SAFETY DEVICE FOR LADDERS

Abstract: The device is a substantially rectangular frame (10, 11, 12, 13) which can loosely girdle a ladder (20) for sliding movement along the ladder and across the ladder from front to back. The frame has a U-shaped abutment (15) in one longer side (12), this abutment (15) lies at the front side of the ladder and extends towards the ladder. When the device is moved reawards so that side (12) abuts the front of the ladder, the abutment (15) extends between the ladder stiles (21) into the longitudinal plane of the rungs (22). The device has a spring clip (14) in its rear side (13) and can be attached to a person's belt or harness. In use the person can move up and down the ladder with the safety device hanging forwards (A) so that the abutment does not engage the rungs. If the person slips his movement will draw the device rearwards and bring the abutment into the space between two rungs (B). A short downward movement of the device will then bring the abutment to overlie the lower rung (C) and arrest any further downward movement of the device and of the person attached to it.

Description: - 1 - SAFETY DEVICE FOR LADDERS. BACKGROUND OF THE INVENTION. This invention relates to a safety device for use on ladders. A disadvantage when working on ladders, especially extending ladders where a substantial height is to be climbed, is securing the user against a fall. It is known to provide a harness or some other form of support at the upper end of the ladder, but in such cases, the user is unprotected while climbing to and from said support. It is an object of the invention to provide means for supporting a user no matter where on the ladder he is located. SUMMARY OF THE INVENTION. According to one aspect of the present invention there is provided a device for supporting a person on a ladder comprising a frame adapted to extend around said ladder with sufficient clearance to move relative to said ladder, at least a portion of said frame extending at an angle relative to the remaining frame portion, said angularly extending portion extending inwardly towards said ladder and having a length less than the distance between the stiles of said ladder, and means on said frame at a position opposite that of said angularly-extending portion for connecting to a belt, or the like, on said person, so that movement of said person downwardly on said ladder causes said angularly-extending portion to move between said stiles and engage a rung on said ladder to prevent further downward movement. According to another aspect of the present inventio there is provided a safety device for use on ladders, comprising a frame adapted to girdle a ladder for sliding movement along the ladder and across the ladder in the front and rear directions and having an abutment for a on on one side of the ladder and which can locate across the longitudinal plane of the rungs to engage over a rung and prevent downward movement of the device when the device is moved against said side of the ladder. Preferably, the angular abutment forms part of a side member which when the device is mounted on a ladder extends across the front face of the ladder parallel to the rungs, a second side member being located across the opposite face of the ladder, the device also including end members spacing the side members apart and of a length greater than the depth of the ladder stiles to permit movement of the abutment towards or away from the plane of the rungs so that, in the latter position the device can move along the ladder. Preferably, the frame of the safety device is substantially rectangular and planar but with the abutment angled relative to the remainder of the frame at an angle of e.g. 20 to the plane. Preferably also, the other side member mounts centrally a spring clasp for attachment of a belt or harness thereto. BRIEF DESCRIPTION OF THE DRAWINGS. An embodiment of the present invention will now be described, by way of example with reference to the accompanying drawings, in which: Fig. 1 is a perspective view of a safety device according to the invention; Fig. 2 is an end view; Fig. 3 is a plan view showing the device girdling a ladder; and Figs. 4 and 5 are side and perspective views respectively illustrating three positions of the device when in u.se on a ladder. DESCRIPTION OF THE PREFERRED EMBODIMENT. - Referring firstly to Figs. 1 and 2, the device comprises a substantially rectangular metal frame having two ends 10, 11 and two sides, 12, 13. One side 13 has a loop 13A which carries a spring clasp 14 for 5 connection to a belt or harness worn by a person using the ladder. The other side 12 has a central portion 15 of a substantially U-shaped configuration which extends a short distance into the area of the rectangle and at an angle to the plane of the rectangle of 10 approximately 20° as best shown in Fig. 2. The device is shown mounted on a ladder 20 Fig. 3 so as to girdle it for sliding movement up and down the ladder. The ends 10, 11 are longer than the depth of the ladder rung supports, or stiles21 so that the 15 device is loosely mounted for movement transverse of the rungs -22, i.e ; to and away from a person and can be angularly adjusted. Referring now to Figs. 4 and 5 in which a safety device is shown in three different angular positions; 20 position A illustrates the normal angular disposition of the device wherein the device can freely slide up or down the ladder. In this position, the abutment side 12 of the frame lies horizontally below the other side 13 and the angled abutment portion 15 as disposed 25 substantially upright, while the upper side 13 tends to rest upon the stiles of the ladder. As a result the abutment 15 is outside the plane of the rungs and does not impede movement of the device. In position B, the device is disposed substantial- 30 ly horizontal and the angularly extending abutment 15, is drawn towards the rungs 22 so as to lie in the plane, of the rungs. Thus, downward movement of the device in this disposition will result in the abutment 15 engaging the next lower rung. Position C indicates 35 such an abutment which causes the other side 13 to move horizontally below the level of the abutment. A person using the device will place it around the ladder 20 from the bottom and draw it upwards as shown at A in Fig. 5. The clasp 14 is then connected to the users belt or harness. The user can then climb and descend the ladder with the device in the position A. I-f the person loses balance or footing and begins to slide or fall, the device will move into position B and quickly thereafter into position C to hold the person against further downward movement. Provided the ladder 20 is secured or stabilized, a person harnessed to the device as hereinbefore described should be secured against falling. The ladder may be secured, e.g. by ropes or hooks at its upper end, or stabilized by a ladder attachment such as described and claimed in my co-pending Application No. PCT/GB 81 00146 filed 28 July 1981. The space between the abutment 15 and the ends 10, 11 is greater than the width of the ladder stiles 21 so that a slight lateral movement of the device is possible. Thus the user can reach sideways of the ladder a short distance beyond his normal reach; thereafter the device will prevent further, excessive sideways movement. The device may be manufacturered from a metal rod bent to the required shape and welded at the abutting ends. While the device is primarily intended as a safety device for a person moving up or down a ladder, it can also be used by the person as an anchoring device when the person is working at a particular position on the ladder; in this mode the user simply tilts the device so that the abutment 15 hooks over the nearest convenient rung. _ A person using the device need not hold on to the ladder and so can use his hands for other purposes such as carrying tools or equipment.

Claims: CLAIMS 1. A device for supporting a person on a ladder characterised by a frame (10-13) adapted to extend around said ladder with sufficient clearance to move relative to said ladder at least a portion (15) of said frame extending at an angle relative to the remaining frame portion, said angularly-extending portion (15) extending inwardly towards said ladder and having a length less than the distance between the stiles (21) of said ladder, and means (14) on said frame at a position opposite that of said angularly-exrending portion for connecting to a belt, or the like, on said person, so that movement of said person downwardly on said ladder causes said angularly- extending portion to move between said stiles (21) and engage a rung (22) on said ladder to prevent further downward movement. 2. The device of claim 1 characterised in that said frame (10-13) comprises two end members (10,11) and two side members (12,13) connected together in a substantial rectangular configuration, with said side members (12,13) extending parallel to the rungs (22) of the ladder. 3. The device of claim 2 characterised in that said angularly-extending portion (15) is formed by a portion of one of said side members (12) . 4. The device of claim 3 characterised in that said angularly-extending portion (15) is formed by a portion of said one side member (12) bent into a substantially U-shaped configuration. 5 " . The device of claim 3 characterised in that said connecting means (14) is formed on the side member (13) of said frame opposite said one side member (12) . 6. The device of claim 2 characterised in that the length of the rectangle formed by said end members (10,11) and said side metiers (12,13) is slightly greater than the width of said ladder and the width of said rectangle is GM?I greater than the depth of said ladder. 7.. The device of claim 1 characterised in that said angle is approximately 20 . 8. A safety device for use on ladders characterised by a frame (10-13) adapted to girdle a ladder for sliding movement along the ladder and across the ladder in the front and rear directions and having an abutment (15) for location on one side (12) of the ladder and adapted to locate across the longitudinal plane of the rungs (22) to engage over a rung and prevent downward movement of the device when the device is moved against said side of the ladder. 9. A safety device as claimed in claim 8 characterised in that the abutment (15) forms part of a side member (12) which when the device is mounted on a ladder extends across the front face of the ladder parallel to the rungs (22) , a second side member (13) being located across the opposite face of the ladder, the device also including end members (10,11) spacing the side members (12,13) apart and of a length greater than the depth of the ladder rung stiles (21) to permit movement of the abutment (15) towards or away from the plane of the rungs (22) so that, in the latter position the device can move along the ladder. 10. A safety device as claimed in claim 8 or 9 characterised in that the frame (10-13) of the safety device is substantially rectangular and planar but with the abutment (15) angled relative to the remainder of the frame. 11. A safety device as claimed in claim 10 characterised in that the angle is approximately 20°. 12. A safety device as claimed in claim 10 characterised in that the other side member (13) mounts centrally a spring clasp (14) for attachment cf a harness thereto. - c - , ?I 13. A safety device for use on ladders substantially as hereinbefore described with reference to the accompanying drawings. 'ϊ

Inventors: SMITH SAMUEL DAVID
Applicants: SMITH SAMUEL DAVID
Application year: 1982
Main classification: E06C7
IPC codes: E06C7