrangement, said bolt capture means comprises a drive chain with
which the bolt is engageable which chain transmits torque to the clutch input side.
[0013] An example of the invention is shown in the accompanying drawings in which:
Figure 1 is a perspective view of a door arrangement in accordance with the invention;
Figure 1A is a fragmentary section taken on line A-A in Figure 1 and showing a guide
arrangement for the door;
Figure 1B is a fragmentary section of a modification of the arrangement shown in Figure
1A;
Figure 2 is a plan view of part of a motorised operating gear for the door;
Figure 3 is a view of a retractable door bolt which coacts with the operating gear;
and
Figure 4 is a fragmentary view showing the door in a partially open position.
[0014] As shown in Figure 1 the door arrangement comprises a rigid inverted U-shaped outer
door frame 10 on which a door panel 11 is suspended by door suspension means. The
suspension means is of a type which is already known in principle, comprising a shaft
12 extending along the top of the door opening, counterbalancing spring means 13 for
applying torque to the shaft 12, a pair of links 14 each pivotally connected at one
end to a bracket 15 on the frame and at the other end to the door panel, and means,
in the present case a pair of drive chains 16 on sprockets 17 on the shaft, connecting
the shaft points on the door panel below the lower ends of the links 14 when the door
is closed. Suspension means of this type usually includes a single long counterbalancing
spring, but in the present construction two such springs are employed respectively
acting on opposite end portions of the shaft. The points to which the chains 16 are
connected are shown in more detail in Figure 1A, from which it will be seen that there
is a guide pin 18 fixed to the door at each such point and projecting into a guide
channel 19 attached to the adjacent vertical leg of the frame 10. A roller 20 on the
pin fits in the channel to provide a smooth low friction guide action. Each chain
16 has its two ends connected to a link 21 on the pin 18. In an alternative arrangement
the chain may be contained within the door frame 10 and the guide channel 19. An example
of this is shown in Figure 1B, in which the frame 10 has side members made up of a
closed channel, with a box section secured inside it. One run of the chain is in the
box section.
[0015] The door suspension itself operates in a substantially conventional manner, that
is to say the springs 13 are pre-tensioned to provide drive torque to the shaft 12.
This drive torque causes the chains 16 to apply an upward force on the pins 18, but
as these pins 18 lie directly below the links 14 which extend substantially vertically
when the door is closed, there is no turning moment on the door. It is possible, however,
in the absence of any locks, bolts or latches holding the door shut, to push the upper
part of the door inwardly which results in a turning moment being applied to the door
by the springs 13 via the chains 16. Initially this moment is small, but as the links
14 swing inwardly and the pins 18 travel up the guides 19, the moment increases, although
the torque produced by the spring increases.
[0016] The linkage geometry and the spring pre-tension are such that, at the closed end
of the door travel the moment of the door's weight exceeds the moment of the counterbalancing
torque so that the door is urged shut. At the opposite end of the door travel the
door is urged open by the combined effects of gravity and the counterbalancing springs.
[0017] To enable the door arrangement described above to be motor driven a drive gear is
provided which as shown in Figure 2, when actuated, initially tilts the door to a
partially open position and then drives the door fully open by turning the shaft 12.
The drive gear comprises a drive chassis 30 attached to the upper rail of the door
frame at the centre thereof. A drive motor 31 mounted on the chassis 30, provides
drive action to a sprocket spindle 32 via a worm and pinion drive 33. A sprocket 34
on the spindle 32 is engaged with an endless chain 35 which also extends around a
similar sprocket forming the input member of a friction clutch 37 the output member
of which is fast with the shaft 12. The clutch 37 is operated by a spring 38 on the
shaft 12 which urges the clutch parts into driving engagement. A lever 39 pivotally
mounted at one end on the chassis is provided for disengaging the clutch by relieving
the force applied by spring 38 when required.
[0018] The chain 35 forms part of a door bolt capture arrangement. A bolt 41 mounted on
the upper part of the door has a notched end to enable it to engage lugs provided
on opposite sides of the chain. Thus when the chain is driven whilst the bolt is engaged,
the upper part of the door is moved towards or away from the frame depending on the
direction of drive.
[0019] The bolt 41 also co-acts with the lever 39 to form a door position detecting means.
When the bolt 41 is engaged with the chain 35, it also engages the lever, turning
it against the spring loading to disengage the clutch. Thus, when the door is closed,
the bolt causes the clutch 37 to disengage. If the motor is driven in door opening
position, the bolt is carried away from the frame, opening the door, until the bolt
eventually becomes disengaged from both the chain 35 and the lever 39. The clutch
37 is now engaged so that continued rotation of the motor shaft is transmitted via
the chain 35 and the clutch 37 to the spindle 12, thereby raising the pins 18 and
continuing opening movement of the door.
[0020] From the open position of the door, rotation of the motor shaft in the door closing
position will initially cause progressive lowering of pins 18 and consequent door
closing movement, until the bolt 41 becomes engaged with chain 35 and lever 39. This
causes the clutch to be disengaged and final closing movement is effected by capture
of the bolt by chain 35.
[0021] It will be appreciated that capture of the bolt 41 by the chain 35 effectively locks
the door closed, as the chain cannot drive the motor shaft through the worm and pinion
drive. Further latches may be provided at the sides of the door if required.
[0022] However, to allow manual door opening, the bolt 41 can be manually withdrawn downwardly
out of engagement with the chain 35 and lever 39. This allows some inward movement
of the upper edge of the door to be initiated, but as the clutch becomes engaged when
the bolt is withdrawn such movement is limited. As shown in Figure 2, however, a separate
mechanism is provided for displacing lever 39 when required to release the clutch.
This mechanism employs a cam 42 in a hole in the lever 39. The cam can be turned by
a knob, handle or key on the underside of the chassis.
[0023] In an alternative arrangement (not shown), an L-shaped manual release lever is pivotally
mounted by a vertical pivot pin in a pressed steel chassis having an inverted channel
section in which the chain 35 and sprockets, the clutch 36 and a clutch lever (having
a similar function to lever 39) are mounted. A clutch-adjacent end of the clutch lever
is pivotally mounted on the chassis via a vertical pivot pin. One of the arms of the
manual release lever projects through a slot in an end plate fitted to the inner end
of the chassis so that such arm is exposed for manual operation. The other arm of
the manual release lever is engageable with the end of the clutch lever remote from
the clutch so that manual pivoting of the lever can be effected to cause the clutch
lever to release the motor drive transmission. It is possible to attach a release
cable to the manual release lever to select manual operation from alongside the door
frame (which may for example be of benefit to an elderly or infirm door operator).
[0024] Although not shown in the drawings, detectors are provided for sensing when the door
is fully open and fully closed and for stopping the motor. These detectors may form
part of a remotely controllable motor control circuit (not shown). The detectors may
be provided as limit switches (optical, electrical or magnetic). One such switch or
other detector may be in the chassis 30 and detects the arrival of the bolt 41 at
the door closed position. The other may be arranged to co-act with the pin 18 to detect
the door open condition. Alternatively, the detector arranged to detect the door open
condition may be a motor current sensor which detects when the motor current rises
as a result of the motor stalling when one of the rollers 20 engages against a rubber
stop.
[0025] As mentioned above, the door is supplied pre-assembled with the frame so that it
can be mounted very easily behind a door opening. All necessary adjustments to the
mechanism can thus be made during manufacture of the door/frame assembly so as to
ensure that there is no difficulty in setting up the operating gear on installation.
[0026] The use of a chain drive as part of the bolt capture means is particularly advantageous
as it allows the same motor to drive the bolt and the shaft. It is to be understood,
however, that the invention may also be realised utilising quite different bolt capture
and shaft-rotating arrangements. These could, for example, be driven by two independent
motors if required, and the invention also comprehends the use of door position detecting
switches to switch drive between one motor and the other at the point where the limit
of bolt capture drive is reached.
1. A door mechanism as an article of manufacture comprising the combination of:
(a) a rigid frame for mounting in a door opening;
(b) a door panel;
(c) door panel suspension means suspending the door in the frame for up-and-over opening
movement;
(d) door panel counterbalancing means acting between the frame and the door panel;
and
(e) power operable door operating means mounted on said frame and operatively coupled
to the door.
2. A door mechanism as claimed in claim 1, wherein the frame is of inverted U-shaped
configuration and the power-operable door operating means is mounted on an upper member
of the frame.
3. A door mechanism as claimed in claim 1 or 2, wherein the counterbalancing means includes
a rotary shaft, and the door operating means comprises a motor which is operatively
coupled to the door via the rotary shaft.
4. A door mechanism as claimed in claim 3, wherein the motor is coupled to the shaft
via a clutch.
5. A door mechanism as claimed in any preceding claim, further including a bolt on the
door, and wherein the motor is arranged to drive a capture device for drivingly engaging
the bolt and displacing the latter between closed and partially open positions.
6. A power operable door operating mechanism for a canopy-type up-and-over door which
includes a motor driven door bolt capture device for drivingly engaging a bolt on
the door and displacing the latter between closed and partially opened positions,
means for detecting positioning of the door in said partially open position, and motor
driven means for applying rotary movement to a shaft forming part of door counterbalancing
means for urging the door from its partially open position towards a fully open position.
7. A mechanism as claimed in claim 6, wherein the same motor is employed for driving
said bolt capture device and said means for applying rotary movement to said shaft.
8. A mechanism as claimed in claim 6 or 7, wherein said means for applying rotary movement
to said shaft includes a clutch arrangement under the control of said door position
detecting means to be disengaged when the door is between said partially open position
and said closed position.
9. A mechanism as claimed in claim 8, wherein said bolt capture device comprises a drive
chain with which the bolt is engageable, which chain transmits torque to an input
side of the clutch arrangement.
10. A mechanism as claimed in claim 1 or 6, substantially as hereinbefore described with
reference to the accompanying drawings.