CA1111296A - Gate assembly with automatic opening and closing mechanism - Google Patents
Gate assembly with automatic opening and closing mechanismInfo
- Publication number
- CA1111296A CA1111296A CA325,927A CA325927A CA1111296A CA 1111296 A CA1111296 A CA 1111296A CA 325927 A CA325927 A CA 325927A CA 1111296 A CA1111296 A CA 1111296A
- Authority
- CA
- Canada
- Prior art keywords
- gate
- abutment
- support roller
- cam track
- pole
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Landscapes
- Refuge Islands, Traffic Blockers, Or Guard Fence (AREA)
Abstract
ABSTRACT
An arrangement in a gate (10) wherein a cam track (23) is provided for lifting the gate on the pivot axis (12) thereof when the gate is being swung to opened position. An abutment (34) is provided in the cam track for a member (18) connected with the gate. The abutment is arranged to maintain the position in the cam track when the gate is being swung to opened position and is arranged for delayed yielding under the pressure exerted against the abutment by the gate (10) over the member when the gate is in opened position and is lifted by the cam track.
An arrangement in a gate (10) wherein a cam track (23) is provided for lifting the gate on the pivot axis (12) thereof when the gate is being swung to opened position. An abutment (34) is provided in the cam track for a member (18) connected with the gate. The abutment is arranged to maintain the position in the cam track when the gate is being swung to opened position and is arranged for delayed yielding under the pressure exerted against the abutment by the gate (10) over the member when the gate is in opened position and is lifted by the cam track.
Description
2~i The present inven-tion relates to a gate assembly haviny a vertical ga-te pole, a gate pivotable about and ver-ti-cally displaceable along said pole, and a mechanism for auto-matically opening and closiny the date comprising a gate-suppor-ting roller which rests on a stationary cam -track having a lowermost point which determines a res-t position of the yate correspondiny to the closed position thereof, said track climbiny on at leas-t one side of said point in order that the yate when swuny from the closed position shall be returned by yravity to the closed position by the support roller rolliny down the cam track, an abutment which is movable between a position obstructing the path of the support roller along the cam track, in which position it allows movement of the support roller over the abut-ment in a direction away from the rest position but prevents the support roller from returning to the rest position, and another position in which the abutment to a ma~or part is removed from the path of the support roller in order to allow the support roller to return along the cam track to the rest position.
GB-A-481,285 describes a gate assembly of the type referred to wherein the gate is swung to opened position by ::
being pushed out of the way by a vehicle which presses against the gate, and then automatically swinys back to the closed position thereof when the vehicle has passed throuyh the gate openiny. In this prior art yate assembly the abutment comprises a pivoted cam. During the opening movement of the gate the roller moves on-to the cam from one side of the pivot axis thereof .
and then the cam pivots when the gate is substan-tially in a ~S pOSitiOII to .Illow the roller to move downwards alony the cam at the other side of the pivot axis, the yate thereby moviny to opened position. Then, the yate returns to the closed position, the abutment beiny displaced from the path of the roller.
A drawback of -this prior art yate is that it re-turns ~ 3L2~
tso rapidly to th~ closed position thereof so that there is a risk that the vehicle passing through the gate opening rubs the slde ayainst the gate whereby the gate can yet caught on the vehicle or can cause damage thereon.
For the purpose of eliminating this drawback and pro-~iding a gate with delayed return in order that the gate shall remain in the opened position during the time necessary for the vehicle to pass through the gate opening, the invention provides a gate assembly o~ the type referred to above characterized by spring means having a damper allowing the abutment to be slowly removed from the path of the support roller along the cam track against the spring bias under the pressure of the support roller against the abutment and to be rapidly returned by the spring bia,s to the position in which it obstructs the path of the support roller along the cam track when the roller has passed the abutment.
In order to illustrate the invention, an embodiment thereof will be described in more detail below with reference to the accompanying.drawing in which FigO 1 i6 a side view of a gate arranged according to the invention, and ~
~ - .
'~ ' .
~ 1.
.
- la -, ...................................... . .
~iL~2~
FIG. 2 is an enlarged perspective view of the arrangement according to the invention.
The gate of FIG. 1 comprises a tube construction 10 which is journalled by mean~ of a vertical tube 11 on a gate pole 12. The gate has vertical tubes 13 suitably spaced in order that a vehicle which moves towards the gate shall hit the gate with the bumper thereof at these tubes and push the gate out of the way from the closed position ~hereof when the vehicle is moving through the gate opening.
As will be seen from FIG. 2, the gate tube 11 is journalled on the tubular gate pole 12 by means of bushings 14 which can be provided at top and bottom in the tube 11 and possibly at one or more positions therebetween. The gate tube 11 is not only pivoting but also displaceable vertically on the gate pole 12, and one or more grease fittings 15 are provided for lubricat- ¦~
ing the bearings between the gate tube and the gate pole 50 that the gate tube runs easily on the gate pole.
At the top, the gate tube 11 is closed by a cover 16 which can be secured by means of a lock bolt 17 or the like. i~-On the inner side of th~ gate tube 11 there is pivotally mounted a support roller 18 formed as a ball bearing roller with a trunnion 19 secured by a screw connection 20 to the gate tube. The screw connection is covered externally by a metal sheet casing 21. The support roller 18 is received by an opening 22 in the gate pole 12, and the lower edge of this opening forms a cam track 23 climbing progressively in the direction of the arrow 24 from the position of the support roller 18, shown to the right in FIG. 2. Said position of the support roller 18 corresponds to the closed position of the gate 10. , Inside the gate pole a tubular element 25 is mounted for axial displacement, and this element is non-rotatably guided by m~ans of an axiallv extending rib 26 fixedly arranged inside the gate pole 12. By means of a bracket 27 having a socket 28 at the outer end thereof the element 25 is secured to the piston rod 29 of a hydraulic ram 30 by means of a screw connection 31, and the ram 30 is connected at the upper end thereof to a ring or plate 32 which in turn ls secured to the gate pole 12 by means of a screw connection 33. The hydraulic ram 30 is of the type (shock absorber) having a spring which biases the piston of the hydraulic ram in one direction which is assumed to correspond in the present case to dis~lace-ment of the piston rod 29 in upward direction. Further-more, the piston of the hydraulic ram 30 has a valvecontrolled connection between the cylinder spaces filled with hydraulic fluid on each side of the piston, said connection being of the kind allowing fluid to pass between the opposite sides oE the piston when the piston is displaced upwardly under the bias of the spring while the flow of the fluitl is choked when the piston is displaced downwardly in the cylinder against the bias of the spring.
The element 25 forms a crest 34 having a gently sloping ramp 35 and a steeper ramp 36, and under the bias of the spring in the hydraulic ram 30 this crest is located in the path of the support roller 18 along the cam track 23 as is shown in FIG. 2, the crest 34 projecting upwardly from the cam track 23 as a nose.
The crest is kept in this position by the spring and it can be depressed from said position by a slow motion only against the bias of the spring because the choked flow of hydraulic fluid between the opposite sides of the piston retards such depression. The piston has a stroke which is large enough for the crest to be depressed sufficiently to a position wherein it is flush with the cam track ~3, or at least to a position wherein the crest projects slightly from this cam track. However, when the pressure against the crest 34 is relie~ed, the crest will rapidly return to the position shown under the bias of the spring in the hydraulic ram 30 because the fluid can then pass rapidly from one side of the piston to the other side thereof.
If the gate is swung towards opened position according to the arrow in FIG. 1 by a vehicle being driven against the gate and pushing this out of the way, this means that the support roller 1~ rolls in the direction of the arrow 24, the roller being lifted from tha cam track 23 when it is rolling upwards the ramp 36 on the crest 34 in order to roll thereafter onto the cam track 23 again along the ramp 35. During this movement the gate i5 thus lifted, the gate tube 11 being displaced vertically on the gate pole 12, and since the oil in the hydraulic ram 30 by the choking action in the valve controlled opening in the piston retards the movement downwards of the crest 34, this crest will not be depressed when the support roller 18 is moving over same. Some small depression may of course occur at the passage of the roller but it is of no significance. The support roller 18 will be caught by the crest 34 at the side of the crest where the ramp 35 is provided, and will now be in the position 18' as indicated by ~ash and dot lines, in which the gate is fully opened and thus is swung substantially 90 or preferably more than 90 from the position shown in FIG. 1. Having passed the top of the crest 34 the support roller 18 will roll down the ramp 35 under the weight of the gate so that the gate as a consequence thereof will be swung automa-tically to ,., opened position without the vehicle pushing against the gate. This automatic swinging can begin in a 45 to 60 position of the gate. Resting against the cam track 23 and against the ramp 35 the support roller 18 will cause a pressure against the crest 34 in the position 18l, said pressure being dependent on the weight of the gate, and ~he crest will then move slowly downwards against the bias of the spring provided in the ram 30, as allowed by the flow of hydraulic fluid between the two sides of the piston through the cho~ed opening therein. Eventually, th~
crest 34 will reach a position in which the support roller 18 can roll along the cam track 23 back to the position shown by solid lines in FIG. 2. By adapting the choking in the piston and the inclination angles ; of the cam track 23 and the ramp 36 in a suitable way in relation to the weight of the gate it is possible to adapt, as desired, the time it takes for the gate to depress the crest 34 when the gate is in the opened position in order that the gate shall then be able to swing to the closed position thereof. As soon as the support roller 18 has passed the depressed crest 34 when the gate is moving from opened position to closed position the spring of the hydraulic ram 30 will rapidly press the crest 34 upwards to the position shown because such movement is not prevented to a significant extent by the fluid in the hydraulic ram.
Then the gate is ready to be opened again in the manner described.
Thus, it will be seen that by the arrangement according to the inven-tion the gate will be swung automatically to the opened position when such movement has been initiated by a vehicle moving against the gate and pushing it out of the way, and the gate will also be securely retained in the opened position thereof in ~.
6 ~ 2~
order that the gate shall return after a delay to the closed position thereof. Moreover, it is possible to adapt the delay in such a manner that the gate will be ; maintained in the opened position long enough for a vehicle of maximum length to pass through the gate opening at a low speed.
As described above, the arrangement allows the gate to be swung towards one side only, but of course it is possible to provide the element 25 with two diametrically opposite crests 34 and to make the opening 22 in the gate pole sufficiently large so that the gate can be swung towards one side or the other from a rest position in which the gate is closed and will be retained for delayed return independently of the gate being swung towards one side or the other. The same element 25 and the same hydraulic ram 30 can control the delay towards bcth sides.
The invention is not, of course, limited to the embodiment shown but can be designed in other ways within the scope of the accompanying claims. This is true e.g. for the arrangement of the hydraulic ram 30 which is shown in a suspended position but can be arranged also in a standing position inside the gate pole 12. It is also possible to let the ram 30 move together with the element 25 while the piston rod 29 is fixedly secured to the gate pole 12~ Moreover, the element 25 can be arranged in different ways but the tubular embodiment shown herein would be preferred con~
sidering that the eleme~t thereby can be guided in a relatively simple manner. The spring can be arranged outside the cylinder instead of being located inside the cylinder as has been said to be the case in the `
embodiment shown.
~,. ..
'.1 ~,
GB-A-481,285 describes a gate assembly of the type referred to wherein the gate is swung to opened position by ::
being pushed out of the way by a vehicle which presses against the gate, and then automatically swinys back to the closed position thereof when the vehicle has passed throuyh the gate openiny. In this prior art yate assembly the abutment comprises a pivoted cam. During the opening movement of the gate the roller moves on-to the cam from one side of the pivot axis thereof .
and then the cam pivots when the gate is substan-tially in a ~S pOSitiOII to .Illow the roller to move downwards alony the cam at the other side of the pivot axis, the yate thereby moviny to opened position. Then, the yate returns to the closed position, the abutment beiny displaced from the path of the roller.
A drawback of -this prior art yate is that it re-turns ~ 3L2~
tso rapidly to th~ closed position thereof so that there is a risk that the vehicle passing through the gate opening rubs the slde ayainst the gate whereby the gate can yet caught on the vehicle or can cause damage thereon.
For the purpose of eliminating this drawback and pro-~iding a gate with delayed return in order that the gate shall remain in the opened position during the time necessary for the vehicle to pass through the gate opening, the invention provides a gate assembly o~ the type referred to above characterized by spring means having a damper allowing the abutment to be slowly removed from the path of the support roller along the cam track against the spring bias under the pressure of the support roller against the abutment and to be rapidly returned by the spring bia,s to the position in which it obstructs the path of the support roller along the cam track when the roller has passed the abutment.
In order to illustrate the invention, an embodiment thereof will be described in more detail below with reference to the accompanying.drawing in which FigO 1 i6 a side view of a gate arranged according to the invention, and ~
~ - .
'~ ' .
~ 1.
.
- la -, ...................................... . .
~iL~2~
FIG. 2 is an enlarged perspective view of the arrangement according to the invention.
The gate of FIG. 1 comprises a tube construction 10 which is journalled by mean~ of a vertical tube 11 on a gate pole 12. The gate has vertical tubes 13 suitably spaced in order that a vehicle which moves towards the gate shall hit the gate with the bumper thereof at these tubes and push the gate out of the way from the closed position ~hereof when the vehicle is moving through the gate opening.
As will be seen from FIG. 2, the gate tube 11 is journalled on the tubular gate pole 12 by means of bushings 14 which can be provided at top and bottom in the tube 11 and possibly at one or more positions therebetween. The gate tube 11 is not only pivoting but also displaceable vertically on the gate pole 12, and one or more grease fittings 15 are provided for lubricat- ¦~
ing the bearings between the gate tube and the gate pole 50 that the gate tube runs easily on the gate pole.
At the top, the gate tube 11 is closed by a cover 16 which can be secured by means of a lock bolt 17 or the like. i~-On the inner side of th~ gate tube 11 there is pivotally mounted a support roller 18 formed as a ball bearing roller with a trunnion 19 secured by a screw connection 20 to the gate tube. The screw connection is covered externally by a metal sheet casing 21. The support roller 18 is received by an opening 22 in the gate pole 12, and the lower edge of this opening forms a cam track 23 climbing progressively in the direction of the arrow 24 from the position of the support roller 18, shown to the right in FIG. 2. Said position of the support roller 18 corresponds to the closed position of the gate 10. , Inside the gate pole a tubular element 25 is mounted for axial displacement, and this element is non-rotatably guided by m~ans of an axiallv extending rib 26 fixedly arranged inside the gate pole 12. By means of a bracket 27 having a socket 28 at the outer end thereof the element 25 is secured to the piston rod 29 of a hydraulic ram 30 by means of a screw connection 31, and the ram 30 is connected at the upper end thereof to a ring or plate 32 which in turn ls secured to the gate pole 12 by means of a screw connection 33. The hydraulic ram 30 is of the type (shock absorber) having a spring which biases the piston of the hydraulic ram in one direction which is assumed to correspond in the present case to dis~lace-ment of the piston rod 29 in upward direction. Further-more, the piston of the hydraulic ram 30 has a valvecontrolled connection between the cylinder spaces filled with hydraulic fluid on each side of the piston, said connection being of the kind allowing fluid to pass between the opposite sides oE the piston when the piston is displaced upwardly under the bias of the spring while the flow of the fluitl is choked when the piston is displaced downwardly in the cylinder against the bias of the spring.
The element 25 forms a crest 34 having a gently sloping ramp 35 and a steeper ramp 36, and under the bias of the spring in the hydraulic ram 30 this crest is located in the path of the support roller 18 along the cam track 23 as is shown in FIG. 2, the crest 34 projecting upwardly from the cam track 23 as a nose.
The crest is kept in this position by the spring and it can be depressed from said position by a slow motion only against the bias of the spring because the choked flow of hydraulic fluid between the opposite sides of the piston retards such depression. The piston has a stroke which is large enough for the crest to be depressed sufficiently to a position wherein it is flush with the cam track ~3, or at least to a position wherein the crest projects slightly from this cam track. However, when the pressure against the crest 34 is relie~ed, the crest will rapidly return to the position shown under the bias of the spring in the hydraulic ram 30 because the fluid can then pass rapidly from one side of the piston to the other side thereof.
If the gate is swung towards opened position according to the arrow in FIG. 1 by a vehicle being driven against the gate and pushing this out of the way, this means that the support roller 1~ rolls in the direction of the arrow 24, the roller being lifted from tha cam track 23 when it is rolling upwards the ramp 36 on the crest 34 in order to roll thereafter onto the cam track 23 again along the ramp 35. During this movement the gate i5 thus lifted, the gate tube 11 being displaced vertically on the gate pole 12, and since the oil in the hydraulic ram 30 by the choking action in the valve controlled opening in the piston retards the movement downwards of the crest 34, this crest will not be depressed when the support roller 18 is moving over same. Some small depression may of course occur at the passage of the roller but it is of no significance. The support roller 18 will be caught by the crest 34 at the side of the crest where the ramp 35 is provided, and will now be in the position 18' as indicated by ~ash and dot lines, in which the gate is fully opened and thus is swung substantially 90 or preferably more than 90 from the position shown in FIG. 1. Having passed the top of the crest 34 the support roller 18 will roll down the ramp 35 under the weight of the gate so that the gate as a consequence thereof will be swung automa-tically to ,., opened position without the vehicle pushing against the gate. This automatic swinging can begin in a 45 to 60 position of the gate. Resting against the cam track 23 and against the ramp 35 the support roller 18 will cause a pressure against the crest 34 in the position 18l, said pressure being dependent on the weight of the gate, and ~he crest will then move slowly downwards against the bias of the spring provided in the ram 30, as allowed by the flow of hydraulic fluid between the two sides of the piston through the cho~ed opening therein. Eventually, th~
crest 34 will reach a position in which the support roller 18 can roll along the cam track 23 back to the position shown by solid lines in FIG. 2. By adapting the choking in the piston and the inclination angles ; of the cam track 23 and the ramp 36 in a suitable way in relation to the weight of the gate it is possible to adapt, as desired, the time it takes for the gate to depress the crest 34 when the gate is in the opened position in order that the gate shall then be able to swing to the closed position thereof. As soon as the support roller 18 has passed the depressed crest 34 when the gate is moving from opened position to closed position the spring of the hydraulic ram 30 will rapidly press the crest 34 upwards to the position shown because such movement is not prevented to a significant extent by the fluid in the hydraulic ram.
Then the gate is ready to be opened again in the manner described.
Thus, it will be seen that by the arrangement according to the inven-tion the gate will be swung automatically to the opened position when such movement has been initiated by a vehicle moving against the gate and pushing it out of the way, and the gate will also be securely retained in the opened position thereof in ~.
6 ~ 2~
order that the gate shall return after a delay to the closed position thereof. Moreover, it is possible to adapt the delay in such a manner that the gate will be ; maintained in the opened position long enough for a vehicle of maximum length to pass through the gate opening at a low speed.
As described above, the arrangement allows the gate to be swung towards one side only, but of course it is possible to provide the element 25 with two diametrically opposite crests 34 and to make the opening 22 in the gate pole sufficiently large so that the gate can be swung towards one side or the other from a rest position in which the gate is closed and will be retained for delayed return independently of the gate being swung towards one side or the other. The same element 25 and the same hydraulic ram 30 can control the delay towards bcth sides.
The invention is not, of course, limited to the embodiment shown but can be designed in other ways within the scope of the accompanying claims. This is true e.g. for the arrangement of the hydraulic ram 30 which is shown in a suspended position but can be arranged also in a standing position inside the gate pole 12. It is also possible to let the ram 30 move together with the element 25 while the piston rod 29 is fixedly secured to the gate pole 12~ Moreover, the element 25 can be arranged in different ways but the tubular embodiment shown herein would be preferred con~
sidering that the eleme~t thereby can be guided in a relatively simple manner. The spring can be arranged outside the cylinder instead of being located inside the cylinder as has been said to be the case in the `
embodiment shown.
~,. ..
'.1 ~,
Claims (6)
1. A gate assembly having a vertical gate pole, a gate pivotable about and vertically displaceable along said pole, and a mechanism for automatically opening and closing the gate comprising a gate-supporting roller which rests on a stationary cam track having a lowermost point which determines a rest position of the gate corresponding to the closed position thereof, said track climbing on at least one side of said point in order that the gate when swung from the closed position shall be returned by gravity to the closed position by the support roller rolling down the cam track, an abutment which is movable between a position obstructing the path of the support roller along the cam track, in which position it allows movement of the support roller over the abutment in a direction away from the rest position but prevents the support roller from returning to the rest position, and another position in which the abutment to a major part is removed from the path of the support roller in order to allow the support roller to return along the cam track to the rest position, characterized by spring means having a damper allowing the abutment to be slowly removed from the path of the support roller along the cam track against the spring bias under the pressure of the support roller against the abutment and to be rapidly returned by the spring bias to the position in which it obstructs the path of the support roller along the cam track when the roller has passed the abutment.
2. A gate assembly according to claim 1, characterized in that the abutment is formed as a crest having a gently sloping ramp facing away from the rest position, and a steep ramp facing the rest position.
3. A gate assembly according to claim 1, characterized in that the damper of the spring means comprises a hydraulic ram having a check valve controlled passage between the two sides of the piston allowing rapid flow of hydraulic fluid between the cylinder spaces on opposite sides of the piston, in one direction corresponding to the return of the abutment under the spring bias, and slow flow of hydraulic fluid in the other direction corresponding to the depression of the abutment under the pres-sure of the support rolller against the abutment.
9. A gate assembly according to claim 1, characterized in that the gate pole is tubular and the cam track is formed by the edge of an opening in the gate pole.
5. A gate assembly according to claims 1, 2 or 3, characterized in that the abutment is formed by a tubular element guided for axial displacement in the tubular gate hole pole.
6. A gate assembly according to claim 3, characterized in that one part of the hydraulic ram, the cylinder or the piston, is fixedly connected to the gate pole, the other part being connected to the abutment.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA325,927A CA1111296A (en) | 1979-04-19 | 1979-04-19 | Gate assembly with automatic opening and closing mechanism |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA325,927A CA1111296A (en) | 1979-04-19 | 1979-04-19 | Gate assembly with automatic opening and closing mechanism |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1111296A true CA1111296A (en) | 1981-10-27 |
Family
ID=4114016
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA325,927A Expired CA1111296A (en) | 1979-04-19 | 1979-04-19 | Gate assembly with automatic opening and closing mechanism |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA1111296A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111395223A (en) * | 2020-04-17 | 2020-07-10 | 孙雪标 | Barrier gate capable of flexibly moving position |
-
1979
- 1979-04-19 CA CA325,927A patent/CA1111296A/en not_active Expired
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111395223A (en) * | 2020-04-17 | 2020-07-10 | 孙雪标 | Barrier gate capable of flexibly moving position |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |