GB2134174A - Hold open devices for hinged members - Google Patents

Abstract

The device consists of a length of spring steel strip (1) of shallow C-shape in transverse cross-section which is capable of acting as a strut when the hinged members (2, 3) to which it is attached are in an open condition, the strip being substantially straight in that condition. The ends (4, 5) of the strip are spaced from the hinge axis (C) and are integral with mounting portions (4', 5') secured to the members (2, 3). On closing of the hinged members by the application of sufficient force, the strip collapses into a curved shape. <IMAGE>

Description

SPECIFICATION Hold open devices for hinged members This invention relates to hold open devices for hinged members. The invention is primarily con- cerned with a hold open device for a vehicle door, but devices in accordance with the invention may be used on other hinged members such as trap doors and opening windows.

According to the invention a hold open device for two pivotally connected members comprises a strip of resilient material secured or adapted to be secured at its opposite ends to the respective members at positions spaced from the axis ofthe pivotal connection, the transverse cross-sectional shape ofthe strip having at least a portion of curved shape, and the arrangement being suchthatwhenthestrip has been fully extended by relative pivotal movement of the members to an open position it acts as a substantially rigid strut to resist closure of the members.

The device may be considered to utilise the characteristics of a steel tape measure of curved cross-section, which itwill be observed is capable of acting as a rigid member until it is flexed, whereupon the lengthwise forces that can be transmitted by the tape are limited.

The strip may be of spring steel, but a plastics laminate may be employed, possibly incorporating carbon fibres. The strip in its free state is preferably of shallow C-shape in cross-section, but other sections would be possible.

When the strip is of C-shape in cross-section it is preferably arranged with its concave side facing away from the pivotal axis.

The hold open device in accordance with the invention is conveniently combined with a hinge, opposite ends ofthe strip being secured to the respective leaves of the hinge.

The invention will now be further described, by way of example only, with reference to the accompanying drawings, in which: Figure lisa perspective view, partly broken away, of a hold open device in accordance with the invention; Figure 2 is a plan view of the hold open device shown in Figure 1; and Figure 3 is atransverse cross-section along line 111-111 of Figure 2.' A hold open device in the form of a spring steel strip 1 is shown in Figure 1 attached at one end to a door 2 and at the other end to a frame 3, the door being mounted on the frame by means of separate hinges (not shown).The end portions 4,5 of the strip 1 are clamped, screwed or otherwise fixedly attached, or could be pivotally connected, to the door 2 and the frame 3 respectively at positions spaced from the pivotal axis C of the door 2. Figure 2 shows the end portions 4,5 ofthe strip 1 to be integral with thickened mountings 4' and 5' respectively, to enable attachementto the door and frame, the mountings 4', 5' extending atthe appropriate angles away from the longitudinal axis of the strip for maintaining the door in the desired open position (as shown in unbroken lines in Figure 1).

In the fully open position, the strip is in a free and undistorted state, underwhich conditions it is able to act as a rigid strut. This abilityto bear end loads (up to a predetermined value) is conferred by the crosssectional configuration ofthe strip 1, which as shown is Figure 3 is a shallow C-shape. In closing the door, a force exceeding the said predeterminedvalue is exerted on the strip, causing itto collapse into a substantially C-shaped when viewed in the-directionh of the pivotal axis, as shown in dotted lines in' Figure2, to allow closure ofthe door2 and frame 3.The strip collapses preferentially in this direction upon closing the door as a result ofthe disposition of the C-shaped cross-section ofthe strip, with the convex face 6 ofthe strip facing the hinge axis and the concave face 7 ofthe strip facing away from the hinge axis, with the plane of cross-sectional symmetry of the strip disposed substantially horizontally as shown in Figure 3. A strip whose cross-sectional configuration does not confer this property could be guided into the required collapsed position by suitably positioned additional support surfaces (not shown) attached to or projecting from either or both of the door or frame and arranged to engage the strip during the closing operation.

1. A hold open device fortwo pivotally connected members comprising a strip of resilient material secured or adapted to be secured at its opposite ends to the respective members at positions spaced from the axis of the pivotal connection, thetransverse cross-sectional shape ofthe strip having at least a portion of curved shape, and the arrangement being such thatwhen the strip has been fully extended by relative pivotal movement of the members to an open position it acts as a substantially rigid strut to resist closureofthe members.

2. A hold open device as claimed in claim 1 in which the strip is of shallow C-shape in cross-section.

3. A hold open device as claimed in claim 2 in which the concave side of the strip faces away from the pivotal axis of the members.

4. A hold open device as claimed in any ofthe preceding claims in which the opposite ends of the strip are clamped in use to the respective members.

5. A hold open device as claimed in any of claims 1 to 3 in which the opposite ends of the strip are integral with mountings forthe strip.

6. A hold open device as claimed in any ofthe preceding claims in which the arrangement is sudh that the strip is bent into a substantially C shape, when viewed in the directioin of the pivotal axis, on closure ofthe hinged members.

7. A hold open devicefortwo pivotallyconnected members and substantially as described with reference to the accompanying drawings.

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

Claims (7)

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Hold open devices for hinged members This invention relates to hold open devices for hinged members. The invention is primarily con- cerned with a hold open device for a vehicle door, but devices in accordance with the invention may be used on other hinged members such as trap doors and opening windows. According to the invention a hold open device for two pivotally connected members comprises a strip of resilient material secured or adapted to be secured at its opposite ends to the respective members at positions spaced from the axis ofthe pivotal connection, the transverse cross-sectional shape ofthe strip having at least a portion of curved shape, and the arrangement being suchthatwhenthestrip has been fully extended by relative pivotal movement of the members to an open position it acts as a substantially rigid strut to resist closure of the members. The device may be considered to utilise the characteristics of a steel tape measure of curved cross-section, which itwill be observed is capable of acting as a rigid member until it is flexed, whereupon the lengthwise forces that can be transmitted by the tape are limited. The strip may be of spring steel, but a plastics laminate may be employed, possibly incorporating carbon fibres. The strip in its free state is preferably of shallow C-shape in cross-section, but other sections would be possible. When the strip is of C-shape in cross-section it is preferably arranged with its concave side facing away from the pivotal axis. The hold open device in accordance with the invention is conveniently combined with a hinge, opposite ends ofthe strip being secured to the respective leaves of the hinge. The invention will now be further described, by way of example only, with reference to the accompanying drawings, in which: Figure lisa perspective view, partly broken away, of a hold open device in accordance with the invention; Figure 2 is a plan view of the hold open device shown in Figure 1; and Figure 3 is atransverse cross-section along line 111-111 of Figure 2.' A hold open device in the form of a spring steel strip 1 is shown in Figure 1 attached at one end to a door 2 and at the other end to a frame 3, the door being mounted on the frame by means of separate hinges (not shown).The end portions 4,5 of the strip 1 are clamped, screwed or otherwise fixedly attached, or could be pivotally connected, to the door 2 and the frame 3 respectively at positions spaced from the pivotal axis C of the door 2. Figure 2 shows the end portions 4,5 ofthe strip 1 to be integral with thickened mountings 4' and 5' respectively, to enable attachementto the door and frame, the mountings 4', 5' extending atthe appropriate angles away from the longitudinal axis of the strip for maintaining the door in the desired open position (as shown in unbroken lines in Figure 1). In the fully open position, the strip is in a free and undistorted state, underwhich conditions it is able to act as a rigid strut. This abilityto bear end loads (up to a predetermined value) is conferred by the crosssectional configuration ofthe strip 1, which as shown is Figure 3 is a shallow C-shape. In closing the door, a force exceeding the said predeterminedvalue is exerted on the strip, causing itto collapse into a substantially C-shaped when viewed in the-directionh of the pivotal axis, as shown in dotted lines in' Figure2, to allow closure ofthe door2 and frame 3.The strip collapses preferentially in this direction upon closing the door as a result ofthe disposition of the C-shaped cross-section ofthe strip, with the convex face 6 ofthe strip facing the hinge axis and the concave face 7 ofthe strip facing away from the hinge axis, with the plane of cross-sectional symmetry of the strip disposed substantially horizontally as shown in Figure 3. A strip whose cross-sectional configuration does not confer this property could be guided into the required collapsed position by suitably positioned additional support surfaces (not shown) attached to or projecting from either or both of the door or frame and arranged to engage the strip during the closing operation. CLAIMS

1. A hold open device fortwo pivotally connected members comprising a strip of resilient material secured or adapted to be secured at its opposite ends to the respective members at positions spaced from the axis of the pivotal connection, thetransverse cross-sectional shape ofthe strip having at least a portion of curved shape, and the arrangement being such thatwhen the strip has been fully extended by relative pivotal movement of the members to an open position it acts as a substantially rigid strut to resist closureofthe members.

2. A hold open device as claimed in claim 1 in which the strip is of shallow C-shape in cross-section.

3. A hold open device as claimed in claim 2 in which the concave side of the strip faces away from the pivotal axis of the members.

4. A hold open device as claimed in any ofthe preceding claims in which the opposite ends of the strip are clamped in use to the respective members.

5. A hold open device as claimed in any of claims 1 to 3 in which the opposite ends of the strip are integral with mountings forthe strip.

6. A hold open device as claimed in any ofthe preceding claims in which the arrangement is sudh that the strip is bent into a substantially C shape, when viewed in the directioin of the pivotal axis, on closure ofthe hinged members.

7. A hold open devicefortwo pivotallyconnected members and substantially as described with reference to the accompanying drawings.