Information
-
Patent Grant
-
6792998
-
Patent Number
6,792,998
-
Date Filed
Thursday, March 21, 200222 years ago
-
Date Issued
Tuesday, September 21, 200420 years ago
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Inventors
-
-
Examiners
Agents
-
CPC
-
US Classifications
Field of Search
US
- 160 201
- 160 265
- 160 207
- 160 2731
- 160 280
- 160 281
- 016 DIG 1
- 016 87 R
- 016 91
- 016 106
- 016 97
- 016 229
-
International Classifications
-
Abstract
The present invention is a device which is designed to allow a door to give way when impacted by an outside force such as a forklift, reducing damage. The present invention requires less force to be activated, which allows its use on wider doors than were previously possible. The present invention is also able to reset itself, depending upon how much distance was traveled during the impact. The present invention requires less maintenance than other devices currently in use.
Description
I. FIELD OF THE INVENTION
This invention relates to a guide system mounted on an overhead door, specifically an overhead door which is guided along a predetermined path by a pair of tracks, and is able to be disengaged from one or both tracks when acted upon by an outside force. Once the outside force is removed, the door is able to automatically reset itself into the tracks. This ability to be disengaged will greatly reduce the possibility of damage to the overhead door other components of the installation.
II. BACKGROUND OF THE INVENTION
During the course of daily activity around a loading dock or other industrial location, an overhead door may be impacted by a truck, forklift, or other forceful means. If the door is not able to move with this impact, damage to the door, tracks, or other objects will result. Various means have been used to allow a door to move out of its tracks to avoid such damage.
For example, U.S. Pat. No. 5,535,805 discloses an overhead door system in which a spring loaded pin retracts into a housing when the door is impacted. The pin is forced into its housing by means of a track whose cross section employs a slanted ramp. There are several disadvantages in this system. One disadvantage is that it is necessary to use a track with a ramped cross section. This limits the choice of door tracks, and any deformity in the ramped cross section will hinder proper operation. Another disadvantage is that the pin and its associated components must be kept lubricated and free of corrosion for it to work properly. Yet another disadvantage is that this system is limited to use on doors which are no wider than 16 feet. If a wider door is impacted, it is likely that the door will buckle before there is adequate force applied at the ends of the door to move the spring loaded pin up the ramp, unless the door is heavily reinforced.
III. SUMMARY OF THE INVENTION
A. Objects of the Invention
One object of the present invention is to provide a means to protect doors and their associated components from extensive damage resulting from an impact by an outside force.
Another object of the present invention is to provide a means for the protection device to automatically reset once the outside force is removed.
Another object of the present invention is to provide a means to protect very wide doors.
Another object of the present invention is to provide means to install this system on existing doors with a variety of track styles.
B. Summary
The present invention is a device which is designed to allow a door to give way when impacted by an outside force such as a forklift, reducing damage. The present invention requires less force to be activated, which allows its use on wider doors than were previously possible. The present invention is also able to reset itself, depending upon how much distance was traveled during the impact. The present invention requires less maintenance than other devices currently in use.
IV. THE DRAWINGS
FIG. 1
is a perspective view of a typical installation.
FIG. 2A
is a perspective view of a typical installation after being impacted by an outside force.
FIG. 2B
is a perspective view of a typical installation after an outside force has been removed.
FIG. 3A
is a top view of the present invention in normal use.
FIG. 3B
is a top view of the present invention after impact by an outside force.
FIG. 3C
is a top view of the present invention after the outside force has been removed and it has automatically reset.
FIG. 3D
is a top view of the present invention after the outside force has been removed, but has moved too far to automatically reset.
FIG. 3E
is a top view of the present invention being manually reset.
FIG. 4A
is a view of the guide system showing its internal components.
FIG. 4B
is an end view of the guide system.
FIG. 5A
is a side view of the guide system in its normal (closed) position.
FIG. 5B
is a side view of the guide system in its activated (open) position.
FIG. 6A
is an exploded view of some internal components of the guide system mounted to shaft
100
.
FIG. 6B
is an exploded view of some internal components of the guide system mounted to shaft
300
.
V. DESCRIPTION OF PREFERRED EMBODIMENTS
In accordance with the present invention, guide system
15
is shown in a typical installation
10
in FIG.
1
. Each guide system
15
is mounted to the ends of door segments
20
,
21
,
22
(only one end is shown for clarity). Guide systems
15
ride in track
30
when the door moves up or down during normal operation.
FIG. 2A
shows installation
10
after it has been impacted by an outside force (such as a forklift). The door segment
22
to which guide system
45
is mounted has not been moved far enough to activate guide system
45
. The door segment
21
to which guide system
47
is mounted has been pushed out far enough that guide system
45
has been opened in arcuate movement
101
, but still riding in track
30
. The door segment
20
to which guide system
48
is mounted has been pushed out far enough that guide system
48
has once again closed, but is no longer riding in track
30
.
FIG. 2B
shows installation
10
after the outside force has been removed. The door segment
22
to which guide system
45
is mounted is still in track
30
. The door segment
21
to which guide system
47
is mounted has automatically reset itself so that guide system
45
is closed and again riding in track
30
. The door segment
20
to which guide system
48
is mounted was pushed out so far that guide system
48
closed, and now pin
110
is bearing against the outside of track
30
. It will need to be manually reset as is described hereinafter.
FIGS. 3A through 3E
show top views of the sequence described above.
FIG. 3A
shows guide system
15
mounted to door segment
20
. Pin
110
is in its normal position inside track
30
.
FIG. 3B
shows the condition which exists after door segment
20
was impacted by an outside force (the outside force is still in place), causing guide system to open in an arcuate movement
101
.
In this instance, door segment
20
was not moved so far out as to force pin
110
out of track
30
. Guide system
15
is open, but pin
110
is still inside track
30
. Tension spring
80
is stretched, exerting force on the segments of guide system
15
to help it remain in position.
FIG. 3C
shows the condition which exists after the outside force has been removed. Due to the force exerted by tension spring
80
, guide system
15
is once again closed and pin
110
is in its normal position inside track
30
.
FIG. 3D
shows the condition which exists after the outside force has been removed. In this instance, door segment
20
was moved far enough out to force pin
110
out of track
30
. Due to the force exerted by tension spring
80
, guide system
15
is once again closed, but pin
110
is now bearing on the outside of track
30
.
FIG. 3E
shows guide system
15
being manually reset. Handle
190
is pulled in direction
200
, which retracts shaft
100
and pin
110
away from track
30
, allowing door segment
20
to be once again moved into its proper position. When handle
190
is released, shaft
100
and pin
110
return to their original positions, as shown in FIG.
3
A.
FIGS. 4A through 5B
show the guide system and its internal components. Guide system
15
comprises a fixed housing
50
and a moveable housing
60
. Fixed housing
50
is mounted to door segment
20
,
21
,
22
by means of mounting lugs
96
and holes
95
. Hinge
70
allows moveable housing
60
to swing open and closed in an arcuate movement (FIG.
5
B). Moveable housing
60
is held closed to fixed housing
50
by means of tension springs
80
. One end of each tension spring
80
is attached to fixed housing
50
; the other end of tension spring
80
is attached to moveable housing
60
. This provides a very strong means to keep the two housings closed with respect to one another, keeping door segment
20
in proper alignment with track
30
during normal operation.
The action of tension springs
80
which keep the two housings closed with respect to one another facilitate the automatic reset of guide system
15
as previously described.
Pin
110
rides in track
30
, and may be made of nylon, teflon, or other material that provides preferably inherent lubrication for ease of operation and long life. Pin
110
is mounted to shaft
100
. Shaft
100
protrudes through the end of moveable housing
60
, and is free to slide back and forth, guided by guide pin assembly
120
which rides in slot
55
. The normal position of shaft
100
is maintained by compression spring
90
, which bears against bushing
140
and guide pin assembly
120
. Bushings
140
,
130
provide means for shaft
100
to move back and forth while reducing wear. Washer
150
provides a space between moveable housing
60
and lug
170
. The entire assembly is retained by retaining rings
160
,
180
. Handle
190
provides means for a user to retract shaft
100
.
Guide pin assembly
120
as shown in
FIGS. 6A and 6B
comprises body
121
, beveled end
122
, head
123
, and ball
125
. Guide pin assembly
120
is permanently mounted to shaft
100
(
FIG. 6A
) or
300
(
FIG. 6B
) via hole
115
by means of welding, bonding, or staking. Guide pin assembly
120
provides means to keep moveable housing
60
and fixed housing
50
together. When in the closed position as shown in
FIG. 5A
, ball
125
in the end of guide pin assembly
120
is outside of fixed housing
50
. When moveable housing
60
starts to open, ball
125
resists due to its interference fit with slot
55
. When sufficient force is imposed, ball
125
retracts into body
121
, allowing guide pin assembly
120
to pull free of slot
55
. Conversely, when moveable housing
60
is allowed to close, tension springs
80
pull moveable housing
60
forcefully against fixed housing
50
.
Beveled end
122
of guide pin assembly
120
aids in locating guide pin assembly
120
into slot
55
. Once ball
125
passes through slot
55
, it interferes against fixed housing
50
to keep moveable housing
60
closed.
FIG. 6A
shows a round shaft
100
;
FIG. 6B
shows a square shaft
300
. The components shown are designed to fit the appropriate shaft, and include retaining rings
160
,
180
, lug
170
,
370
, washer
150
,
350
, and bushings
140
,
340
,
130
,
330
. Operation of either style of shaft is identical, with the additional feature that square shaft
300
will not rotate.
In the event the door is impacted by an outside force (such as a forklift), it is pushed out in direction
40
(FIG.
2
A). This outward force bears against pin
110
and shaft
100
, which in turn bear against moveable housing
60
. When sufficient force is attained, moveable housing
60
swings free of fixed housing
50
, permitting door segment
21
to move. When the outside force is removed, the door falls back into its original position due to gravity. If door segment
21
did not move too far (as shown by open guide system
47
, FIG.
2
A), pin
110
is still riding in track
30
. Therefore, moveable housing
60
is still able to close due to the force of tension springs
80
.
If door segment
20
moved so far as to cause pin
110
to come out of track
30
(as shown by closed guide system
48
, FIG.
2
A), moveable housing
60
closes due to the force of tension springs
80
. When the door is allowed to fall back to its original position, the pin
110
associated with closed guide system
48
is bearing on the outside of track
30
instead of its normal position inside track
30
(FIG.
2
B). When this occurs, the user pulls on handle
190
, which causes shaft
100
to retract inside moveable housing
60
against compression spring
90
. When shaft
100
retracts sufficiently, pin
110
no longer bears on the outside of track
30
, and door segment
20
can move back to its normal position.
The user releases handle
190
, allowing compression spring
90
to force shaft
100
back into its normal position, and pin
110
is now back inside track
30
.
Claims
- 1. A guide system which may be applied to an existing door and track including means to guide said door during its normal operation and means to protect said overhead door in the event of an impact comprising:a fixed housing, a moveable housing, first resilient means biased to keep said fixed and said moveable housings closed, at least one projecting pin adapted to engage said track, at least one shaft, means to retain said shaft, second resilient means biased for automatically resetting said guide system; and means for manually resetting said guide system.
- 2. A guide system according to claim 1 wherein said fixed housing is adapted to be mounted to a segment of said overhead door.
- 3. A guide system according to claim 1 wherein said movable housing is attached to said fixed housing by hinge fastening means.
- 4. A guide system according to claim 1 having means to keep said fixed and movable housings closed relative to each other.
- 5. A guide system according to claim 4 wherein said means means to keep said fixed and moveable housings closed relative to each other comprise at least one guide pin.
- 6. A guide system according to claim 1 wherein said projecting pin is made of a relatively soft and slideable material which allows said projecting pin to move freely inside door tracks.
- 7. A guide system according to claim 6 wherein said relatively soft and slideable material is selected from nylon and teflon.
- 8. A guide system according to claim 1 wherein said shaft which moves inside said moveable housing, and allows said projecting pin to be manually reset into said tracks in the event the door is forced outward.
- 9. A guide system according to claim 1 wherein said means to retain said shaft bushings, a washer, and a retaining ring.
- 10. A guide system according to claim 1 wherein said second resilient means biased for automatic resetting said guide system comprise tension springs which allow said moveable housing to close with respect to said fixed housing.
- 11. A guide system according to claim 1 wherein said means for manually resetting said guide system include resetting means to manually reset the guide system if said pin no longer rides in said door track.
- 12. A guide system according to claim 11 wherein said manual resetting means comprise a handle which allows the user to pull said shaft into said moveable housing sufficiently far to allow said pin to once again ride in the door track.
- 13. A door system comprising:a guide system, and tracks for said guide system; said guide system comprising: a fixed housing, a moveable housing, resilient means biased to keep said fixed and said moveable housings closed, at least one projecting pin, at least one shaft, means to retain said shaft, means for automatically resetting said guide system; and means for manually resetting said guide system.
- 14. A door system according to claim 13 wherein said track is sufficiently deep to accept said projecting pin.
- 15. A door system according to claim 13 wherein said means to retain said shaft comprise at least one bushing, at least one washer, and at least one retaining ring.
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A |
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Feb 1997 |
A |
5638883 |
Schulte |
Jun 1997 |
A |
5927368 |
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Jul 1999 |
A |
6039106 |
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Mar 2000 |
A |
6119307 |
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A |