ZA200709828B - A door stopper - Google Patents

Description

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THIS INVENTION relates to a door stopper. It relates, more particularly, to an impact absorbing door stopper for countering slamming of a door.

It is known that slamming of a door, typically a cupboard door, or the like, can be the cause of irritation and also can result in damage to the door. It is thus an object of this invention to at least ameliorate these problems.

According to the invention there is provided a door stopper, which includes a body that can be mounted in a predetermined operative configuration against an object and that defines opposite first and second ends and a passage defined by a peripherally surrounding slide surface and extending from a blind end at the first end of the body towards the second end of the body; a plunger defining a peripheral outer surface mated to the slide surface defining the passage defined in the body and located in a snug sliding fit mode within the passage, to define an air chamber within the passage between the plunger and the blind end of the passage, the plunger being displaceable within the passage between first and second positions, of which the second position is intermediate the first position and the first end of the body and the plunger having a contact formation that extends therefrom and that projects from the second end of the body, with maximum projection occurring with the plunger in its first position; and a 72007709828 biasing means biasing the plunger towards its first position, : and in which an air flow passage is defined which, in response to forces acting on the plunger for displacing it within the passage, permits restricted air flow only into and from the air chamber defined within the passage between the plunger and the blind end of the passage, to thereby control the rate of displacement of the plunger.

The operation of the door stopper of the invention is explained hereafter with reference to a door that pivots on a hinge, although it must be appreciated that it can serve similarly to counter slamming of a sliding door, which will be clearly apparent.

For use with a door that pivots on a hinge, the door stopper of the invention is operatively mounted on a fixed object, e.g. a door frame, a wall, or a structural element of a cupboard, at the side of the door opening opposite to the hinge and in an orientation in which the direction of displacement of the plunger is generally tangential to a circle co-axial with the axis of the hinge of the door. The location of the body of the door stopper when mounted on a fixed object particularly is such that, during closing of the associated door and prior to the door being completely shut, the door will contact the free end of the contact formation while disposed in its first position, so that further displacement of the door, bearing on the contact formation, into its completely shut position, will urge the plunger towards its second position, with the body of the door stopper still clearing the door. If such closing of the door occurs rapidly, the door impacts the contact formation of the plunger and urges it towards its second position, in which case the air in the air chamber defined within the passage between the plunger and the first end of the body is pressurized due to the fact that the air flow passage defined by the stopper permits only restricted air flow out of the chamber. This air pressure will counter the impact of the door acting on the plunger and the effect is controlled deceleration of the door before slamming shut. The door stopper thus serves as a damper or impact absorber, preventing the door from slamming shut, or at least reducing the impact of slamming.

The displacement of the plunger from its first to its second position clearly occurs against the bias of the biasing means. However, the biasing force of the biasing means is not sufficient to displace the door, when in its shut position and thus in contact with the plunger via the contact formation, from this position. The biasing means thus merely serves, upon opening of the door, to displace the plunger into its first position, thus rendering the door stopper ready to absorb the next impact of the door closing.

According to a preferred embodiment of the door stopper of the invention, the passage defined by the body and the plunger define circular cross-sectional profiles, although other profiles also are envisaged.

The contact formation of the plunger may be a shaft that extends from the plunger and that defines a nose portion at its free end, the nose portion being formed of an impact absorbing material.

Furthermore, the body may include a closure that closes the passage at the second end defined by the body, the closure defining a passage therethrough through which the contact formation extends to project from the second end of the body.

The air flow passage that is defined may be defined between the slide surface defining the passage in the body and the outer surface of the plunger, although it is envisaged also that this air flow passage can be alternatively configured or defined in order to serve the purpose defined.

The biasing means of the door stopper may be a coil spring that is located within the air chamber acting between the plunger and the body at the first end of the body.

Further according to the invention, the plunger may include an impact absorbing stop formation that projects therefrom within the air chamber towards the first end of the body in a configuration in which it will abut against the inside of the first end of the body upon displacement of the plunger from its first position beyond its second position, the impact absorbing stop formation including a shaft that extends from the plunger and that terminates in a nose portion of an impact absorbing material.

The door stopper of the invention includes mounting means for mounting the body in its predetermined operative configuration against an object. The mounting means may include apertured lug formations that extend integrally from the body to permit the body to be mounted in its predetermined operative configuration against an object with the aid of securing screws, or the like.

The invention is described below by way of an example of an embodiment of a door stopper, in accordance with the invention, with reference to and as illustrated in the accompanying diagrammatic drawings. In the drawings:

Figure 1 shows a partial plan view of a cupboard, including a door frame, a door, and a hinge, and an embodiment of a door stopper, in accordance with the invention, mounted in an operative configuration on the cupboard;

Figure 2 shows a section through the door stopper of Figure 1, along the line II-ll of Figure 1 and in the direction of the associated arrows, with a plunger thereof in a first position thereof; and

Figure 3 shows a section corresponding to that shown in Figure 2, but with the plunger in a second position thereof.

In Figure 1, a cupboard has two structural elements 10.1 and 10.2 forming part of a frame of a door 12 of the cupboard. The door 12 is mounted on the frame 10.2 via a vertically disposed piano-type hinge 14.

An embodiment of a door stopper, in accordance with the invention, designated by the reference numeral 16, has been mounted on the structural element 10.1 in the configuration shown.

With reference particularly to Figure 2, the door stopper 16 includes a body 18 defining a first end 19.1 and a second end 19.2. The body 18 may be made of any suitable material, e.g. an injection moulded plastics, a metal, or a metal alloy. The body 18 includes a cylindrical outer wall 20 defining therein a cylindrical slide passage 22. At the end 19.1 of the body 18, it includes an end wall 24, defining a blind end of the passage 22. The body 18 includes also four apertured lug formations 26 via which the body is secured to the structural element 10.1 via four screws 28. At its end 19.2, the body 18 includes a clip-in closure in the form of a cap 30, engaged with and closing off this end.

The door stopper 16 includes also a plunger 32 that has a contact formation in the form of a shaft 36 extending therefrom, the shaft projecting through a central passage 38 defined through the cap 30 in a snug sliding fit. The shaft 36, at its end remote from the plunger 32, terminates in a contact nose 40, made of impact absorbing rubber.

The plunger 32 also has an opposite shorter shaft 42 extending therefrom, the shaft 42 also terminating in a contact nose 44 identical or similar to the nose 40. Biasing means in the form of a weak coil spring 46 in the passage 22 acts between the wall 24 and the plunger 32. The purpose of this spring will be described later on herein.

The body 18 defines a cylindrical inner slide surface 48 around the passage 22 and the plunger 32 defines a peripheral surface 49, herein referred to as the mated surface, which is mated to the surface 48, providing a snug sliding fit of the piston within the passage 22, albeit with some clearance provided between the surfaces 49 and 48 to define a restricted airflow passage past the plunger 32. Two air filled chambers 50 and 52 are defined within the passage 22 on opposite sides of the piston 34 and the said flow passage is thus defined between the two chambers.

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In Figure 2, the plunger 32 is shown in a first position thereof, into which it is biased by the spring 46. By applying an impact force (see arrow 53 in Figure 3) on the nose 40 in the direction towards the wall 24, the plunger 32 is biased into a second position thereof, as shown in Figure 3, against the bias of the spring 46. If such a force of high impact is applied, displacement of the plunger 32 will be resisted due to compression of air in the chamber 50. This air can only escape from this chamber 50 via the restricted airflow passage defined past the plunger 32 and into the chamber 52. As such, the stopper 16 resists the impact and has a damping effect. Upon the force being removed, the spring 46 merely displaces the plunger back into its first position, with reverse air flow via the flow passage occurring from the chamber 52 to the chamber 50.

Should the impact on the nose 40 exceed the capacity of the door stopper 16, the nose 44 will strike the wall 24 before the nose 40 reaches the cap 30, thus absorbing at least some of the impact.

With reference again particularly to Figure 1, the door stopper 16 clearly is mounted horizontally on the element 10.1 with the shaft 36 of its plunger projecting past the plane defined by a front face 56 of the element 10.1. The body 18, however, is on the opposite side of the plane.

Clearly, upon rapid closure of the door 12, an impact area on the inner surface 58 of the door will contact the nose 40 (see Figure 2) of the shaft 36 and exert an impact on it, urging the shaft into the body 18. The stopper 16 opposes this impact and decelerates the door 12 over the distance through which the shaft 36 travels. Slamming impact of the door 12 against the surface 56 is thus prevented or ameliorated.

It will be apparent to those skilled in the art of the invention that, instead of a flow passage being defined past the plunger 32, in another embodiment of the door stopper of the invention (not shown), such a passage may be defined in another configuration, for example through the piston 32 or through the wall 24.

Different embodiments of the door stopper of the invention, having different impact absorption capacities, are envisaged for different types of doors.

Moreover, the configuration of the door stopper of the invention is variable and, as such, the invention extends to any door stopper including the essential features of the door stopper of the invention, as defined herein.

Claims (11)

CLAIMS I | | [ | | | I at

1. A door stopper, which includes a body that can be mounted in a predetermined operative configuration against an object and that defines opposite first and second ends and a passage defined by a peripherally surrounding slide surface and extending from a blind end at the first end of the body towards the second of the body; a plunger defining a peripheral outer surface mated to the slide surface defining the passage defined in the body and located in a snug sliding fit mode within the passage, to define an air chamber within the passage between the plunger and the blind end of the passage, the plunger being displaceable within the passage between first and second positions of which the second position is intermediate the first position and the first end of the body and the plunger having a contact formation that extends therefrom and that projects from the second end of the body, with maximum projection occurring with the plunger in its first position; and biasing means biasing the plunger towards its first position, and in which an air flow passage is defined which, in response to forces acting on the plunger for displacing it within the passage, permits restricted air flow only into and from the air chamber defined within the passage between the plunger and the blind end of the passage, to thereby control the rate of displacement of the plunger.

2. A door stopper as claimed in Claim 1, in which the passage defined by the body and the plunger define circular cross-sectional profiles.

3. A door stopper as claimed in Claim 1 or Claim 2, in which the contact formation of the plunger is a shaft that extends from the plunger and that defines a nose portion at its free end.

4. A door stopper as claimed in Claim 3, in which the nose portion of the shaft is formed of an impact absorbing material.

5. A door stopper as claimed in any one of the preceding claims, in which the body includes a closure that closes the passage at the second end defined by the body, the closure defining a passage therethrough through which the contact formation extends to project from the second end of the body.

6. A door stopper as claimed in any one of the preceding claims, in which the airflow passage is defined between the slide surface defining the passage in the body and the outer surface of the plunger.

7. A door stopper as claimed in any one of the preceding claims, in which the biasing means is a coil spring that is located within the air chamber, acting between the plunger and the body at the first end of the body.

8. A door stopper as claimed in any one of the preceding claims, in which the plunger includes an impact absorbing stop formation that projects therefrom within the air chamber towards the first end of the body in a configuration in which it will abut against the inside of the first end of the body upon displacement of the plunger from its first position beyond its second position, the impact absorbing stop formation including a shaft that extends from the plunger and that terminates in a nose portion of an impact absorbing material.

9. A door stopper as claimed in any one of the preceding claims, which includes mounting means for mounting the body in its predetermined operative configuration against an object.

10. A door stopper as claimed in Claim 9, in which the mounting means includes apertured lug formations that extend integrally from the body to permit the body to be mounted in a predetermined operative configuration against an object with the - aid of securing screws.

11. A door stopper as claimed in Claim 1, substantially as herein described, with reference to and as illustrated in the accompanying drawings. DATED THIS 13™ DAY OF NOVEMBER 2007 ADAMS & ADAMS APPLICANTS PATENT ATTORNEYS