SECURITY GEAR ADAPTED TO BE WORN BY AN OPERATOR TO BE SECURED FROM FALLING OFF AN AERIAL WORK PLATFORM

Abstract

 Security gear (14) to be worn to be secured from falling off a platform (12), comprising:
- a harness (16);
- a lanyard (18) having a first end and (19) a second end (21), the first end (19) being attached to the harness (16) and the second end (21) having a fastening device (22) for fastening the security gear (14) to the platform;
- a harness connection signalling device (20) for signalling a secure connection of the harness (16) to the platform, said signalling device (20) being a plugin cable having an end (25) with a plug (24), the plug fitting into a socket (30) in the platform, the cable also having an end (23) attached to the harness;
wherein the plug (24) has a trigger element (48) to trigger a harness connection sensor arranged in said socket (30) when the plug (29) is plugged in, thus signalling a secure connection of the harness (16) to the platform (12).

Description

[0001] The present invention relates to a security gear adapted to be worn by an operator to be secured from falling off an aerial work platform, comprising:

• a security harness adapted to be donned by the operator;
• a security lanyard having a first fastening end and a second fastening end, the first fastening end being attached to the security harness and the second fastening end having a fastening device for fastening the security gear to the aerial work platform; and
• a harness connection signalling device for signalling a secure connection of the security harness to the aerial work platform, said harness connection signalling device being a plugin cable having a plugin end with a plug, the plug being adapted for fitting into a socket arranged in the aerial work platform, the plugin cable also having a fastening end attached to the security harness.

[0002] Such a security gear is known from WO 00/19052 A1 (D1). This document discloses an operator with a security harness 811, as shown in Fig. 8, secured via a lanyard 804 to an aerialift basket. The operator wearing the security harness 811 is secured via the lanyard 804 from falling off the basket.

[0003] The lanyard 804 has a first snap-hook 803 at one end and a second snap-hook 808 at the other end. The lanyard 804 is attached via the first snap-hook 803 to the basket, and via the second snap hook 808 to the security harness 811.

[0004] The security gear shown in Fig. 8 of D1 includes a lanyard connection detector for detecting proper attachment of the lanyard 804 to the operator. This detector comprises a multi-wire cable 806 plugged with one end into a connector 805 arranged in the basket, and having a magnetic sensor 807 at the other end. The end with the magnetic sensor 807 is attached to the lanyard 804 close to the second snap hook 808. The detector also comprises a permanent magnet 810 attached to the harness 811. The permanent magnet 810 is supposed to magnetise the second snap hook 808 when the same is fastened to the harness 811.

[0005] This magnetisation is detected by the magnetic sensor 807. The detection of a magnetic field by the magnetic sensor 807 is taken as an indication that the operator is successfully secured to the basket.

[0006] However, this known lanyard connection detector might not always correctly detect the presence of a secure connection between the lanyard 804 and the security harness 811. Indeed, the magnetic sensor 807 of the lanyard 804 might indicate that the operator is not secured even if he is secured.

[0007] This can happen if the magnetic field created by the permanent magnet 810 is too weak or too distant in order to properly magnetise the correctly fastened second snap hook 808, meaning that the magnetic sensor will fail to signal that the operator is properly secured. For example, the permanent magnet 810 may be at least partially destroyed. In this situation, the operator will have to manually adjust the position of the fastened second snap hook 808, hoping that the magnetic sensor will finally detect a magnetic field.

[0008] The lanyard connection detector of Fig. 8 of D1 has a further drawback in that it requires a dedicated signalling cable 806. On top of that, the second snap hook 808 needs to be made of a special metal that can be easily magnetised by the permanent magnet 810.

[0009] Document WO 2012/109444 A2 (D2) presents further devices for detecting that an operator is safely secured via a lanyard 156 to an aerial lift basket 152. All of these devices lack a separate plugin cable such as the cable 806 of document D1.

[0010] In view of documents D1 and D2, and in particular in view of the above drawbacks of the lanyard connection detector of Fig. 88 of D1, it is an object of the present invention to provide the above-defined security gear with a more reliable and simplified harness connection signalling device.

[0011] According to the invention, this object is achieved in that the plug has an integrated trigger element adapted to trigger a harness connection sensor arranged in said socket when the plug is plugged into said socket, thus signalling a secure connection of the security harness to the aerial work platform.

[0012] By providing a plug with an integrated trigger element, the operator can signal a secure connection between the security harness and the aerial work platform by simply plugging the plug into a socket of the aerial work platform. Thanks to the plug/socket interface there is a well-defined relative position between the trigger element and the harness connection sensor, which leads to a more reliable triggering of the sensor.

[0013] Furthermore, with the inventive security gear, one can use any desired type of security lanyard. Unlike in the embodiment of Fig. 8 of D1, there is no need for a special "magnet-friendly" snap hook.

[0014] Also, by displacing the harness connection sensor into the aerial work platform, the plugin cable can be a simple mechanical fastening cable and does not have to be an electrical signal transmission cable.

[0015] According to preferred embodiments, the inventive security gear may include one, several or all of the following features, in all technically feasible combinations:

• the trigger element is a permanent magnet;
• the plugin cable is a mechanical fastening cable, such as a metal wire;
• the plug has a first fastening apparatus, such as a pair of opposite fastening studs, for fastening the plug to the socket.

[0016] The invention further relates to an aerial work platform having a basket for holding and lifting an operator, said basket comprising:

• an anchor point for fastening one end of a security-lanyard of a security harness of the operator thereto; and
• a socket for receiving a plug of a plugin cable attached to said security harness, characterised:
• in that said socket has a harness connection sensor arranged therein, said harness connection sensor being adapted to be triggered by said plug when inserted in the socket; and
• by a sensor signal transmitting device adapted to transmit a harness connection signal from said harness connection sensor, when triggered, to a platform control unit (32) adapted to control the operation of the aerial work platform.

[0017] According to preferred embodiments, the inventive aerial work platform may include one, several or all of the following features, in all technically feasible combinations:

• the socket includes a second fastening apparatus, such as a pivoting fastening bracket, for fastening said plug to the socket;
• said harness connection sensor is a magnetic sensor such as a reed sensor or a hall effect sensor;
• said harness connection sensor is part of a safety relay module;
• the sensor signal transmitting device is an electrical cable.

[0018] The invention further relates to a fall protection system for protecting an operator from falling from an aerial work platform, the system comprising:

• security gear as defined above;
• an aerial work platform as defined above;
• said platform control unit;
• a turn-on switch for turning on the aerial work platform, which is connected to said platform control unit; and
• an alarm device, such as an alarm horn, for warning the operator that he or she is not properly secured to the aerial work platform, which is connected to said platform control unit;

wherein the platform control unit is adapted to:

• upon activation of the turn-on switch and absence of a harness connection signal from the harness connection sensor, activate the alarm device and/or disable the aerial work platform; and
• upon presence of a harness connection signal from the harness connection sensor, deactivate the alarm device and/or enable the aerial work platform.

[0019] Exemplary embodiments of the invention will now be described in detail with reference to the drawings, wherein:

Figure 1 shows a schematic representation of the fall protection system according to the invention comprising the security gear and the aerial work platform and;

Figure 2 illustrates a side view of the plug and the socket.

[0020] With reference to figure 1, there is shown a fall protection system 10 for protecting an operator (not shown) from falling from an aerial work platform 12. The operator has to wear a security gear 14 (identified by the dotted line) in order to be protected from falling from the aerial work platform. The security gear 14 comprises a security harness 16, a security lanyard 18 and a harness connection signalling device 20.

[0021] The security lanyard 18 comprises a fastening device 22 for fastening the security gear to the aerial work platform 12.

[0022] The harness connection signalling device 20 comprises a plug 24 for verification whether the operator is secured to the aerial work platform 12.

[0023] The security gear 14 and its components will be described later in more detail.

[0024] The aerial work platform 12 comprises a basket 26 for holding and lifting the operator. The basket 26 is lifted by a lifting device (not shown).

[0025] An anchor point 28 is arranged on the aerial work platform 12 for fastening the security lanyard 18. A socket 30 is arranged on the aerial work platform for receiving the plug 24 of the harness connection signalling device 20.

[0026] The aerial work platform 12 and its components will be described later in more detail.

[0027] The socket 30 is adapted for communicating a signal to a platform control unit 32.

[0028] The platform control unit 32 is electrically connected to an alarm device 34 adapted to indicate whether the operator is not secured, and to a turn-on switch 36 adapted to activate the platform control unit 32 and the basket 26.

[0029] The platform control unit 32, the alarm device 34 and the turn-on switch 36 will be described later in more detail.

[0030] The fall protection system 10 comprises an electrical power source (not shown) electrically connected to the turn-on switch 36.

[0031] The turn-on switch 36 is arranged in the fall protection system 10 such that the operator can actuate the turn-on switch from the outside of the aerial work platform 12. Preferably, the turn-on switch is located on wall in proximity to the aerial work platform 12.

[0032] The turn-on switch has a closed position and an opened position. In the closed position, the turn-on switch 36 is adapted to close an electrical circuit (not shown) adapted to supply electrical power from the electrical power source to the platform control unit 32 and to the lifting device in order to lift or to lower the basket 26. In other words, the turn-on switch 36 is adapted for turning on the aerial work platform 12. This means the aerial work platform is supplied with electrical power by the electrical power source and can be used for lifting an operator.

[0033] In the opened position, the turn-on switch 36 is adapted to stop electrical power supply between the electrical power source and the platform control unit 32 and/or the lifting device.

[0034] The platform control unit 32 is arranged for example on the aerial work platform 12.

[0035] The platform control unit 32 is connected via a sensor signal transmitting device 40 to the socket 30 of the aerial work platform 12 in order to receive a harness connection signal. The sensor signal transmitting device 40 will be explained later.

[0036] The platform control unit 32 is adapted to analyse the harness connection signal received from the socket 30. The platform control unit 32 is adapted to control the lifting device (not shown) in order to lift or to lower the aerial work platform 12.

[0037] The platform control unit 32 is electrically connected (not shown) to the lifting device (not shown). The platform control unit 32 has a command unit 33 adapted to allow an operator to command the lifting device.

[0038] The platform control unit 32 is electrically connected to the alarm device 34 and adapted to activate or deactivate the alarm device 34 in order to warn the operator, depending on the harness connection signal, that the security gear is not attached to the aerial work platform. The warning of the operator can be for example an acoustical warning signal emitted from the alarm device 34. The warning can also be an optical warning signal or other type of warning signal.

[0039] The alarm device 34 of the fall protection system 10 is for example an alarm horn. Additionally, the alarm device 34 may comprise a warning light. The alarm device 34 is adapted to warn the operator when he or she is not properly secured to the aerial work platform 12.

[0040] The basket 26 of the aerial work platform 12 allows holding and lifting of the operator. The basket 26 comprises a ground 27 adapted for the operator to stand on, and a lateral safety enclosure 29 for the operator to hold on. The lateral safety enclosure can be switched from a closed position to an opened position to increase the free moving space. The lateral safety enclosure has a maximum height HR comprised between 80 cm and 150 cm measured from the ground of the basket 26 in the closed position and comprised between 30 cm and 70 cm in the opened position.

[0041] The basket 26 is lifted via the lifting device which is for example a scissor lifting device (not shown) including an electrical motor (not shown) for deploying and retracting the scissor lifting device in order to lift and lower the basket 26.

[0042] The anchor point 28 of the aerial work platform 12 is arranged for example on the lateral safety enclosure 29 at a height HA comprised between 80 cm and 120 cm measured from the ground of the basket 26, particularly when the lateral safety enclosure is in the closed position. The anchor point 28 is for example a metallic eye adapted to receive a hook. The anchor point 28 is adapted for fastening one end of the security lanyard 18 of the security harness 16 of the operator thereto.

[0043] Figure 2 shows a detailed view of the socket 30. The socket 30 of the aerial work platform 12 is arranged for example also on the lateral safety enclosure 29 at a height HS comprised between 80 cm and 120 cm measured from the ground of the basket 26, particularly when the lateral safety enclosure is in the closed position.

[0044] The socket 30 is connected to the platform control unit 32 in order to communicate with the platform control unit 32 via a sensor signal transmitting device 40. The sensor signal transmitting device 40 is adapted to transmit a harness connection signal from a harness connection sensor 46, when triggered, to the platform control unit 32. The harness connection sensor 46 will be described later.

[0045] The sensor signal transmitting device 40 can be an electrical cable.

[0046] The socket 30 is adapted to receive the plug 24 of the security gear 14.

[0047] The socket 30 comprises a fastening apparatus 42, for example a pivoting fastening bracket having an opened position and a closed position. In the opened position the plug 24 can be connected to the socket 30 or removed from the socket 30. In the closed position, the plug 24 cannot be connected to the socket 30 or removed from the socket 30. Thus, the fastening apparatus 42 is adapted to secure the plug 24 to the socket 30 in order to avoid accidental removal of the plug 24. The fastening apparatus 42 is for example complementary to another fastening apparatus (such as a pair of opposite fastening studs) 44 arranged on the plug 24 in order to maintain the plug 24 when the fastening apparatus 42 is in its closed position. The fastening apparatus 44 of the plug 24 is defined as a first fastening apparatus, and the fastening apparatus 42 of the socket 30 is defined as a second fastening apparatus.

[0048] The socket 30 comprises the harness connection sensor 46 which is arranged therein.

[0049] The harness connection sensor 46 is electrically connected to the sensor signal transmitting device 40. The harness connection sensor 46 is for example a magnetic sensor such as a reed switch or reed sensor or a hall effect sensor.

[0050] The harness connection sensor 46 is adapted to be triggered by the plug 24 when inserted in the socket 30.

[0051] The harness connection sensor 46 can be part of a safety relay module (not shown).

[0052] Part of the safety relay module can be arranged in the platform control unit 32. The safety relay module allows triggering the alarm device 34.

[0053] The security gear 14 is adapted to be worn by the operator in order to secure him or her from falling off the aerial work platform 12. The security gear 14 comprises the security harness 16 adapted to be donned by the operator, for example attached around the operator's hip, or around the upper part of the operator's body.

[0054] The plug 24 of the harness connection signalling device 20 is mechanically connected to the security harness 16. The plug 24 is for example parallelepiped-shaped. The plug 24 is adapted to be inserted in the socket 30. The first fastening apparatus 44 is complementary to the second fastening apparatus 42 and consists for example of two studs arranged on two opposite sides of the plug 24.

[0055] The plug 24 has a trigger element 48 integrated into the plug which is adapted to trigger the harness connection sensor 46 when the plug is plugged into the socket 30. The plug 24 is adapted for signalling a secure connection of the security harness 16 to the aerial work platform 12. The trigger element 48 can be a permanent magnet.

[0056] The security lanyard 18 is permanently fastened with a first fastening end 19 to the security harness 16. Alternatively, this first fastening end 19 is for example fastened to the security harness via a carabiner.

[0057] A second fastening end 21 of the lanyard 18 is equipped with the fastening device 22, for example a carabiner. The fastening device 22 is adapted to be fixed to the anchor point 28 of the aerial work platform 12. The fastening device 22 can be made out for example of aluminium, or other metals.

[0058] The fastening device 22 is adapted for fastening the security gear 14 to the aerial work platform 12.

[0059] The harness connection signalling device 20 is a plugin cable, for example a mechanical fastening cable, such as a metallic or non-metallic wire.

[0060] The harness connection signalling device 20 is permanently fastened with a fastening end 23 to the security harness 16. This fastening end 23 is, for example, provided with a plug having at least two pins for fastening the harness connection signalling device 20 with the security harness 16.

[0061] A second end 25, called plugin end of the harness connection signalling device 20 is equipped with the plug 24. The plug 24 may have two connection pins. In particular, it may be a 6 pin plug manufactured by Harting.

[0062] The functioning of the fall protection system 10 will be described now.

[0063] At first, the operator dons the security gear 14, in particular the security harness 16. Then, he turns on the turn-on switch 36 and enters the basket 26 of the aerial work platform 12.

[0064] When the turn-on switch 36 is switched on, the platform control unit 32 verifies whether the harness connection sensor 46 of the socket 30 is sending a harness connection signal to the platform control unit 32.

[0065] When the turn-on switch 36 is switched on, the basket 26 of the aerial lifting platform 12 can be lifted or lowered.

[0066] If no harness connection signal is received by the platform control unit 32, the platform control unit 32 concludes that the harness 16 is not secured to the aerial work platform 12. Then, the platform control unit 32 activates the alarm device 34 in order to warn the operator that he or she is not secured to the aerial work platform 12.

[0067] Once the operator is in the basket 26 he or she locks the fastening device 22 into the anchor point 28 of the aerial work platform 12.

[0068] Then the operator inserts the plug 24 into the socket 30 and the trigger element 48 located in the plug 24 triggers the harness connection sensor 46 in the socket 30.

[0069] When the plug is plugged into the socket 30, the harness connection sensor 46 sends a harness connection signal to the platform control unit 32, thus signalling a secure connection of the security harness to the aerial work platform.

[0070] The operator then puts the second fastening apparatus 42 into its closed position which allows interlocking with the first fastening apparatus 44 in order to avoid accidental removal of the plug 24.

[0071] When the platform control unit 32 receives the harness connection signal, the alarm device 34 is deactivated.

[0072] Finally, the operator notices that the warning signal has disappeared and can start working on the aerial work platform 12 knowing him or her-self in security.

[0073] The operator can command the lifting device via the command unit 33 of the platform control unit 32 in order to lift or to lower the basket 26 of the aerial work platform 12.

[0074] The basket 26 can be lifted or lowered with help of the lifting device (not shown) independently whether the operator is secured or not. This allows to lift or to lower the basket 26 even when the harness connection sensor 46 has a malfunction.

[0075] In an alternative embodiment, the lifting device allows lifting or lowering of the aerial work platform 12 only if the harness connection signal is received by the platform control unit 32. This means that the aerial work platform can only be moved if the turn-on switch 36 is on and additionally, the plug 24 is inserted into the socket 30. This allows protecting the operator from moving the basket 26 when he or she is not secured to the aerial work platform 12.

[0076] In a different embodiment, the sensor signal transmitting device 40 may be a wireless signal transmitting module.

[0077] In this case, the socket 30 comprises a wireless transmitter for transmitting the harness connection signal to the platform control unit 32 and the platform control unit 32 comprises a wireless receiver for receiving the harness connection signal. The wireless signal transmitting module has the advantage to avoid a cable communication to the platform control unit 32.

[0078] It should be noted that the invention is not limited to the above embodiments.

Claims

1. Security gear (14) adapted to be worn by an operator to be secured from falling off an aerial work platform (12), comprising:

- a security harness (16) adapted to be donned by the operator;

- a security lanyard (18) having a first fastening end and a second fastening end, the first fastening end being attached to the security harness (16) and the second fastening end having a fastening device (22) for fastening the security gear (14) to the aerial work platform (12); and

- a harness connection signalling device (20) for signalling a secure connection of the security harness (16) to the aerial work platform (12), said harness connection signalling device (20) being a plugin cable having a plugin end with a plug (24), the plug being adapted for fitting into a socket (30) arranged in the aerial work platform (12), the plugin cable also having a fastening end attached to the security harness (16);

characterised in that the plug (24) has an integrated trigger element (48) adapted to trigger a harness connection sensor (46) arranged in said socket (30) when the plug is plugged into said socket, thus signalling a secure connection of the security harness (16) to the aerial work platform (12).

2. Security gear according to claim 1, wherein the trigger element (48) is a permanent magnet.

3. Security gear according to claim 1 or claim 2, wherein the plugin cable is a mechanical fastening cable, such as a metal wire.

4. Security gear according to any one of the previous claims, wherein the plug (24) has a first fastening apparatus (44), such as a pair of opposite fastening studs, for fastening the plug (24) to the socket (30).

5. An aerial work platform (12) having a basket (26) for holding and lifting an operator, said basket comprising:

- an anchor point (28) for fastening one end of a security-lanyard (18) of a security harness (16) of the operator thereto; and

- a socket (30) for receiving a plug (24) of a plugin cable attached to said security harness (30),

characterised:

- in that said socket (30) has a harness connection sensor (46) arranged therein, said harness connection sensor being adapted to be triggered by said plug (24) when inserted in the socket (30); and

- by a sensor signal transmitting device (40) adapted to transmit a harness connection signal from said harness connection sensor (46), when triggered, to a platform control unit (32) adapted to control the operation of the aerial work platform (12).

6. The aerial work platform of claim 5, wherein the socket (30) includes a second fastening apparatus (42), such as a pivoting fastening bracket, for fastening said plug (24) to the socket (30).

7. The aerial work platform of claim 5 or 6, wherein said harness connection sensor (46) is a magnetic sensor such as a reed sensor or a hall effect sensor.

8. The aerial work platform of any one of claims 5 to 7, wherein said harness connection sensor (46) is part of a safety relay module.

9. The aerial work platform of any one of claims 5 to 8, wherein the sensor signal transmitting device (40) is an electrical cable.

10. A fall protection system for protecting an operator from falling from an aerial work platform (12), the system comprising:

- security gear (14) according to any one of claims 1 to 4;

- an aerial work platform (12) according to any one of claims 5 to 9;

- said platform control unit (32);

- a turn-on switch (36) for turning on the aerial work platform, which is connected to said platform control unit; and

- an alarm device (34), such as an alarm horn, for warning the operator that he or she is not properly secured to the aerial work platform, which is connected to said platform control unit (32);

wherein the platform control unit is adapted to:

- upon activation of the turn-on switch (34) and absence of a harness connection signal from the harness connection sensor (46), activate the alarm device (34) and/or disable the aerial work platform (12); and

- upon presence of a harness connection signal from the harness connection sensor (46), deactivate the alarm device (34) and/or enable the aerial work platform (12).

Drawing