EP3747802B1

EP3747802B1 - Safety system for an underground refuse collecting apparatus

Info

Publication number: EP3747802B1
Application number: EP19178838.9A
Authority: EP
Inventors: Paul VERHESEN
Original assignee: ESE World BV
Current assignee: ESE World BV
Priority date: 2019-06-06
Filing date: 2019-06-06
Publication date: 2023-08-02
Anticipated expiration: 2039-06-06
Also published as: EP3747802C0; EP3747802A1; EP3747802A8; ES2956807T3

Description

The present invention relates to a safety system for an underground refuse collecting apparatus according to the preamble of independent claim 1. Furthermore, according to the preamble of independent claim 10, the invention is directed to such an underground refuse collecting apparatus itself.
Underground refuse collecting apparatus per se are well known in the prior art. They usually comprise a receiving pit which serves as an external housing which is placed into the ground. In its mounted state, the receiving pit is located at least partially under the ground level. The receiving pit serves on the one hand to keep ground water out. On the other hand, it also serves as a protection to keep soil out and maintain the contour of the apparatus as a whole.
A refuse container is provided inside the receiving pit. In order to enable the refuse container to get emptied out, a removing device is provided by means of which the refuse container can be removed out of the receiving pit.
While the refuse container is located outside the receiving pit, a safety system is activated, which may comprise a safety platform, by means of which the pit opening and therefore the empty receiving pit can get closed in order to prevent any accidents such as people falling into the empty receiving pit.
Safety systems as such are also well known in the prior art. They are available in different configurations.
According to one known solution in general prior art, a safety system which may cover the pit opening, comprises one or more hinged doors. These doors are closed by a spring-loaded lock, providing sufficient force to close the door. The doors are mechanically locked for withstanding a required point-load. The disadvantage of such a solution is that when the lock is broken, for example when the mobile refuse container is placed back with too much force and not being aligned with the locking mechanism, the lock will break and the doors only remain closed by the relatively weak spring-load. This load is insufficient to withstand the 2500N of point pressure and a person walking over the safety platform could apply sufficient force to make the doors function as a trap, closing the doors behind the person falling into the pit. NL1028372C2 discloses a safety floor for covering a receiving pit for a waste recycling container, which is held in a raised position by means of a counterweight. This solution describes a safety floor that is lifted with 250kg of counterweight. The disadvantage of such a system is that the 250kg metal counter weight creates an important increase of costs due to the raw metal weight price. Furthermore, the carrying capacity of the safety floor might be too small in its corners which increases the danger of injuries.
Different solutions known in the prior art use pneumatic spring devices in order to move a safety platform, which supports the refuse container, from the bottom of the receiving pit to the top of the receiving pit. Usually, such pneumatic spring devices are mounted below the safety platform. It is a drawback of such solutions that the pneumatic spring devices lose their force over their life-span, such that the safety platform is no longer placed in the correct position, if the waste container is removed from the receiving pit, which is pretty dangerous.
A safety platform having a spring-loaded locking mechanism is disclosed in EP2006221A1 . However, this locking mechanism is provided as a latch finger. Such mechanical locking devices have the drawback, that, if they are not correctly unlocked, when the refuse container is placed back on the safety platform in order to get removed into the receiving pit, the latch fingers can get damaged, bended out of shape for example. Other locking mechanisms for safety platforms are known from FR2984859 and FR2736901 .
Document DE4105901A1 , from which the present invention departs, discloses a safety platform which is moved by means of straps. The movement of the straps is performed by means of a motor or by means of muscular power, which is structurally complex and therefore cost intensive in the first case, and at least uncomfortable in the second case.
A safety platform according to the preamble of claim 1 is disclosed by FR2846312 .
Therefore, it is the object of the present invention to provide a low cost reliable multiple safety mechanism to cover the receiving pit of an underground refuse collecting apparatus, when the refuse container is removed of the receiving pit, for emptying or maintenance matters for example.
In accordance with the present invention, this object is solved according to a first aspect of the invention by the safety system with the features according to independent claim 1, and, according to a second aspect of the present invention, by the underground refuse collecting apparatus with the features according to independent claim 10.
Additional features and details of the present invention become apparent from the dependent claims, from the description and from the drawings.
Therein, features and details which are described in connection with one of the aspects according to the invention apply with respect to their disclosure in their entirety also to the other aspect according to the invention, so that statements made with respect to the first aspect of the invention also apply to their full extent to the second aspect of the invention, and vice versa.
All different aspects of the present invention underlie the same common basic idea, which comprises a safety platform, a safety floor for example, for covering the receiving pit of an underground refuse collecting apparatus, brought to raised position by means of at least one elastic body and being locked in position.
According to the present invention, a safety platform in brought into a raised position in order to cover the pit opening of the receiving pit of the underground refuse collecting apparatus, when the underground refuse container is removed from the receiving pit. The lifting procedure of the safety platform is performed by means of a system of elastic strands, raising the safety platform to a level where it protects pedestrians from falling into the receiving pit. Once the safety platform reaches the desired position, a spring-loaded locking mechanism locks the safety platform in position until the mobile refuse container is lowered back into the receiving pit.
In order to prevent people from falling into the receiving pit of a removed underground refuse mobile container, according to the present invention, a multiple safety system is provided to cover the receiving pit, in particular the pit opening thereof. It consists of an elastic spring-loaded safety platform in combination with a static load resisting locking mechanism without the risk that the lock is overloaded while misplacing the mobile refuse container.
In particular the safety system according to the present invention fulfils the requirements of EN13071, which requires a load capacity of 150kg for the safety platform. According to this European Norm, the equipment is composed of a device whereby a weight of 150 kg shall be applied vertically, on a surface of maximum ^~300 mm" diameter. The test method: is as follows: the weight of 150 kg shall be applied on a minimum of 8 points of the safety platform. When selecting the locations, the design of the safety platform shall be considered and the test shall be focused on the areas most vulnerable to movement or breakage. The minimum duration of each test shall be 1 minute
The aforementioned goals are achieved by an interaction of different components, in particular by the interaction of a special safety platform in combination with a special lifting device for the safety platform and in combination with a special locking device for holding the safety platform in a defined position.
In the prior art, the focus was laid on either one of the aforementioned components only. It was the merit of the inventors of the present invention that they developed a low-cost solution which however fulfils the strict requirements of EN13071, by combining different components to one single safety system.
The present invention is directed to the technical field of underground refuse collecting apparatus.
In particular, such an underground refuse collecting apparatus comprises a receiving pit, which serves as an exterior housing and which is placed inside the ground, such that the receiving pit is located at least partially below the ground level. Preferably, the receiving pit is square or rectangular in shape, which means that it has a square or rectangular cross-section. The receiving pit, which may be made of concrete, metal, steel for example, a plastic material, or the like, preferably comprises a pit side wall, optionally a pit ground or pit bottom at the lower end of the pit side wall and a pit opening at the upper end of the pit side wall. The aforementioned components preferably delimit a receiving space, said receiving space being adapted for receiving a, in particular mobile, refuse container, said refuse container serving as a refuse collecting container. The volume of the refuse container can range from 1m³ to 5m³. However, the present invention is not limited to specific load capacities for the refuse container. Preferably, the refuse container is adapted for temporarily storing waste, valuable substances or the like. On the one hand the receiving pit serves to keep ground water out of the underground refuse collecting apparatus. On the other hand, it also serves as a protection to keep soil out and maintain the contour of the arrangement as a whole.
The refuse container is movably located inside the receiving pit. That means that the refuse container can get removed, via said pit opening, out of the receiving pit. In the same way, the refuse container can get inserted, once it has been emptied, maintained or the like, via said pit opening into the receiving pit as well.
Preferably, the refuse container comprises a lid element that covers the refuse container at the top, the lid element having a receiving opening for refuse. The refuse container which is located inside the receiving pit and hence at least partially below ground level, when the underground refuse collecting apparatus is in use in the intended manner, serves to actually receive the refuse.
To enable a refuse container of this kind to be removed from the receiving pit, in particular to get emptied, a removing device, in particular a handling device, is provided by means of which the refuse container can get handled and can be removed from the receiving pit. In addition, the removing device is also used for inserting and lowering the refuse container into the receiving pit. Therefore, according to a preferred embodiment, the underground refuse collecting apparatus comprises a device for removing the refuse container out of the receiving pit and for placing the refuse container into of the receiving pit.
In the operational state of the underground refuse collecting apparatus, refuse is preferably thrown into the refuse container by means of a chute device, which may comprise a disposal housing for refuse, and which is provided or arranged above the receiving opening of the lid element of the refuse container. The chute device, which preferably comprises a drop.in opening for refuse, is connected to the refuse container. Therefore, according to a different preferred embodiment, the underground refuse collecting apparatus comprises a chute device being assigned to the refuse container and being adapted for receiving refuse to be inserted into the refuse container.
While the refuse container is located outside the receiving pit, a safety system is activated, said safety system comprising a safety platform, by means of which the empty receiving pit, in particular the open pit opening, is or remains closed, in order to prevent accidents, in particular to prevent people from falling into the receiving pit. Preferably, the safety platform is square or rectangular in shape, which means that it has a square or rectangular cross-section.
According to a preferred embodiment, the underground refuse collecting apparatus comprises a receiving pit, said receiving pit comprising a pit side wall and a pit opening for receiving a refuse container, and optionally a pit ground or bottom. These components delimit a receiving space or an uptake chamber for receiving and storing the refuse container. The apparatus according to this preferred embodiment further comprises a refuse container being movably arranged inside the receiving pit, and a safety system for closing the pit opening, once the refuse container has been removed from the receiving pit. Furthermore, the safety system is preferably adapted for supporting the refuse container whilst it is placed inside the receiving pit.
According to the first aspect, the present invention is directed to the safety system comprising the features of independent claim 1.
The safety system is used in connection with an underground refuse collecting apparatus, in particular for an underground refuse collecting apparatus as described further above.
As a first key component, the safety system comprises a safety platform. This safety platform which will be explained in more detail further below, serves as a safety floor, if the refuse container has been removed from the receiving pit. In this situation the safety platform covers the pit opening of the receiving pit. According to a different or additional function, the safety platform is used for holding and supporting the refuse container, if the refuse container is or gets placed inside the receiving pit. That means, that the refuse container is set down on the safety platform when it gets stored and located inside the receiving pit.
As a second key component, the safety system comprises a lifting device for moving the safety platform between different positions. Preferably, by means of said lifting device, which will be described in more detail further below, the safety platform of the safety system is movably mounted inside the receiving pit between a first ground position, in which the refuse container is stored inside the receiving pit, and a second safety position in which the refuse container is removed from the receiving pit and in which the pit opening is closed by the safety platform. In the first ground position the safety platform is preferably located at the lower end of the receiving pit, on the ground or bottom of the receiving pit or in close vicinity to the ground or bottom for example. According to a different embodiment, the safety platform can be located in a distance to the ground or bottom in this first ground position, which allows the arrangement of further components of the underground refuse collecting apparatus below the safety platform. In the second safety position, the safety platform is preferably located at the upper end of the receiving pit in particular such that it is aligned with the upper edge of the receiving pit.
According to the present invention, the lifting device comprises a number of elastic strands. In particular, a strand is a member which extends linearly in a certain length. In particular, a strand is an elongated member having an extension in a length direction which is a multiple of its extension in width direction. The present invention is not limited to specific types of strands. For example, a rope, a cord, a string, a band or a cable can be a strand according to the present invention. In a preferred embodiment, the strand is provided as a cable or as a band.
According to the present invention the strand is provided as an elastic strand. That means that the strand has elastic properties which will be explained in more detail further below.
According to the present invention the lifting device comprises a number of such elastic strands, which means that the lifting device comprises more than one such elastic strands. The present invention is not limited to a specific number of elastic strands. According to a preferred embodiment, the lifting device comprises four elastic strands. Nevertheless, the number of elastic strands used as a lifting device for the safety platform is dependent on the strand material and/or on the width of the elastic strands and/or on the load to get lifted by means of said lifting device.
Each of the elastic strands is connected to the safety platform, via a first end thereof for example.
As a third key component, the safety system further comprises at least one spring-loaded locking device. This spring-loaded locking device, which will be explained in more detail further below, is provided in such a way that it is capable of for holding the safety platform in a defined position, said spring-locking device being mounted to the safety platform.
Next, the safety platform will be described in more detail. The present invention is not limited to specific types of safety platforms. It is the general function of the safety platform to provide some kind of a safety floor, which covers the pit opening of the receiving pit, when the refuse container has been removed from the receiving pit.
For example, the safety platform can be provided as a single-component member having the platform element only, said platform element being preferably made of a rigid material.
According to a preferred embodiment the safety platform is provided as a multicomponent structure consisting of more than one component. According to this embodiment, it is preferably provided that the safety platform comprises a platform frame and a platform surface, said platform surface being surrounded by said platform frame. For example, the platform surface can be inserted into and inside the platform frame. According to a different embodiment, the platform surface is mounted on the platform frame.
The safety platform, in particular the platform surface and/or the platform frame, is/are preferably made from a lightweight material. Alternatively, or in addition, the platform surface can be a net and/or a mesh. According to a preferred embodiment, the safety platform, in particular the platform surface and/or the platform frame, is(are made out of a low weight material to reduce the number of elastic strands needed to lift the safety platform. For example, It can be made out of a mesh of fabric straps/bands, and/or a plastic sheet, mesh/ bands, and/or of light weight sheet material such as glass fibre/ carbon, and/or of elastic fabrics/nets, which are used for trampolines for example, and/or of metal wire mesh, nets, and/or of any other lightweight material.
According to a preferred embodiment, the platform surface is carried by the platform frame, which preferably is a rigid frame, that also accommodates the spring-loaded locking device.
According to a preferred embodiment, the elastic strands are connected to the safety platform at the edges thereof. For example, if the safety platform is rectangular or square in shape, the elastic strands can be connected to the safety platform in the four corners thereof. In this case the lifting device preferably comprises four elastic strands.
According to yet another preferred embodiment, at least one of the elastic strands, preferably all of the elastic strands, is/are guided over a guidance device, in particular over a guidance reel. Preferably the guidance device is connected to or arranged at the receiving pit.
According to a preferred embodiment, each of the elastic strands comprises two ends. With one of its ends, which is the first end, the elastic strands are connected to the safety platform. The guidance device is preferably arranged at the receiving pit, in particular at the upper edge thereof, said upper edge preferably bordering the pit opening. To each of the elastic strands, one guiding device is assigned respectively. The elastic strands are guided over the guiding device and get redirected in the direction of the pit ground or bottom. With the other end, which is the second end, the elastic strands are connected to the receiving pit, to the ground or bottom thereof for example.
According to a different embodiment, the elastic strands are connected with their second ends to the guidance device, in particular to a guidance reel. In this case the elastic strands are coiled up on the guidance device when the safety platform is lifted.
Preferably the elastic strands are moving over one or more guidance devices, guidance wheels for example, to enable the use of longer strands for increased stretch length to cover the movement of the height of the pit, while maintaining a proper elastic force onto the safety platform. The other reason for applying guidance devises is to reduce friction and wear of the elastic strands. Alternatively, a smooth surface rod can be applied as a guidance device, which is preferably made of or covered by a smooth metal or plastic material, in order to guide the elastic strands like the function of the wheel described above.
Next, the elastic strands are described in more detail. The present invention is not limited to a specific material, specific configurations and geometries of the elastic strands.
According to a preferred embodiment, the elastic strands have the property of generating elastic restoring forces, in particular of generating progressive restoring forces. If the elastic strands are put under load, in particular if the elastic strands get stretched or elongated into their longitudinal direction, elastic restoring forces are created inside the elastic strands due to their elastic properties. The elasticity of the elastic strands is their property to change their shape, for example to increase their length, due to an applied force, and to return to its original shape once the applied force falls away. According to a preferred embodiment, the elastic strands show a progressive elastic behaviour. Nevertheless, elastic strands having a linear elastic behaviour are suitable as well.
According to a preferred embodiment, the elastic strands of the safety system are provided such that they exert a maximum elastic restoring force, if the safety platform is in the first ground position. In this situation the elastic strands have the maximum elongation. In addition the elastic strands of the safety system are preferably provided such that they exert a reduced, in particular a minimum, elastic restoring force, if the safety platform is in the second safety position.
Preferably the elastic strands are made from an elastic material or are at least partially made from an elastic material. The present invention is not limited to specific types of material. According to a preferred embodiment, the elastic material is selected from the group consisting of rubber, caoutchouc, latex, preferably from 100% natural materials or from synthetic materials.
The elastic strands can be made out of rubber bands or of multi core elastic ropes or of any other elastic material. Preferably, multiple elastic strands are used, such as four pieces to place two of them on each side of the safety platform for balancing. For balancing the fixation of the elastic strands to the safety platform should be close to each corner to resist the forces applied to the safety platform best. To finetune the force applied, and to increase reliability, more elastic strands on both or on all of the sides can be applied. For ease of maintenance the elastic cables are mounted in a way that they are easy to replace. It is preferred to use UV and weather resistant elastic material to prevent a reduced lifting force over lifetime. Additionally, all of the elastic strands could be periodically replaced to guarantee the proper functioning over lifetime.
Alternatively, a combination of non-elastic strands and elastic strands can be used where the elastic part is only covering a certain percentage of the length of the strands. In this case, the non-elastic part can also be made from a steel strand or metal chains.
Next, the spring-loaded locking device will be explained in detail. According to a preferred embodiment, the at least one spring-loaded locking device laterally protrudes from the safety platform, in particular from the platform frame. This means that the spring-loaded locking device extends sideways from the sides of the safety platform, from the platform frame for example. In this case the safety platform and the locking device are preferably aligned with regard to each other. According to different embodiments, the locking device can be mounted below the safety platform, or on the safety platform as well, if appropriate.
The present invention is not limited to a specific number of locking devices. Preferably, more than one locking device is provided. According to a preferred embodiment, the safety system comprises four spring-loaded locking devices, two locking devices each being provided at opposite sides of the safety platform. According to a different embodiment, at least one locking device is provided at each side of the safety platform. The number and arrangement of the locking devices at and over the edge(s) of the safety platform generally depends on the weight to be dealt with.
According to a preferred embodiment, the spring-loaded locking device comprises a spring-loaded wheel. The wheel moves over the inner surface of the receiving pit, when the safety platform is moved between different positions inside the receiving pit, for example between the first ground position and the second safety position. Therefore, the locking device may function as a guiding element for guiding the safety platform inside the receiving pit as well.
In connection with the aforementioned embodiment it is preferably provided that the spring-loaded wheel is mounted to a wheel base. Preferably, the wheel base has a shape that will keep the wheel in vertical position, such as square, rectangular, H profile, I-profile or any other shape that prevents the wheel from rotating around the axis of the wheel base. The wheel base is movably mounted in a receiving recess, said receiving recess being assigned the service platform. A spring member is mounted inside the receiving recess, said spring member interacting with the wheel base. If the wheel and the wheel base are moved inside the receiving recess due to a force applied to the wheel, the spring member inside the receiving recess is compressed, thus creating a restoring force.
According to the second aspect the invention is directed to an underground refuse collecting apparatus comprising the features of independent claim 10. This apparatus comprises a receiving pit, said receiving pit comprising a pit side wall and a pit opening for receiving a refuse container. The apparatus further comprises a refuse container being movably arranged inside the receiving pit, and a safety system for closing the pit opening, once the refuse container has been removed from the receiving pit. According to the present invention, the safety system is provided according to the first aspect of the invention. Therefore, in order to describe and explain the configuration of the underground refuse collecting apparatus as well as its function, full reference is also made to the entire disclosure of the first aspect and to the general description of the apparatus further above.
According to a preferred embodiment, the service platform of the safety system is movably mounted inside the receiving pit between a first ground position, in which the refuse container is stored, preferably completely stored, inside the receiving pit, and a second safety position in which the refuse container is removed from the receiving pit and in which the pit opening is closed by the safety platform.
According to a preferred embodiment, the elastic strands of the safety system are provided such that they exert a maximum elastic restoring force, if the safety platform is in the first ground position. A lower elastic restoring force, in particular a minimum elastic restoring force, may be exerted by the elastic strands, if the safety platform is in the second safety position.
According to a preferred embodiment the pit side wall comprises an interaction device. This interaction device is provided in such a way that it is capable of interacting with the spring-loaded locking device, in particular a spring-loaded wheel thereof. Furthermore, the interaction device is provided in such a way that it is capable of fixing the safety platform in the second safety position. The present invention is not limited to specific types and configurations of such interaction devices. Next a number of preferred embodiments are described in more detail.
According to a preferred embodiment, the interaction device comprises a receiving profile element being mounted to the pit side wall, in particular to the inner surface of said pit side wall, which is directed into the receiving space of the receiving pit. This profile element can be a metal profile mounted on the receiving pit containing a negative cavity at the position where the safety platform should hold position.
According to a different preferred embodiment, the interaction device is provided as recess being formed inside the pit side wall, in particular on the inner surface of the pit side wall. Preferably the recess is provided as a cavity having a concave shape. Preferably, the depth of the recess is slightly deeper than the center of the wheel of the spring-loaded locking device. This will prevent the safety platform to move downward when a force or human weight is applied to any point on the surface of the safety platform. Preferably the recess is embedded in the side wall of the receiving pit.
According to yet another preferred embodiment, the interaction device is provided a projection protruding from the pit side wall, in particular on the inner surface of the pit side wall. Preferably, the projection is a positive geometry coming out of the surface of the pit walls.
Next, a preferred embodiment of the underground refuse collecting apparatus is described. According to this embodiment, the apparatus comprises a static concrete, steel or plastic receiving pit containing a mobile underground refuse container. Volumes can range from 1m³ up to 5m³ of volume or even more. The mobile refuse container is lifted out of the receiving pit, by a crane for example, that is holding the bottom doors of the refuse container closed while lifting. While the refuse container is lifted, a safety platform, a safety floor for example, which is positioned below the mobile refuse container is moving with the mobile refuse container upwards. The safety platform is connected to multiple elastic strands, which are stretched to provide an elastic tensile force in the starting position. When the mobile refuse container is lifted upwards, this elastic tensile force will pull the safety platform upwards. While the safety platform is moving upwards, it is guided in its movement by spring-load wheels of a spring-loaded locking device, that follow the contours of the sides of the receiving pit. When the safety platform is in position, the spring load wheels reach a level where the pit contours contain a recess in the sides of the receiving pit. The wheels will be extended into the cavity by the pushing of the spring, locking the safety platform in a horizontal position. The depth of the recess, which is slightly deeper than the center of the wheel, will prevent the safety platform to move downward when a force or human weight below 2500N of force is applied to any point on the surface of the safety platform. Together with the force from the elastic strands, the safety platform will stay into position. When for any reason the locking mechanism does not function properly, the load applied to the safety platform by the elastic strands will still be strong enough to lift a person and will prevent the person to fall into the receiving pit.
The safety platform is unlocked when the mobile refuse container, having a mass of 250 kg or more for example, is placed back. This weight will force the spring-loaded wheels to move back in the cavity, pushing the wheel base against the direction of the spring load.
When the wheel is pushed inside its receiving recess, the wheel is able to exit the pit recess and the safety platform can again move downwards, following the movement of the mobile refuse container. The elastic strands are stretched placing a load onto the strands for lifting the safety platform upwards in the next cycle of removal of the mobile refuse container.
The present invention as embodied according to the both aspects of the invention has a number of advantages, which are:

Multiple safety system with less mechanically locking parts that can malfunction.
Reduced sensitivity to misplacement of the mobile refuse container that would otherwise cause breakage or malfunctioning of the safety system.
Reduced material use compared to existing solution. This is an important aspect for costs but alsof or transport weight as the total underground waste system is very heavy compared to its transport footprint. Lower weight coudl mean more units on a truck reducing the high transport costs.
Less materials which are sensitive to corrosion in wet, cold, hot and even salty weather conditions.
Reduction of sound compared to moving metal doors and flaps and metal locking mechanisms
Reduced risk on injuries when fabrics/nets are used to create the platform surface.
The safety platform can be made from recycled materials. The parts can be easily replaced and repaired on site and part scan be refurbished and reused for applying the principles of the circular economy
The safety platform can be mounted in existing underground refuse collecting apparatus, which enables to upgrade existing apparatus with a safer solution.

For a better understanding of the present invention, preferred embodiments of the present invention will now be described by way of an example with reference to the accompanying drawings, in which

Figures 1 to 4: depict different handling operation steps with regard to a first embodiment of an underground refuse collecting apparatus according to the present invention;
Figure 5: depicts a second embodiment of an underground refuse collecting apparatus according to the present invention;
Figure 6: depicts an embodiment of a spring-loaded locking device according to the present invention;
Figures 7 to 9: depict different operational steps of the locking device as shown in Figure 6 interacting with an interaction device according to a first embodiment; and
Figures 10a to10c: depict different operational steps of the locking device as shown in Figure 6 interacting with an interaction device according to a second embodiment.

Figures 1 to 4 show a first embodiment of an underground refuse collecting apparatus 10. The apparatus 10 comprises a receiving pit 11, which is placed in the ground 100, such that the receiving pit 11 is located below ground level 101. The receiving pit 11, which is made of concrete, comprises a pit side wall 12, a pit ground 13 and a pit opening 14. The aforementioned components border a receiving space 15. The receiving pit 11 is square or rectangular in shape.
The receiving pit 11 is provided for receiving a refuse container 16, said refuse container 16 having two refuse container doors 17 at the bottom thereof. At the upper side, the refuse container 16 comprises a lid element 18, said lid element 18 having a chute device 19 for inserting waste or valuable substances. Furthermore, the refuse container 16 comprises a removing device 20, said removing device 20 being provided for lifting the refuse container 16 out of the receiving pit 11 and for replacing the refuse container 16 back into the receiving pit 11, once the refuse container 17 has been emptied. In the present embodiment, the removing device 20 is some kind of a hook device which interacts with a corresponding crane device.
The underground refuse collecting apparatus 10 further comprises a safety system 30, said safety system 30 comprising a number of key components. A first key component is a safety platform 40, which is movably mounted inside the receiving pit 11 between a first ground position, as shown in Figure 1, and a second safety position, which is shown in Figure 4. Preferably the safety platform 40 is square or rectangular in shape. The safety platform 40 comprises a platform frame 41 and a platform surface 42 being mounted to the platform frame 41. The platform surface 42 is made of a lightweight material and has a net or mesh structure.
A second key component is a lifting device for lifting the safety platform 40, said lifting device comprising a number of elastic strands 50. In the embodiment shown in Figures 1 to 4, four such elastic strands 50 are provided, each elastic strand 50 being mounted to the square shaped safety platform 40 at a corner thereof. With a first end 51, each elastic strand 50 is connected to the safety platform 40. The elastic strands 50 are guided over guidance reels 53 respectively, each guidance reel 53 being mounted to the receiving pit 11 at the upper edge thereof. By means of said guidance reels 53, the elastic strands 50 are directed back to the pit ground 13, where the elastic strands 50 are connected to the pit ground 13 via their second ends 52 respectively.
When the refuse container 16 is removed from the receiving pit 11, the safety platform 40, on which the refuse container 16 is placed, is lifted upwards due to the restoring forces of the elastic strands 50. When the refuse container 16 is lifted out of the receiving pit 11, as shown in Figure 3, the pit opening 14 is closed by the safety platform 40. A person 102, as shown in Figure 4, can now cross the pit opening 14 being closed by the safety platform 40 without having the risk of falling into the receiving pit 11.
A third key component is a spring-loaded locking device 60 which will be explained in more detail with regard to Figure 6 further below. As shown in the Figures four such spring-loaded locking devices 60 are provided two of them each being arranged at opposite sides of the platform frame 41.
Figure 5 depicts a different embodiment of the underground refuse collecting apparatus 10, which however is similar to the first embodiment shown in Figures 1 to 4. Therefore, the same components are designated with the same reference numerals. With this regard, at this point, full reference is made to the description of Figures 1 to 4. In the following, only the differences between both embodiments are described. Whilst the elastic strands 50 according to Figures 1 to 4 are connected with their second ends 52 to the pit ground 13, the elastic strands 50 according to Figure 5 are connected with their second ends to the guidance reel 53, said guidance reels 53 serving as a member to reeling the elastic strands 50.
Figure 6 depicts a spring-loaded locking device 60, which is mounted to the platform frame 41, said platform frame 41 surrounding the platform surface 42 of safety platform 40.
The spring-loaded locking device 60 comprises a spring-loaded wheel 61, which is mounted to a wheel base 62. The wheel base 62 is slidably mounted inside a receiving recess 63, said receiving recess 63 further housing a spring member 64. If the wheel base 62 is pushed into the receiving recess 63, the spring member 64 gets compressed, thus creating a restoring force.
Figures 7 to 9 depict a first embodiment of how the spring-loaded locking device 60 of Figure 6 is used. As can be seen, the spring-loaded locking device 60 interacts with an interaction device 70. As evident form Figures 7 to 9, the interaction device 70 is provided as a recess 71, said recess 71 being provided as a cavity formed at the inner surface 12a of pit side wall 12., said inner surface 12a being directed to the receiving space 15. The locking device 60 gets activated, if the spring-loaded wheel 61, which runs along the inner surface 12a of the pit side wall 12 comes to rest in the recess 71.
Figures 10a to 10c show a different functional embodiment of the spring-loaded locking device 60 according to Figure 6. As being evident form Figures 10a to 10c, the interaction device 70 is configured in a different way as compared to the interaction device shown in Figures 7 to 9.
According to Figures 10a to 10c, the interaction device 70 comprises a projection 72, which protrudes from the inner surface 12a of the pit side wall12 into the receiving space 15. The locking device 60 gets activated, when the spring-loaded wheel 61, which runs along the inner surface 12a of the pit side wall 12 comes to rest on the projection 72.
In the following the function of the safety system 30 according to the present invention will be explained by making reference to Figures 1 to 10c.
This underground refuse collecting apparatus 10 consists of a static concrete, steel or plastic receiving pit 11 (see for example Figures 3 and 4) containing a mobile underground refuse container 16 (see for example Figure 3). Volumes can range from 1m³ up to 5m³ of volume or even more. The mobile refuse container 16 is lifted out of the receiving pit 11, preferably by means of a crane, that is holding the bottom doors 17 closed (see Figure 3) while lifting. While the refuse container 16 is lifted, a safety platform 40, which is positioned below the mobile refuse container 16 (see for example Figures 1 to 3) is moving with the mobile refuse container 16 upwards. The safety platform 40 is connected to multiple elastic strands 50 (see for example Figures 1 to 5), which are stretched to provide an elastic tensile force in the starting position (Figure 1). When the mobile refuse container 16 is lifted upwards (Figure 2), this elastic tensile force will pull the safety platform 40 upwards. While the safety platform 40 is moving upwards, it is guided in its movement by spring load wheels 61 of spring-loaded locking devices 60 (see Figure 6 to 9 for example), that follow the contours of the sides 12 of the receiving pit 11. When the safety platform 40 is in position, the spring-loaded wheels 61 reach a level where the pit contours contain a recess 71 in the sides 12 of the pit 11. The wheels 61 will be extended into the recess 71 by the pushing of the spring member 64, locking the safety platform 40 in a horizontal position (see Figure 8). The depth of the recess 71, which is slightly deeper than the center of the wheel 61, will prevent the safety platform 40 to move downward when a force or human weight is applied to any point on the surface of the safety platform 40 (see Figure 4) Together with the force from the elastic strands 50, the safety platform 40 will stay into position. When for any reason the locking device 60 does not function properly, the load applied to the safety platform 40 by the elastic strands 50 will still be strong enough to lift a person and will prevent the person to fall into the receiving pit 11.
The safety platform 40 is unlocked when the mobile refuse container 16 with a mass of over 250 kgs is placed back. This weight will force the spring-loaded wheels 61 to move back in the recess 71, pushing the wheel base 62 against the direction of the spring load of spring member 64. The wheel base 62 preferably has a shape that will keep the wheel 61 in vertical position, such as square, rectangular (see Figure 6) , H profile, I-profile or any other shape that prevents the wheel 61 from rotating around the axis of the wheel base 62.
When the wheel 61 is pushed inside its receiving recess 63, the wheel 61 is able to exit the pit recess and the safety platform 40 can again move downwards (see Figure 9), following the movement of the mobile refuse container 16. The elastic strands 50 are stretched placing a load onto the strands 50 for lifting the safety platform 40 upwards in the next cycle of removal of the mobile refuse container 16 (see Figure 1). Instead of a recess 71 (see Figures 7 to 9) the interaction device 70 may be provided as a projection 72 protruding from the pit side wall 12, in particular on the inner surface 12a of the pit side wall 12 (see Figures 10a to 10c). The projection 72 is a positive geometry coming out of the inner surface 12a of the pit side walls 12.

List of reference numerals

10: Underground refuse collecting apparatus
11: Receiving pit
12: Pit side wall
12a: Inner surface of pit side wall
13: Pit ground
14: Pit opening
15: Receiving space
16: Refuse container
17: Refuse container door
18: Lid element
19: Chute Device
20: Removing device

30: Safety system

40: Safety platform
41: Platform frame
42: Platform surface

50: Elastic strand
51: First end
52: Second end
53: Guidance reel

60: Spring-loaded locking device
61: Spring-loaded wheel
62: Wheel base
63: Receiving recess
64: Spring member
70: Interaction device
71: Recess in pit side wall
72: Projection at pit side wall

100: Ground
101: Ground level
102: Person

Claims

A safety system (30) for an underground refuse collecting apparatus (10), said safety system (30) comprising a safety platform (40) and a lifting device for moving the safety platform (40) between different positions, wherein the lifting device comprises a number of elastic strands (50), preferably two or more elastic strands (50), each elastic strand (50) being connected to the safety platform (40), characterized in that the safety system (30) further comprises at least one spring-loaded locking device (60) for holding the safety platform (40) in a defined position, said spring-loaded locking device )60) being mounted to the safety platform (40).
The safety system according to claim 1, characterized in that the safety platform (40) comprises a platform frame (41) and a platform surface (42), said platform surface (42) being surrounded by said platform frame (41) or said platform surface being mounted on the platform frame, said platform surface (42) preferably being made from a lightweight material and/or being a net and/or being a mesh.
The safety system according to claim 1 or 2, characterized in that the elastic strands (50) are connected to the safety platform (40) at the edges thereof.
The safety system according to anyone of claims 1 to 3, characterized in that at least one of the elastic strands (50) is guided over a guidance device, in particular over a guidance reel (53), or that at least one of the elastic strands (50) is further connected to a guidance device, in particular to a guidance reel (53).
The safety system according to anyone of claims 1 to 4, characterized in and that the elastic strands (50) have the property of generating elastic restoring forces, in particular of generating progressive restoring forces.
The safety system according to anyone of claims 1 to 5, characterized in that the elastic strands (50) are made from an elastic material or are at least partially made from an elastic material, and that the elastic material is preferably selected from the group consisting of rubber, caoutchouc, latex.
The safety system according to anyone of claims 1 to 6, characterized in that the at least one spring-loaded locking device (60) laterally protrudes from the safety platform (40), in particular from the platform frame (41).
The safety system according to anyone one of claims 1 to 7, characterized in that the spring-loaded locking device (60) comprises a spring-loaded wheel (61).
The safety system according to claim 8, characterized in that the spring-loaded wheel (61) is mounted to a wheel base (62), said wheel base (62) being movably mounted in a receiving recess (63), said receiving recess (63) being assigned to the service platform (40), and that a spring member (64) is mounted inside the receiving recess (63), said spring member (64) interacting with the wheel base (62).
An underground refuse collecting apparatus (10), comprising a receiving pit (11), said receiving pit (11) comprising a pit side wall (12) and a pit opening (14) for receiving a refuse container (16), said apparatus (10) further comprising a refuse container (16) being movably arranged inside the receiving pit (11), and a safety system (40) for closing the pit opening (14), once the refuse container (16) has been removed from the receiving pit (11), characterized in that the safety system (30) is provided according to anyone of claims 1 to 9.
The underground refuse collecting apparatus according to claim 10, characterized in that the safety platform (40) of the safety system (30) is movably mounted inside the receiving pit (11) between a first ground position, in which the refuse container (16) is stored inside the receiving pit (11), and a second safety position in which the refuse container (16) is removed from the receiving pit (11) and in which the pit opening (14) is closed by the safety platform (40).
The underground refuse collecting apparatus according to claim 11, characterized in that the elastic strands (50) of the safety system (30) are provided such that they exert a maximum elastic restoring force, if the safety platform (40) is in the first ground position.
The underground refuse collecting apparatus according to anyone of claims 10 to 12, characterized in that the pit side wall (12) comprises an interaction device (70) for interacting with the spring-loaded locking device (60), in particular a spring-loaded wheel (61) thereof, said interacting device (70) preferably being capable of fixing the safety platform (40) in the second safety position.
The underground refuse collecting apparatus according to claim 13., characterized in that the interaction device (70) comprises a receiving profile element being mounted to the pit side wall (12), or a recess (71) being formed inside the pit side wall (12), or a projection (72) protruding from the pit side wall (12).
The underground refuse collecting apparatus according to anyone of claims 10 to 14, characterized in that it further comprises a chute device (19) being assigned to the refuse container (16) and being adapted for receiving refuse to be inserted into the refuse container (16), and/or a device (20) for removing the refuse container (16) out of the receiving pit (11) and for placing the refuse container (12) into of the receiving pit (11).