GB2335230A

GB2335230A - Slotted friction stay

Info

Publication number: GB2335230A
Application number: GB9804718A
Authority: GB
Inventors: Clive James Smith
Original assignee: Euromond Ltd; Cego Frameware Ltd
Current assignee: Euromond Ltd; Era Security Hardware Ltd
Priority date: 1998-03-05
Filing date: 1998-03-05
Publication date: 1999-09-15
Also published as: GB9804718D0

Abstract

A friction stay comprises a base 10 and an arm 11 connected to the base by a linkage. The linkage includes a shorter link 12 and a longer link 13 and one of the links is connected to the base member by a rivet 48 which forms a pivotal connection and also extends through a slot 27 in the base member. The connection also includes a spacer (57, fig. 3) and a friction member (54) with parallel ribs (56) contacting the base member. This allows the end of the shorter link to slide along the slot as the arm is moved between a closed position in which it overlies the base member and an open position in which it is to one side of the base member and angled relative to the base member.

Description

2335230 1 FRICTION STAYS The invention relates to friction stays.

A friction stay is used to mount a leaf in a frame for opening and closing movement into and out of the frame. An example of a leaf/frame combination is a window leaf and a window frame.

A friction stay comprises an elongate base member for connection to the frame and an arm for connection to the leaf. The arm is connected to the base by a linkage that constrains the arm to movement in a plane parallel to the base member between a closed position in which the arm overlies the base member and an open position in which the arm is to one side of the base member and is angled relative to the base member.

In a known friction stay, the linkage includes a longer link and a shorter link with each link having a f irst end and a second end and being pivotally connected at the first end of the arm and pivotally connected at the second end to the base member. At least one of the pivotal connections at the base member is to a slider which is held by the base member for sliding movement back and forth along the base member. This 2 allows sliding movement of the second end of the associated link during opening and closing movement of the arm.

is According to the invention, there is provided a friction stay comprising an elongate base member and an arm connected to the base member by a linkage that constrains the arm to movement in a plane parallel to the base member between a closed position in which the arm overlies the base member and an open position in which the arm is to one side of the base member and is angled relative to the base member, the linkage including a longer link and a shorter link, each link having a first end and a second end and being pivotally connected at the first end to the arm and pivotally connected at the second end to the base member, one of said second end pivotal connections -ncluding a fastener extending through the associated link and through a slot in the base member, the fastener being guided by the slot to permit sliding movement of the second end of the associated link as the arm moves between the open and closed positions.

The following is a more detailed description of an embodiment of the invention, by way of example, reference being made to the accompanying drawings in which:- j 1 3 Figure 1 is a plan view from above of a friction stay showing an arm of the friction stay in an open position to one side of a base member of the stay, Figure 2 is a side elevation of the friction stay of Figure 1 showing the arm overlying the base member, and Figure 3 is a section on the line A-A of Figure Referring first to Figure 1, the friction stay comprises a base member 10, an arm 11 and a linkage connecting the arm 11 to the base member 10. The linkage includes a shorter link 12, a longer link 13 and an intermediate link 14. The base member 10, the arm 11 and the links 12,13,14 are preferably is made from metal strip.

The base member 10 has generally parallel side edges 15, a first end provided with a shaped guide portion 16 anda rounded second end 17. The shaped guide portion 16 is formed by contiguous first and second planar surfaces 18,19. The plane of each surface 18,19 is normal to the plane of the remainder of the base member 10 and each plane makes an acute angle with the length 20 of the base member 10. The second 4 planar surface 19 makes a larger acute angle with this length than the first planar surface 18, as seen in Figure 1.

is The base member 10 also has an upper side indicated generally at 21 in Figure 2 and a lower side indicated generally at 22 in Figure 2. The lower side 22 includes two planar end surfaces 23 adjacent the first and second ends 16,17 of the base member respectively and an intermediate surface 24 between the end surfaces 23. The end surfaces 23 are coplanar and the intermediate surface 24 lies in a plane parallel to the plane of the end surfaces 23 and is recessed relative to the end surfaces 23.

At one end, the intermediate surface 24 is contiguous with one of the end surfaces 23 and at the other end, the intermediate surface 24 leads to a central surface 25 co-planar with the end surfaces 23 which in turn leads to a second recessed intermediate surface 26 that is connected to the other of the end surfaces 23. The first mentioned intermediate surface 24 and the second intermediate surface 26 are co-planar.

The end surface 23 adjacent the rounded end 17 is provided with two fixing holes 28.

i The upper side 21 of the base member 10 is provided with parallel corresponding end surfaces, intermediate surfaces and central surface. This again is seen in Figure 2.

A slot 27 extends through the intermediate surface 24 and has its length aligned with the length 20 of the base member 10. This is best seen in Figure 1.

is The arm 11 has parallel side edges 29. The width of the arm 11 is substantially the same as the width of the base member 10. The arm has a first end indicated generally at 30 and a rounded second end indicated generally at 31. The second end is provided with a fixing hole 32. The portion of the arm 11 adjacent the first end 30 is stepped relative to the remainder of the arm so that the first end 30 lies in a plane parallel but spaced to the plane of the remainder of the arm 11. This is seen in Figure 2. The end surface of the first end 30 is formed by a straight edge 33 that intersects the length 34 of the arm 11 at an acute angle, as seen in Figure 1.

The shorter arm 12 has parallel side edges 35 and is generally of the same width as the base member 10 and the arm 11. The 6 shorter link has a first rounded end 36 and a second rounded end 37. The shorter link is planar.

The longer link 13 has parallel side edges 38 and is generally of the same width as the shorter link 12. The longer link 13 has a first end portion 39, a second end portion 40 and an intermediate portion 41. The intermediate portion 41 is recessed relative to the first end portion 39 and the second end portion 40 is recessed relative to the intermediate portion 41. This is seen in Figure 2.

The intermediate link 14 has parallel side edges 42 and is generally the same width as the longer link 13. The intermediate link 14 has a rounded first end 43 and a rounded second end 44.

The first end portion 36 of the shorter link 12 is connected to the arm 11 by fastening means in the form of a rivet 45 which forms a pivotal connection between the shorter link 12 and the arm 11 about an axis normal to the plane of the arm 11. The connection of the second end 37 of the shorter link 12 to the base member 10 will be described below.

1 7 The first end portion 39 of the longer link 13 is connected to the second end portion 31 of the arm 11 by a rivet 46 which forms a pivotal connection between the longer link 13 and the arm 11 about an axis normal to the plane of the arm 11. The second end portion 40 of the longer link 13 is connected to the second intermediate portion 26 of the base member 10 by a rivet 47 which forms a pivotal connection about an axis normal to the plane of the base member 10. The first end 43 of the intermediate link 14 is connected to the intermediate portion 41 of the longer link 13 by a rivet 48 which forms a pivotal connection about an axis normal to the plane of the intermediate link 14.

The connection between the second end 37 of the arm 11 and the base member 10 and between the second end 44 of the intermediate link 14 and the base member 10 will now be described with particular reference to Figure 3. Figure 3 shows a section through the connection between the intermediate link 14 and the base member 10, but it will be appreciated that the connection between the shorter link 12 and the base member 10 is similar. Accordingly, this latter connection will not be described in detail.

8 Referring to Figure 3, a fastener in the form of a rivet 49 has a head 50 and a splayed end 51. The splayed end 51 engages around the periphery of an aperture 52 provided in the second end 44 of the intermediate link 14. The head 50 of the rivet 49 engages in a recess 53 provided in a plastics friction member 54. The friction member 54 has a body 55 and a pair of spaced parallel ribs 56. As seen in Figure 3, the rivet 49 clamps the friction body 54 so that the ribs 56 are forced against the intermediate surfaces 24 of the lower side 22 of the base member 10. In this disposition, the ribs 56 extend parallel to the slot 27 and are spaced on either side of the slot 27.

A plastics disc-shaped spacer 57 is clamped by the rivet 49 between the second end 44 of the intermediate link 14 and the upper side 21 of the base member 10. The spacer includes a central hole 60 through which the rivet 49 passes and a tube 59 which is formed as a continuation of the hole. The tube 59 has a diameter equal to the width of the slot 27 so that, as seen in Figure 3, the outer surface of the tube 59 engages the edges of the slot 27.

is 9 AS mentioned above, the connection between the shorter link 12 and the base member 10 is similar. There is, however, only one friction member 54; the length of the friction member 54 being such as to extend to the rivet which extends through the second end 37 of the shorter link 12.

In operation, the arm 11 can be swung from the open position shown in Figure 1 in which the arm 11 is to one side of the base member 10 and angled relative to the base member 10 to the closed position shown in Figure 2 in which the arm 11 overlies the base member 10. This swinging movement is in a plane parallel to the plane of the base member 10.

As the arm 11 moves from the open position of Figure 1 to the closed position of Figure 2, the longer link 13 applies to the shorter link 12 and the intermediate link 14 a force tending to push the rivets 49 connecting these links to the base member 10 towards the shaped portion 16 of the base member 10. The clamping force of the rivets 49 is chosen so that the ribs 56 of the friction member 54 provide a frictional resistance to such movement which is sufficient to hold the arm 11 in any desired position relative to the base member 10 in the absence of opening or closing forces. The application of opening or closing forces is, however, sufficient to overcome these frictional forces and allow movement of the arm 11.

These forces on the rivets 49 slide the spacers 57 along the slot 27 and also slide the friction member 54 along the intermediate surface 27 on the lower side 22 of the base member 10. The extent to which the intermediate surface 24 is recessed from the end surface 23 is such that the friction member 54 does not project beyond the plane of the end surfaces 23.

As the arm 11 approaches the closed position, the edge 33 on the arm 11 engages the first planar surface 18 of the shaped portion 16 and this prevents the first end 30 of the arm 11 going over-centre. When the arm 11 is very close to the closed position, the edge engages the second planar surface 19 to guide the arm 11 to its final closed position.

During this movement, the second end 37 of the shorter link 12 and the second end 44 of the intermediate link 14 slide together along the slot as a result of the interconnection by the friction member 54. On reverse movement of the arm 11 i 1 11 from the closed position to the open position, reverse sliding movement is performed.

In use, a pair of such friction stays of the kind described above with reference to the drawings, are connected between a leaf and a frame. This may be a door leaf and a door frame or a window leaf and a window frame. The arm 11 is connected to the leaf and the base member 10 is connected to the f rame. This mounts the leaf for movement between a closed position in which the leaf is received in the frame when the arm 11 overlies the base member 10 and an open position in which the leaf is out of the frame to one side of the frame and is angled relative to the frame with the arm 11 and the base member 10 in relative positions similar to that shown in Figure 1. The base member 10 and the arm 11 are connected to the frame and the leaf respectively by screws passing through the fixing holes 28,32.

In the fully open position (when the arm 11 makes an angle of about 801 with the base member 10) the arm 11 is aligned with the shorter link 12. The shorter link 12 thus provides good support for the arm 11 in this position since the end of the arm 11 overlies and is supported by the shorter link 12.

is 12 The friction stay described above with reference to the drawings has a number of advantages. As compared with some known friction stays, it omits the requirement for a channel and a slider. This reduces the cost of this component and also reduces the height of the base member. The friction stay can be made of small size that has high strength since the parts support each other on opening. No adjustment of the friction is required; the rivets 49 providing set friction. No special end cap is required; the end cap function being performed by the shaped end portion 16 and the edge 33.

It will be appreciated that there are a number of alterations that can be made to the friction stay described above. The rivet/friction member/spacer arrangement can be applied to the second end portion 40 of the longer link 13. The intermediate link 14 could be omitted. In this case, the shorter link 12 could be connected to the base member 10 by a fixed pivot.

A fastener other than a rivet could be used. The friction member 54 need not have a body and ribs; it could be performed by any surface which provides the required frictional forces. Separate spacers 57 need not be provided; a single spacer could accommodate both the rivet 49 at the end of the intermediate link 14 and the rivet 49 at the end of the shorter link 12.

1 13

Claims

CLAIMS is 1. A friction stay conprising an elongate base member and an arm

connected to the base member by a linkage that constrains the arm to movement in a plane parallel to the base member between a closed position in which the arm overlies the base member and an open position in which the arm is to one side of the base member and is angled relative to the base member, the linkage including a longer link and a shorter link, each link having a first end and a second end and being pivotally connected at the first end to the arm and pivotally connected at the second end to the base member, one of said second end pivotal connections including a fastener extending through the associated link and through a slot in the base member, the fastener- being guided by the slot to permit sliding movement of the second end of the associated link as the arm moves between the open and closed positions.

2. A friction stay according to claim 1 wherein means are associated with the fastener for providing frictional resistance to said sliding movement.

14 3. A friction stay according to claim 2 wherein the fastener holds a friction member against a surface of the base member, the friction member providing said frictional resistance.

is 4. A friction stay according to claim 3 wherein said base member has an upper side and a lower side, the slot extending between said upper and lower sides, the arm and the links overlying the upper side of the base member in the closed position, the friction member engaging the lower side of the base member and being urged against said lower side by the fastener.

5. A friction stay according to claim 4 wherein the friction member includes a body engaging the fastener and at least one rib urged against the lower side of the base member.

6. A friction stay according to claim 5 wherein the friction member includes two spaced ribs.

7. A friction stay according to claim 5 or claim 6 wherein the or each rib extends in a direction parallel to the length of the base member.

is 8. A friction stay according to any one of claims 4 to 7 wherein the friction member is of a plastics material.

is 9. A friction stay according to any one of claims 4 to 7 wherein the lower side of the base member includes two end surfaces and an intermediate surface between the end surfaces, the end surface being coplanar and the intermediate surface being in a plane parallel to the plane of the end surfaces and being recessed relative to said end surfaces so that the friction member does not project beyond the plane of the end surfaces.

10. A friction stay according to any one of claims 4 to 8 wherein a spacer is located between the second end of the link having the fastener and the base member, the spacer having a sliding surface engaging the base member.

A friction stay according to claim 10 wherein the spacer includes a central hole through which the fastener passes, a tube extending from the spacer as a continuation of the hole and extending through the slot, an exterior surface of the tube engaging side edges of the slot to guide the sliding movement of the associated link.

16 12. A friction stay according to claim 10 or claim wherein the spacer is of a plastics material.

13. A friction stay according to any one of claims 1 to 11 wherein the fastener is a rivet.

14. A friction stay according to any one of claims 1 to 13 wherein the shorter link is the link permitted sliding movement.

is. A friction stay according to claim 14 wherein an intermediate link is provided and has first and second ends, the first end being pivotally connected to the longer link and the second end being pivotally connected to the base member, the second end pivotal connection including a fastener extending through the intermediate link and through the slot in the base member, the fastener being guided by the slot to permit sliding movement of the second end of the intermediate link as the arm moves between the open and closed positions.

16. A friction stay according to any one of claims 1 to 15 wherein the arm has a first end and a second end, the pivotal connection between the first end of the shorter link and the i 1 17 arm being towards the first end of the arm, the first end of the arm being formed with a shaped portion that engages a shaped portion on the base member as the arm moves to the closed position to align the arm with the base member in the closed position.

17. A friction stay according to claim 16 wherein the shaped portion of the arm comprises an end surface of the arm intersecting the length of the arm at an acute angle.

18. A friction stay according to claim 17 wherein the shaped portion of the base member comprises a surface lying in a plane normal to the plane of the base member and intersecting the length of the base member at an acute angle.

19. A friction stay according to claim 18 wherein the shaped portion of the base member includes a second surface lying in a plane normal to the plane of the base member and intersecting the length of the base member at an acute angle greater than the angle of intersection of the first-mentioned surface, the firstmentioned surface and the second surface being contiguous.

18 20. A friction stay substantially as hereinbefore described with reference to the accompanying drawings.