HK1097583B - Improved arrangement in a swing door apparatus provided with a door closer - Google Patents

Description

Improved device for swing door equipment provided with door closer

The invention relates to a device according to the preamble of claim 1.

In automatic swing door apparatuses, the opening of the door is driven by a motor or other suitable actuator. It is advantageous to combine a door closer, the piston member of which is driven by a drive shaft which rotates in accordance with the movement of the door, with the swinging door apparatus. Since the operation of the door closer is usually based on a return spring which is compressed when the door is opened, the closing of the door can be driven by means of said spring without the above-mentioned actuator, even in a swinging door device. In this way, the cost of the use of the actuator can be saved. One problem here is that the closing of the door, especially in the case of a power failure, should be done with as low a resistance as possible, so that it is possible to ensure closing in all cases. If the pressure of the spring in the door closer is used for other purposes than for moving the door itself and the piston associated with its movement, this may result in the need to use a stiffer spring, which affects the space and cost requirements, and requires a more powerful actuator which compresses the spring to close the door when it is opened.

To provide drive from the actuator to the drive shaft, a ball screw arrangement or a combination of a worm shaft and drive nut may be advantageously used. It is therefore necessary to ensure that the worm shaft is not allowed to move in the axial direction due to the movement of the door and/or the operation of the door closer.

As regards the prior art reference is made to document GB 2020734 a, from which it is known per se to use a combination of a worm shaft and a drive nut to provide drive from an actuator to a drive shaft connected to a door. Overall, the solution is complex and takes up much space.

It is an object of the present invention to eliminate the drawbacks related to the prior art and to provide a simple and reliable solution to the above-mentioned problems.

The object of the invention is achieved in a manner which is specified in claim 1 and in the other claims. According to the present invention, the worm shaft includes a worm portion and a shaft portion integral therewith and provided with a flange portion, which is fitted with the thrust bearing means, thereby preventing the worm shaft from moving in the axial direction relative to the door closer body. Furthermore, coupling means are provided between the operating shaft of the actuator and the shaft portion of the worm shaft, which coupling means are arranged to disconnect the force transmission connection between the actuator and the shaft portion of the worm shaft and to provide said force transmission connection in order to accomplish the opening movement of the door.

By means of the coupling device it is ensured that the actuator and the gear possibly connected thereto are in operation only when the door is opened, so that, in the closing phase of the door, in the same way as in a conventional door closer, the pressure of the spring in the door closer is required only for moving the door, and the piston device in force-transmitting relationship therewith. Similarly, the movement of the worm shaft can be ensured in a simple manner without any movement in the axial direction by the flange portion and the thrust bearing cooperating therewith.

In fact, according to a preferred embodiment, one end of the drive nut is connected to the piston member and the other end is adapted to be coupled to one end of the return spring of the door closer. In this way a solution with a simple structure is provided.

The helix angle of the worm shaft and the worm portion of the drive nut is selected to be sufficiently large, for example at least 26, and preferably about 32-40, so that their reciprocal engagement is nearly reversible. The spring providing the closing of the door can accordingly be chosen to be less rigid, since the friction coefficient can be minimized. Thus, it takes up less space while requiring less energy from the actuator during the opening phase of the door. On the other hand, there is no reason to choose a helix angle that is too large, and it is therefore possible that a sufficiently low torque is required to turn the worm shaft, which also affects the output of the actuator.

The invention is described by way of example with reference to the accompanying drawings, in which:

FIG. 1 is a general side view of a swing door apparatus according to the present invention;

fig. 2 shows the door closer part comprised in the device of fig. 1 when the door is closed; and

fig. 3 shows the door closer part comprised in the device of fig. 1 when the door is opened.

In the drawings the reference numeral 1 designates a swinging door apparatus for a door (not shown) comprising an electric motor 7, or another suitable actuator, by means of which the opening of the door is accomplished, and a door closer 2 which closes the door. The door closer 2 comprises a piston means 3 driven by a drive shaft 4 connected to the door and rotating in accordance with the door movement, a return spring 5 and a worm shaft 6 driving the piston means 3 and providing the movement of the piston means 3 for opening the door. The operating shaft of the motor 7 is indicated by 8. A gear 8a is also provided between the motor and the working shaft 8, if necessary, in order to adapt the rotational speed of the shaft 8 to suit it. Furthermore, according to the invention, a coupling device 9 with a body part 10 is arranged between the shafts 6 and 8, which body part 10 is supported by the swing door apparatus.

The coupling device 9 can be realised in different ways and a preferred solution is disclosed in more detail in finnish patent application 20031180, to which reference is also made in this respect.

Figures 2 and 3 show a more detailed illustration of the structure of the door closer section in two different operating positions, i.e. when the door is closed and when it is opened, respectively. The drive shaft 4 is connected to the door (not shown in the figure) by means of an arm 13. On the drive shaft is mounted a toothed wheel 4a by means of which it is connected to the gear teeth 3a on the inner surface of the piston member 3. The piston member 3 is directly controlled by the inner surface of the door closer body part 2 a. The worm shaft 6 comprises a worm part 6a and a shaft part 6b connected thereto and provided with a flange 6c, which cooperates with a thrust bearing means 19. The worm portion 6a is coupled to a drive nut 11 which is in turn connected to the piston member 3. Rotation of the shaft 6, 6a, 6b thus moves the drive nut 11 and the piston member 3 in the direction of the shaft 6. One end of the drive nut 11 supports a guide 14 for the spring 5, which also guides a second spring 12. The springs 5 and 12 together act as a return spring and are supported at one end by a second guide 15.

The body part 2a preferably supports a complementary part 18, preferably threaded, which supports a thrust bearing support 16, the support 16 being secured in place by a locking ring 17. The thrust bearing support 16 comprises an axial projection 16a which, on the other hand, guides the inner spring 12 and by means of which the guide 15 is supported by a screw thread. Thus, the prestress of the springs 5 and 12 can be adjusted by turning the guide 15.

The situation in fig. 2 corresponds to the closed position of the door. Wherein the springs 5 and 12 of the door closer are not compressed except for the prestress provided to them by the guide 15. When the object is to open the door, the actuator 7 and its shaft 8 are connected to the shaft portion 6b of the worm shaft 6 by a coupling means 9 to provide drive. When the shaft 6 is rotated, the screw thread 6a of the screw portion acts on the drive nut 11 against the pressure of the springs 5 and 12 and causes the drive nut 11 and thus also the piston member 3 to move to the right in the figure.

The situation in fig. 3 corresponds to the open position of the door, thus compressing the springs 5 and 12. Therefore, the closing of the door can be simply accomplished by the normal operation of the door closer by using the pressure of the spring. In order to keep the energy consumption as low as possible, it is possible here to choose a smaller and less expensive spring for this purpose, the drive of the actuator 7 being decoupled from the shaft 6 by means of the coupling device 9. Furthermore, the angle of the helix of the worm part 6a and the drive nut 11 is chosen sufficiently large. In this way the movement of the piston member 3 and thus the closing of the door can be accomplished with as low a resistance as possible, while the movement of the shaft 6 in the axial direction is prevented by means of the flange portion 6c and the thrust bearing means 19.

The coupling device 9 may preferably be controlled by e.g. a solenoid 20. The operation of the clutch device according to the invention requires control logic and sensor means to indicate the position of the door at a given time and thus to control the operation of the solenoid guiding the coupling device. Thus, the swing door apparatus can reliably perform its automatic operation. In practice, the swing door apparatus is preferably controlled such that the drive from the motor 7 or the like to the drive shaft 4 is turned on only when the door is normally opened. Furthermore, in particular in certain special cases, for example when preventing the closing of a door, the drive can be switched on, thus requiring the door to be re-operated to its open position, or an auxiliary motor can be used if the pressure of the spring for closing the door is not high enough for only some reasons.

The invention is not limited to the above embodiments but several modifications are conceivable within the scope of the appended claims.

Claims (4)

1. An arrangement in a swinging door apparatus, comprising a door closer (2) provided with a return spring (5), which door closer comprises a body part (2a) and a piston member (3) movable inside thereof, which piston member is in force-transmitting connection with a drive shaft (4) which is turned in accordance with the door movement, and an actuator (7), the operating shaft (8) of which can be in operative connection with said piston member (3) for providing the door opening movement by means of a worm shaft (6) which is driven at one end by a drive nut (11) connected to the piston member (3) and which can be connected at the other end to said operating shaft (8) of the actuator, characterized in that: the worm shaft (6) comprises a worm part (6a) and a shaft part (6b) integral therewith and provided with a flange part (6c) which cooperates with thrust bearing means (19) and thus prevents movement of the worm shaft in the axial direction relative to the body part (2a) of the door closer, and coupling means (9) are provided between the working shaft (8) of the actuator and the shaft part (6b) of the worm shaft, which coupling means are arranged to disengage the force transmitting connection between the actuator (7) and the shaft part (6b) of the worm shaft and to provide said force transmitting connection to complete the opening movement of the door.

2. The apparatus of claim 1, wherein: one end of the drive nut (11) is connected to the piston member (3), and the other end is provided to engage with one end of a return spring (5) of the door closer.

3. The apparatus according to claim 1 or 2, characterized in that: the helix angle of the worm part (6a) of the worm shaft (6) and the drive nut (11) is chosen to be sufficiently large, at least 26 °, so that their reciprocal cooperation is reversible.

4. The apparatus according to claim 1 or 2, characterized in that: the helix angle of the worm section (6a) of the worm shaft (6) and the drive nut (11) is selected to be sufficiently large, 32 to 40, so that their reciprocal engagement is reversible.