GB1576292A

GB1576292A - Door closer having an opening brake

Info

Publication number: GB1576292A
Application number: GB20854/77A
Authority: GB
Original assignee: Wartsila Oy AB
Current assignee: Wartsila Oy AB
Priority date: 1976-05-19
Filing date: 1977-05-18
Publication date: 1980-10-08
Also published as: FI53024C; DE2721974A1; FI53024B; SE425118B; SE7705925L

Description

(54) DOOR CLOSER HAVING AN OPENING BRAKE (71) We, Ov WARTSILA AB, a Finnish Company of Box 230, Helsinki 10, Finland, do hereby declare the invention, for which we pray that a Patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to a door closer.

In this specification the term "door closer" means a device attached, or attachable, to a door automatically to close the door after it has been opened.

Several door closers are known which are based on a pressure fluid-operated piston/spring construction, to which the movement of the door is transmitted by means of a power transmission mechanism comprising a pinion shaft, a toothed rack or the like. Some of these known door closers also have an opening brake as an auxiliary device. The object of-the opening brake is to restrict considerably higher than normal opening speeds of the door so as to prevent, for example, a blast of wind from jerking the door. Especially when used outdoors it is necessary that the opening brake construction provides adaptability and operational reliability, especially when great temperature fluctuations occur.

If for example, the opening brake stiffens in winter time and thus is not operative in windy circumstances, the door closer might break. In addition to a suitable construction, attention must also be paid to providing sufficient adjustability of the opening brake so as to make it possible to regulate operation of the opening brake according to door size and, if necessary, to temperature fluctuations, if the construction pel- se is not sufficiently operative under variable conditions.

Pn particular, insufficient adjustability of the opening brake unit, poor applicability of the construction for winter conditions or temperature fluctuations in general, as well as an inclination to break are drawbacks in all the known door closers. For example, the construction according to Finnish Patent No. 54380 does not make any provision for adjustability of the opening brake itself, apart from adjustment of a time delay device connected to the opening brake device and working when closing the door, which device has made the construction of the opening brake more complicated.The device shown in Swedish Patent Specification No. 358701, on the other hand, comprises a rather undeveloped throttle adjustment and a narrow, long throttled duct, due to which the device is particularly sensitive to temperature fluctuations and is not, therefore, suitable for all-season outdoor use.

The present invention aims to eliminate the drawbacks mentioned above from door closers with an opening brake.

According to the present invention, there is provided a door closer comprising a movable unit for forcing pressure fluid throuh a flow duct in dependence on the movement of a door adapted to be attached to said movable unit, and flow restricting means positioned within the flow duct for influencing the speed of the opening movement of a door attached to the movable unit and comprising valve means, fluid flow control means having a passage for the flow of fluid therethrough, the fluid flow control means defining with the flow duct a throttled flow duct and being movable within the flow duct between a first position preventing or restricting the flow of fluid through said throttled duct and a second position enabling, or allowing less restricted, fluid flow through said throttled duct, the valve means and the fluid flow control means being movable relative to each other into and out of a closed position in which fluid flow through said passage is prevented or substantially restricted, first spring means acting to urge the fluid flow control means and the valve means out of the said closed position, and second spring means acting to resist movement of the fluid flow control means into the said second position, whereby flow pressure, caused by movement of the movable unit, is adapted to act on the flow restricting means to move the fluid flow control means and valve means relatively to each other into said closed position, whereafter, with the fluid flow control means and valve means in said closed position and on increasing flow pressure acting on the flow restricting means, said fluid flow control means is adapted to be moved within the flow duct out of said first position and, against the force exerted by said second spring means, into said second position.

A door closer in accordance with the invention has a constructionally rather uncomplicated opening brake, the operation of which is independent of temperature fluctuations so that its operational reliability is maintained throughout the year.

As the operation of the opening brake of a door closer according to the invention is based on restricting the fluid flow, the term "flow restricting means " is used in the claims and in the description as being synonymous with the term "opening brake".

The tension of said second spring means can easily be made adjustable, for example, by arranging an adjustment screw in the body of the door closer. Also the flow restricting means may be provided with a device for adjusting the spring load of the first spring means, which device can be attached, for example by screw threads, to the body of the door closer or to another suitable member. In order to provide sufficient adjustability, the tension of both spring means can be arranged to be adjustable so that by adjusting the tension of the first spring means, the opening speed of the door which starts the braking can be determined, and the pressure determining the braking torquf can be set by adjusting the tension of said second spring means.

A door closer with an opening brake provided with this kind of adjustability can be used in doors of different sizes and under very variable conditions.

The presusre fluid flow through the throttled duct can easily be controlled either directly by arranging a stop face in the flow duct of the door closer against which said second spring means is arranged to press the fluid flow control means, or by means of the second spring means being arranged to act on the fluid flow control means through the intermediary of said valve means or some other suitable member.

If the pressure fluid flow in the throttled duct is controlled directly by the arrangement of the stop face in the flow duct, the valve can easily be located inside the fluid flow control means. The fluid flow control means may comprise a first tubular member and a second tubular member adjustably positioned within the first tubular member, the valve means being located inside the second tubular member. With regard to posisble reverse flow, the second tubular member may be provided with stop means to prevent the valve means from escaping. The valve means may be ballshaped.

An advantageous construction is obtained if the flow duct of the door closer is arranged to pass, at least partly, through the adjustment screw of said second spring means. The adjustment screw can at the same time be provided with a stop face for the fluid flow control means.

For sensing the opening speed of the door the said passage may compirse a throttled portion. Preferably this throttled portion is sharp-edged, since the function of a sharp-edged throttling member has proved to be independent of temperature and oil viscosity, so that the door closer can work outdoors in winter and summer without separate adjustment. The throttled portion can be located, for example, betweent he fluid flow control means and the valve means.

If the pressure fluid flow in the throttled duct is controlled by means of the second spring means acting on the fluid flow control means through the valve means or other member, it is of advantage if a throttled portion forms part of the fluid flow control means. The valve means can then be a plug or the like, preferably provided with a frusto-conical surface for cooperation with a frusto-conical surface defining the throttled portion of said passage.

With respect to the adjustment of the spring load of the first spring means it is of advantage if the valve means further comprises an abutment member against which said second spring means is arranged to act and which is in screw-threaded connection with the plug, so that the adjustment of the said closed position can be carried out by turning said plug relative to said abutment member.

If the tension of both spring means is to be adjusted, an adjustment device for adjusting the tension of the first spring means can be attached, for example by screwthreads, to the adjustment screw of said second spring means. Thus, by locating both adjustment devices in the body of the door closer, the adjustments can easily be carried through from outside the body of the door closer.

As the opening brake is intended to work only when the door opens, the valve means can be designed to allow fluid flow through said passage in a flow direction corresponding to the closing movement of the door.

The function of a flow restricting means with the features described above and serving as an opening brake comprises a phase just after the closing of the valve means, when pressure fluid, at least theoretically, cannot flow at all through the flow duct of the door closer. In order to soften the starting of the braking phase, the said passage and/or the throttled duct can be provided with a throttled opening, for example a groove, through which some fluid is allowed to flow during the whole working phase of the flow restricting means. In practice, clearances between the parts may serve the same purpose, depending on the construction of the opening brake.

If the opening brake is operational at small opening angles of the door, when the opening speed of the door is still rather low, the result is that when the door opens more and the opening speed of the door thus increases, the opening brake will have to operate almost constantly.

Hence, at small opening angles of the door, it may be desirable to lead at least a substantial part of the fluid flow past the flow restricting means through an auxiliary duct.

The invention will now be described in greater detail, by way of example, with reference to the accompanying drawings, in which, Figures 1 and 2 are schematic sectional views of part of a first embodiment of the invention with the opening brake in different working positions, and Figures 3 and 4, Figures 5 and 6, and Figures 7 and 8 are schematic views similar to Figures 1 and 2 of second, third and fourth embodiments of the invention, respectively.

In each of the embodiments shown in the drawings, the numeral 1 designates the body of a door closer in which a piston 3, by means of conventional rack power transmission (not shown), pumps pressure fluid in correspondence with the movements of a door through a flow duct 4 from a chamber 2a to a chamber 2b (shown only in the embodiments of Figures 3, 5 and 7) when opening the door and from the chamber 2b to the chamber 2a when dosing the door.

In Figures 1 and 2, an auxiliary duct is designated by the numeral 5 and a fluid flow control means, located in the main flow duct of the door closer, consists of a tubular element 6 and a tubular closing member 8 adjustably secured within the element 6, the element 6 and the member 8 together providing a passage through thefluid control means. The fluid flow control means is movable within the duct 4 between a first position (shown in Figure 1) and a second position (shown in Figure 2), the fluid flow control means being urged into its first position by a spring 7. The load of the spring 7 can be adjusted by an adjustment screw 11 which has screwthreaded engagement in the body 1. The member 8 provides a valve seat for valve means in the form of a ball-shaped movable closing member 9 which is loaded by a spring 10, the force of which is adjustable.

Stop means 15 retain the movable closing member 9 within the closing member 8.

The opening brake of the door closer shown in Figures 1 and 2 functions in the following way: - In the first phase of the door opening movement (phase I, Figure 1), i.e. at small opening angles of the door, the flow of pressure fluid, due to the movement of the piston 3 from the chamber 2a, is mainly through the auxiliary duct 5 into the main flow duct 4, and from there to another chamber 2b (not shown in Figures 1 and 2). In phase II of the opening movement, i.e. when the door has opened so much that the duct 5 is closed by the piston 3, the pressure fluid flows from the chamber 2a, as indicated by arrows, through the adjustment screw 11 and the flow restricting member located in the main flow duct 4, into the chamber 2b.

At ordinary opening speeds of the door no braking is effected by the flow restricting member. Under these conditions the tubular element 6 is held by the spring 7 against a surface 18 of the screw 11 and the closing member 9 is in the position shown in Figure 1. As the opening speed of the door increase, the flow resistance in the annular slot between the moving closing member 9 and the closing member 8 increases, and the pressure of the fluid increases upstream of the member 9.

When this pressure exceeds the force of the spring 10, the member 9 moves into its position shown in Figure 2, causing the flow of fluid through the said passage to be shut off thereby braking thet opening movement of the door. The pressure upstream of the member 9 acts also on the fluid flow control means and urges the element 6 against the forces of the spring 7 which at this stage, is still pressing the element 6 against the surface 18. When the pressure increases further, the element 6 compresses the spring 7 and moves to the position shown in Figure 3 so that pressure fluid can flow through a throttled duct 13 (phase III), defined between the flow duct 4 and the element 6.

In this embodiment, throttling condi tions actually prevail only in a narrow and short throttled passage 14 of the throttled duct 13, which damps the vibrations of the fluid flow control means and makes the flow less dependent on temperature fluctuations. A throttled opening 16 (which is in the form of a groove in Figures 1 and 2) between the element 6 and the surface 18 allows some pressure fluid to flow during the whole working phase of the opening brake, which soften the start of the braking performance.

The opening speed of the door, at which braking begins, is adjustable by changing the load of spring 10. In the embodiment of Figures 1 and 2 this is accomplished by axial adjustment of the closing member 8 which respect to the element 6. In the embodiment shown the closing member 8 is screw-threaded into the element 6, so that axial adjustment of the closing member 8 is effected by turning it relative to the element 6. The braking pressure is adjustable by changing the load of the spring 7 of the piston member by means of the adjustment screw 11. The location of the auxiliary duct 5 in the moving direction of the piston 3 determines when the pressure fluid flow passes only through the flow re stricting member and, consequently, when the flow restricting member is operative.

As a rule, the auxiliary duct 5 is located so that the operative phase of the flow restricting member starts from 50O to 10 before the intended open position of the door. Especially if the door opens only through 90 , the operative phase starts when the door is opened from 50O to 80 , usually from 60 to 70".

The manner in which the embodiment shown in Figures 3 and 4 operates corresponds fundamentally to that of the embodiment of Figures 1 and 2, but some constructional differences exist. As a sensor for the opening speed of the door there is, in the flow duct of the valve, a sharp-edged throttled passage 17 in the movable closing member 9 of the valve, the function of this passage being independent of temperature and oil viscosity, has has been mentioned before. The fluid flow control means is constituted by the tubular element 6 alone and the adjustment of the load of both of the springs 7 and 10 can be accomplished directly from outside the body of the door closer by the adjustment screws 11 and 12 which are in screw-threaded connection with each other. A stop face 18 for the element 6 is arranged in the body of the door closer by suitable shaping of the flow duct 4.Further, the location of the auxiliary duct 5, to connect directly the chambers 2a and 2b and to form a duct independent of the flow duct 4, differs from the previous embodiment, as does the use of a ball 19 in said auxiliary duct 5. The throttled opening 16 can be used to damp pressure increase and braking, but the mere clearances of the flow restricting assembly can as well be used for the same purpose.

In the embodiment according to Figures 5 and 6, the valve means is constituted by the closing member 8 in the form of a plug having screw-threaded connection with an element 6. The fluid flow control means is constituted by a tubllar or cup-shaped member 9 having a sharp-edged throttled passage 17 through which the pressure fluid flow is led and which passage serves as a sensor for the opening movement of the door. When the valve means closes, the throttled passage 17 also serves as the sealing surface of the valve means, wherein a throttled opening 16 may be arranged if desired. Adjustment of the starting point of the braking is effected by axial adjustment of the closing member 8 by rotating it relative to the element 6.In other respects the construction is similar to the embodiment according to Figures 3 and 4 and the main functional principles correspond to those described above.

In the embodiment shown in Figures 7 and 8, the valve means is constituted by an element 6. The fluid flow control means is constituted by a member 9 shaped as in the embodiment of Figures 5 and 6, but the throttled passage 17 and the sealing surface of the valve means are separated from one another. The adjustment of the spring 10 loaded by the member 9 is performed by the adjustment screw 12, which is in screw-threaded connection with the adjustment screw 11, and which is a close fit in the opening 20 of the element 6, but nevertheless movable with respect to the element 6. In other respects the construction corresponds to that shown in Figures 1 and 2 and the main functional principles are similar to those of the other embodi ments of the invention.

WHAT WE CLAIM IS: - 1. A door closer comprising a movable unit for forcing pressure fluid through a flow duct in dependence on the movement of a door adapted to be attached to said movable unit, and flow restricting means positioned within the flow duct for in fluencing the speed of the opening movement of a door attached to the movable unit and comprising valve means, fluid flow control means having a passage for the flow of fluid therethrough, the fluid flow control means defining with the flow duct a throttled flow duct and being movable within the flow duct between a first portion preventing or restricting the flow of fluid through said throttled duct and a second position enabling, or allowing less re

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. tions actually prevail only in a narrow and short throttled passage 14 of the throttled duct 13, which damps the vibrations of the fluid flow control means and makes the flow less dependent on temperature fluctuations. A throttled opening 16 (which is in the form of a groove in Figures 1 and 2) between the element 6 and the surface 18 allows some pressure fluid to flow during the whole working phase of the opening brake, which soften the start of the braking performance. The opening speed of the door, at which braking begins, is adjustable by changing the load of spring 10. In the embodiment of Figures 1 and 2 this is accomplished by axial adjustment of the closing member 8 which respect to the element 6. In the embodiment shown the closing member 8 is screw-threaded into the element 6, so that axial adjustment of the closing member 8 is effected by turning it relative to the element 6. The braking pressure is adjustable by changing the load of the spring 7 of the piston member by means of the adjustment screw 11. The location of the auxiliary duct 5 in the moving direction of the piston 3 determines when the pressure fluid flow passes only through the flow re stricting member and, consequently, when the flow restricting member is operative. As a rule, the auxiliary duct 5 is located so that the operative phase of the flow restricting member starts from 50O to 10 before the intended open position of the door. Especially if the door opens only through 90 , the operative phase starts when the door is opened from 50O to 80 , usually from 60 to 70". The manner in which the embodiment shown in Figures 3 and 4 operates corresponds fundamentally to that of the embodiment of Figures 1 and 2, but some constructional differences exist. As a sensor for the opening speed of the door there is, in the flow duct of the valve, a sharp-edged throttled passage 17 in the movable closing member 9 of the valve, the function of this passage being independent of temperature and oil viscosity, has has been mentioned before. The fluid flow control means is constituted by the tubular element 6 alone and the adjustment of the load of both of the springs 7 and 10 can be accomplished directly from outside the body of the door closer by the adjustment screws 11 and 12 which are in screw-threaded connection with each other. A stop face 18 for the element 6 is arranged in the body of the door closer by suitable shaping of the flow duct 4.Further, the location of the auxiliary duct 5, to connect directly the chambers 2a and 2b and to form a duct independent of the flow duct 4, differs from the previous embodiment, as does the use of a ball 19 in said auxiliary duct 5. The throttled opening 16 can be used to damp pressure increase and braking, but the mere clearances of the flow restricting assembly can as well be used for the same purpose. In the embodiment according to Figures 5 and 6, the valve means is constituted by the closing member 8 in the form of a plug having screw-threaded connection with an element 6. The fluid flow control means is constituted by a tubllar or cup-shaped member 9 having a sharp-edged throttled passage 17 through which the pressure fluid flow is led and which passage serves as a sensor for the opening movement of the door. When the valve means closes, the throttled passage 17 also serves as the sealing surface of the valve means, wherein a throttled opening 16 may be arranged if desired. Adjustment of the starting point of the braking is effected by axial adjustment of the closing member 8 by rotating it relative to the element 6.In other respects the construction is similar to the embodiment according to Figures 3 and 4 and the main functional principles correspond to those described above. In the embodiment shown in Figures 7 and 8, the valve means is constituted by an element 6. The fluid flow control means is constituted by a member 9 shaped as in the embodiment of Figures 5 and 6, but the throttled passage 17 and the sealing surface of the valve means are separated from one another. The adjustment of the spring 10 loaded by the member 9 is performed by the adjustment screw 12, which is in screw-threaded connection with the adjustment screw 11, and which is a close fit in the opening 20 of the element 6, but nevertheless movable with respect to the element 6. In other respects the construction corresponds to that shown in Figures

1 and 2 and the main functional principles are similar to those of the other embodi ments of the invention.

stricted, fluid flow through said throttled duct, the valve means and the fluid flow control means being movable relative to each other into and out of a closed position in which fluid flow through said passage is prevented or substantially restricted, first spring means acting to urge the fluid flow control means and the valve means out of the said closed position, and second spring means acting to resist movement of the fluid flow control means into the said second position, whereby flow pressure, caused by movement of the movable unit, is adapted to act on the flow restricting means to move the fluid flow control means and valve means relatively to each other into said closed position, whereafter, with the fluid flow control means and valve means in said closed position and on increasing flow pressure acting on the flow restricting means, said fluid flow control means is adapted to be moved within the flow duct out of said first position and, against the force exerted by said second spring means, into said second position.

2. A door closer according to claim 1, in which the tension of said second spring means is adjustable.

3. A door closer according to claim 2, in which the body of the door closer is provided with an adjustment screw influencing the tension of said second spring means.

4. A door closer according to claim 1, in which the spring load of the first spring means is adjustable.

5. A door closer according to claim 4, in which the flow restricting means is provided with a device for adjusting the spring load of the first spring means, said device being attached, preferably by screw-threads, to the body of the door closer or to another suitable member.

6. A door closer according to any of the preceding claims, in which the tension of both said spring means is adjustable.

7. A door closer according to any of the preceding claims, in which in order to control the pressure fluid flow through the throttled duct, the flow duct of the door closer is provided with a stop face against which said second spring means is arranged to press the fluid flow control means.

8. A door closer according to any of the preceding claims, in which the valve means is located inside the fluid flow control means.

9. A door closer according to any of the preceding claims, in which the fluid flow control means comprises a first tubular member and a second tubular member adjustably positioned within the first tubular member, the valve means being located inside said second tubular member.

10. A door closer according to claim 9, in which the second tubular member is provided with stop means to prevent the valve means from escaping.

11. A door closer according to any of the preceding claims, in which the valve means is ball-shaped.

12. A door closer according to claim 7 when dependent on claim 3 and any of claims 8 to 11 when dependent on claim 7 and claim 3, in which the flow duct of the door closer is arranged to pass, at least partly, through the adjustment screw of said second spring means, said adjustment screw being provided with said stop face for the fluid flow control means.

13 A door closer according to any of claims 1 to 6, in which the said passage comprises a preferably sharp-edged throttled portion.

14. A door closer according to claim 13, in which the said throttled portion is arranged between the fluid flow control means and the valve means.

15. A door closer according to any of claims 1 to 6 or 13, in which the second spring means is arranged to act on the fluid flow control means through the intermediary of said valve means or some other suitable member.

16. A door closer according to claim 13 or 15, in which the said throttled portion forms part of the fluid flow control means.

17. A door closer according to claim 16, in which the valve means comprises a plug adapted when in said closed position to block or substantially restrict the flow of fluid through said throttled portion.

18. A door closer according to claim 17, in which said plug is provided with a frusto-conical surface or cooperation with a frusto-conical surface defining the throttled portion of said passage.

19. A door closer according to any of claims 16 to 18, in which the valve means further comprises an abutment member against which said second spring means is arranged to act in screw-threaded connection with the plug, whereby adjustment of the said closed position is carried out by turning said plug relative to said abutment member.

20. A door closer according to claim 3, in which an adjustment device for adjusting the tension of said first spring means is attached, preferably by screw-threads, to the adjustment screw of said second spring means.

21. A door closer according to any of claims 1 to 3, in which the adjustment devices of both of said spring means are located in the body of the door closer.

22. A door closer according to any of the preceding claims, in which the valve means is arranged to allow fluid flow through said passage in the flow direction corresponding to the closing movement of the door.

23. A door closer according to any of the preceding claims, in which the passage and/or the throttled duct is provided with a throttled opening or the like, through which some fluid is allowed to flow during the whole working phase of the flow restricting means.

24. A door closer according to any of the preceding claims, in which, at small opening angles of the door, at least a substantial part of the fluid flow is led past the flow restricting means through an auxiliary duct.

25. A door closer constructed and arranged substantially as herein described with reference to, and as illustrated in, Figures 1 and 2, Figures 3 and 4, Figures 5 and 6 or Figures 7 and 8 of the accompanying drawings.

26. A door fitted with a door closer according to any of the preceding claims.