Thermal insulation means and combinations of screed and thermal insulation means

Abstract

To provide a road finishing machine in which heating of a screed for the road finishing machine is made more energy efficient and / or less time consuming.SOLUTION: Thermal insulation means 100 is provided for use with a screed 110 for a road finishing machine 120. The thermal insulation means comprises at least one thermal insulation element 101 and one connection element 113 for removable connection with the screed. The thermal insulation element is designed to reduce the radiation of heat from the screed through the thermal insulation element when the thermal insulation means is connected to the screed.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to heat insulation means connected to a screed for a road surface finishing machine according to claim 1, and a combination of a screed and heat insulation means according to claim 11.

Background Art

[0002] Screeds are well-known from the prior art. These are connectable to a road surface finishing machine and the material laid for road paving can be supplied via a material bunker. The screed can further heat the material and spread and compact it on a road formed corresponding to the working width of the screed.

[0003] In order to enable the operation of the screed, the screed usually first needs to be preheated to a working temperature necessary to reliably spread the material for spreading on the road at a sufficient temperature. However, the screed has a large surface, and thus, due to the thermally conductive material as a component of the screed, heat flow from the screed, particularly from the heating means of the screed, can reach the environment, which may delay the heating of the screed to the working temperature or at least make it energy-inefficient.

Summary of the Invention

Problems to be Solved by the Invention

[0004] Based on the known prior art, the technical objective to be achieved is to make the heating of the screed for a road surface finishing machine more energy-efficient and / or less time-consuming.

Means for Solving the Problems

[0005] According to the present invention, this objective is achieved by a heat insulating means used with a screed for a road finishing machine according to independent claim 1, and by a combination of a screed and a heat insulating means according to independent claim 11. Advantageous further developments of the present invention are contained in the dependent claims.

[0006] The thermal insulation means according to the present invention, used in conjunction with a screed for a road finishing machine, comprises at least one thermal insulation member and one connecting member for a detachable connection to the screed, wherein the thermal insulation member is designed to reduce heat radiation from the screed through the thermal insulation member when the thermal insulation means is connected to the screed.

[0007] Here, the state in which the insulating means is connected to the screed means that the insulating means is detachably connected to the screed by a connecting member, and therefore, the insulating member should be understood as being in a state in which it can perform its intended function of reducing heat radiation from the screed through the insulating member. This can also be understood as the "proper" position of the insulating means or at least the insulating member relative to the screed.

[0008] Here, the insulating members are preferably fastened to the screed from the outside by detachable connections, and thus they can at least partially cover the outer surface of the screed.

[0009] A detachable connection, in the sense of this disclosure, should be understood as a connection that can be formed and released without damaging any of the materials. Therefore, the connecting member is preferably designed to form a detachable connection with a corresponding connecting member of a screed by forming a friction connection or friction contact. For example, the connecting member can be configured as a plug or clamp that can engage with a corresponding element of a screed.

[0010] According to the present invention, physical contact between the insulating member and the screed is not essential when the insulating means is connected to the screed, but it is possible to provide it. It is only necessary to position the insulating member relative to the screed when the insulating means and the screed are connected, so as to reduce the amount of heat radiated from the screed through the insulating member during the heating process to the operating temperature or working temperature of the screed.

[0011] This reduces the radiation of heat to the environment during screed heating, thereby enabling rapid heating and / or heating with low energy consumption. Therefore, since less energy is required to achieve the required operating temperature, screed heating can be more advantageous not only from an environmental standpoint but also from an economic standpoint.

[0012] Once the screed has finished heating, the insulating device can be disconnected from the screed and the screed operation can be resumed. Alternatively, the insulating device can be left connected to the screed to reduce heat radiation to the environment during operation, for example.

[0013] Insulating means and / or at least one insulating member that can be located in or within the bottom or rising region of the screed can, in particular, have a high coefficient of static friction and / or a high coefficient of dynamic friction. In particular, the coefficient of static friction and / or dynamic friction of the insulating member can preferably be higher than the corresponding coefficient of the screed. For this purpose, the insulating member can be made of a material having such a coefficient of static friction and / or dynamic friction, or it can have an outer coating of such material on the surface opposite to the screed when connected to the screed. This makes it possible to achieve secure positioning of the screed in a structurally simple manner, in addition to improved heating. In particular, this anti-slip property of the insulating member or insulating means can be advantageously utilized to ensure the screed is securely positioned, for example, during transport by truck.

[0014] Furthermore, the insulating member may optionally have insulating material on the surface facing the screed or on the surface opposite to the screed when the insulating means is connected to the screed.

[0015] The insulating material can be incorporated into the insulating material itself, or it can be placed on the surface facing the screed or the opposite surface, so that heat conduction through the insulating material is reduced compared to heat conduction to the environment in the absence of the insulating material. The insulating material can preferably be designed as a “blanket” or “mat” that includes a surface facing the screed and the opposite surface, which together cover at least 80% or at least 90% of the entire surface of the insulating material when the insulating means is connected to the screed. A large surface parallel to the surface of the screed makes it possible to efficiently achieve a reduction in the amount of heat radiated to the environment by the screed.

[0016] Advantageously, the thermal insulation material may include or consist of one of rubber, polyurethane, or composite foam. These materials have a low coefficient of thermal conductivity so that the insulation of the screed is as efficient as possible. In principle, the embodiments described herein should not be understood as restrictive. Any of the materials or any combination of any of the materials may be used as a thermal insulation material having a preferred low coefficient of thermal conductivity relative to the material of the screed.

[0017] In one embodiment, the thermal insulation means comprises an active heating element for heating the screed, with the thermal insulation means connected to the screed. The active heating element should be understood as an element capable of substantially converting energy (e.g., electric current) into heat (preferably at least 90%) when energy is supplied, and radiating this heat. In this embodiment, the thermal insulation means can contribute additionally to heating the screed, thereby enabling the intended working temperature to be reached more quickly. Although energy is required for this, the time required to reach the working temperature is reduced, thereby making the operation of the screed more efficient.

[0018] In particular, the active heating element can be incorporated into the insulating member or positioned on the surface of the insulating member facing the screed while the insulating means is connected to the screed. In this embodiment, it is possible to simultaneously achieve a reduction in heat radiation from the screed to the environment via the insulating member, and additionally, efficient heating by the active heating element of the insulating means can be achieved, thereby shortening the time to reach at least the operating temperature of the screed.

[0019] The active heating element may also be equipped with an electric heating element, and the insulating means may be equipped with an accumulator which can be connected to the active heating element to supply current to the active heating element.

[0020] In this embodiment, the thermal insulation means requires no extensive maintenance and is widely applicable, making its use easily achievable, especially by a single construction worker.

[0021] In one embodiment, the insulating material can reduce the heat radiation from the screed through the insulating material by at least 25%, or at least 50%, or at least 75%. This reduction should be understood as being relative to the heat radiation from the screed to the environment in the absence of any insulating material. At least within the area of ​​the insulating material, heat loss during the heating of the screed is effectively reduced.

[0022] Furthermore, the connecting component can be designed as part of a security system that allows the screed heating process to be performed only when the screed is connected to the insulating means.

[0023] Therefore, the connecting member can perform a dual function: on the one hand, by assisting in the proper positioning and / or connection of the insulating means to the screed; and on the other hand, by forming an electrical contact that can, for example, emit a signal to the screed's control unit indicating that a connection has been formed. The control unit can then enable the heating of the screed. The initiation of the screed's operation, and in particular the initiation of the heating process, is therefore only possible if the insulating means is properly connected to the screed. This makes it possible to avoid unintended heating of the screed without insulating means, and thereby, energetically inefficient heating of the screed.

[0024] In one embodiment, the thermal insulation means comprises at least two thermal insulation members. Basically, the thermal insulation members can have the same design (e.g., in terms of shape and / or size and / or weight), but they can also differ in terms of shape and / or size and / or weight. Providing multiple thermal insulation members can be advantageous in facilitating the handling of the thermal insulation means even by a single operator.

[0025] In particular, each heat insulating member can have a weight of less than 20 kg, preferably less than 10 kg. Embodiments of heat insulating members having these maximum weights enable manual handling by one operator or one screed or operator of a road finisher, thereby improving the applicability of the heat insulating means.

[0026] According to the present invention, there is further provided a combination of a screed and heat insulating means according to any one of the above-described embodiments, wherein the heat insulating member is disposed at least on a part of the surface of the screed, and the screed includes heating means for heating the screed.

[0027] In this combination, efficient heating of the screed can be achieved.

[0028] The screed can also be provided with a security system that enables activation of the heating means only when the connecting member of the heat insulating means is connected to the security system of the screed. Implementation of an operation or heating of the screed by the heating means without the (properly positioned) heat insulating means is prevented in this embodiment, and thus inefficient heating of the screed is avoided.

[0029] In one embodiment, the heat insulating means includes at least two heat insulating members, and the heat insulating members together cover at least 50% of the surface of the screed. Thereby, it is possible to efficiently reduce heat loss during heating of the screed. Particularly preferably, in order to prevent heat from escaping, it is possible to cover the largest individual surface element of the screed with the heat insulating member of the heat insulating means.

Brief Description of the Drawings

[0030] [Figure 1] It is a schematic view of a screed of a road finisher and heat insulating means according to one embodiment connected thereto. [Figure 2A] Shows different embodiments of the heat insulating member and the heat insulating means. [Figure 2B] Different embodiments of thermal insulation members and thermal insulation means are shown. [Figure 2C] Different embodiments of thermal insulation members and thermal insulation means are shown. [Figure 2D] Different embodiments of thermal insulation members and thermal insulation means are shown. [Modes for carrying out the invention]

[0031] Figure 1 shows a schematic diagram of the screed 110 of the road finishing machine 120 and the heat insulating means 100 according to the embodiment, which is arranged relative to the screed 110.

[0032] As is known from the prior art, a screed 110 for road paving can typically include a heating means 112 and a screed plate 111 that is heated by the heating means 112 and capable of heating and compacting the road pavement beneath the screed plate. The screed 110 can be connected to a towing vehicle 120 or a “road finishing machine” by a connecting member 113. If the connecting member 113 is designed as a leveling cylinder, any unevenness in the road surface can be compensated for by the corresponding activation and starting of these leveling cylinders, for example, by a control system 180. The leveling cylinders can also be actively designed to at least partially follow the path of the subsoil during the finishing of the road pavement while ensuring the necessary compressive force of the road pavement.

[0033] Instead of a single heating element 112, multiple heating elements can form a heating element, which are distributed at different locations on the screed 110 to heat the screed plate. Basically, the heating element 112 can generate heat, for example, by an electric current, and radiate it onto the screed plate 111 to heat it.

[0034] It is also known from the prior art that the screed 110 must first undergo a heating phase in which the screed plate 111 (and optionally the entire screed 110) is heated to a required operating temperature. Only when this operating temperature is reached can the screed be used for finishing road pavement. During this heating phase, the screed plate 111 is heated using the screed heating means 112. Even after the operating temperature has been reached, the heating means 112 can continue to radiate heat to maintain a constant temperature of the screed plate.

[0035] During the heating phase, a relatively large amount of energy is required, and since the screed is usually made of or contains a highly thermally conductive material (e.g., steel), a considerable amount of heat flows from the screed to the environment, and therefore some of the heat radiated from the heating means is not ultimately used to heat the screed plate 11 or the screed, but is instead dissipated into the environment.

[0036] According to the present invention, a thermal insulation means 100 is provided which is detachably connectable to the screed 110, comprising at least one thermal insulation member 101, which is capable of reducing heat radiation from the screed to the environment, at least within the area of ​​the thermal insulation member, as long as the thermal insulation means is connected to the screed. For this purpose, the thermal insulation member 101 of the thermal insulation means 100 can be located, for example, below the screed 110 (meaning between the screed and the ground), as shown herein, so that the screed plate or other part of the screed heated by the heating means 112 radiates heat at least partially toward the thermal insulation member.

[0037] Due to the thermal insulation properties of the insulating material, heat transfer to the environment through the insulating material is prevented, or at least partially prevented, and therefore this heat can be used to heat the screed without being dissipated into the environment.

[0038] Embodiments of the thermal insulation means having only one thermal insulation member are not essential. The thermal insulation means 100 may also comprise two or more thermal insulation members 101, and in particular, the thermal insulation members may be positioned on other surfaces of the screed 110, thereby reducing or completely preventing heat flow from the screed to the environment through the thermal insulation members when the thermal insulation means and the screed are connected.

[0039] Preferably, the thermal insulation means 100 has a connecting member 102 for detachably connecting the thermal insulation means or at least one thermal insulation member 101 of the thermal insulation means to the screed 110. For example, the connecting member 102 can be implemented as a click connection, screw connection, clamp, or other detachable connecting member, thereby enabling the connecting member 102 to connect, for example, to a connecting member 103 of the corresponding screed 110 to form a detachable connection. Typically, this detachable connection can be implemented by friction contact and / or interlocking contact. Preferably, the connecting members 102 and 103 can be designed such that the connection between the connecting members 102 and 103 is only possible if the position of the thermal insulation means and / or thermal insulation member 101 on which the thermal insulation means and / or thermal insulation member is located is correct relative to the screed 110. This ensures that when the screed is operated, particularly when a heating process is performed, the thermal insulation member or thermal insulation member 101 performs its intended function and heat radiation through them is reduced.

[0040] The connecting member 102 of the heat insulation means 100 can also form part of a security system 131 that permits the execution of the heating process of the screed 110 (which means in particular the activation of the heating element 112) only when a connection is formed between the connecting member 102 of the heat insulation means 100 and the corresponding connecting member 103 of the screed 110. For this purpose, electrical or electronic contacts can be provided, for example, so that they are closed when the connecting members 102 and 103 are connected, allowing, for example, a control unit 180 to receive a corresponding signal and subsequently activate the heating element 112.

[0041] Figures 2A to 2D show various embodiments of the thermal insulation member of Figure 1, which can be provided as part of the thermal insulation means according to the present invention.

[0042] Although only one thermal insulation member is shown in both Figures 1 and 2A-2D, as previously described, the thermal insulation means 100 can be equipped with multiple thermal insulation members that can be positioned at various locations relative to the screed, thereby preventing or reducing heat radiation through them. Here, the thermal insulation members can preferably be designed to be handled by one operator or worker, for example, by one operator of the road finishing machine 120 to which the screed 110 is connected. In particular, each thermal insulation member can have a mass of less than 20 kg, preferably less than 10 kg. Especially in embodiments with a mass of less than 10 kg, it is possible to make it relatively easy for one person to handle.

[0043] Basically, independently of the embodiments described in detail with reference to Figures 2A to 2D, it is advantageous if, at least within the region relating to the thermal insulation member, the heat radiation mediated by the screed reduced by each thermal insulation member is at least 25%, preferably at least 50%, or at least 75%, compared to the heat radiation that would occur to the environment via the screed in the same region without any thermal insulation member.

[0044] In Figure 2A, a first embodiment of the thermal insulation member 201 is shown as consisting of two layers 211 and 212. For better understanding, the upper side of layer 211, which faces away from the lower layer 212, faces towards the screed or is in contact with the screed when the thermal insulation means is connected to the screed. This is assumed to mean that the bottom side of layer 212 (not shown in this figure), as the outer surface of the thermal insulation member, faces away from the screed when the thermal insulation means is connected to the screed.

[0045] Corresponding to the embodiment shown in Figure 2A, the upper layer 212 or at least the surface facing the screed direction may contain insulating material, or the lower layer 212 may contain insulating material (the surface of layer 212 facing away from the screed, in each case). Layer 211 or layer 212 or its surface may consist entirely of insulating material. Preferably, the insulating material may be, for example, rubber, polyurethane, or composite foam. Preferably, the insulating material used has a thermal conductivity of less than 0.5 W / (mK), preferably less than 0.3 W / (mK).

[0046] In Figure 2A, the thermal insulation member 201 is composed of two layers, one or both of which may contain their respective thermal insulation materials, and one of the two layers may be entirely made of thermal insulation material. Therefore, layer 211 can be considered, for example, as the "surface" of layer 212 and also made of thermal insulation material. Alternatively, layer 212 can be considered as being made of thermal insulation material and also forming the surface of layer 211.

[0047] Each of the other layers, which do not contain thermal insulation material, can act as a support layer to stabilize the thermal insulation member, and can, for example, have higher rigidity than the thermal insulation material. This makes handling easier.

[0048] The shapes of the insulating members shown in Figures 2B to 2D, not just Figure 2A, are not mandatory. The shape of the insulating member or insulating means can be basically any shape. However, the shape is preferably a rectangle or square, which is easy to handle, as it can be placed side by side without gaps to achieve complete and continuous screed abandonment.

[0049] Figure 2B shows an alternative embodiment to that in Figure 2A, where the thermal insulation material 222 in this embodiment is positioned between two layers 223 and 221, which can be made of other materials, and these three layers together form a thermal insulation member 202. Here, layers 221 and 223 can take over functions unrelated to heat conduction from the screed through the thermal insulation member 202, for example, they can serve as support layers for the thermal insulation material 222. Moreover, layer 221, positioned on the surface of the thermal insulation material 220 facing away from the screed when the thermal insulation means is connected to the screed, can be made of a material that reflects infrared rays or include a corresponding surface (e.g., aluminum foil). This can be positioned on the surface of layer 222 facing the direction of the thermal insulation material 222, and therefore, if heat transport is by infrared rays, the infrared rays are reflected and do not detach from the thermal insulation member 202 in the direction of the environment.

[0050] Although the embodiments in Figures 2A and 2B are described as multilayer systems, implementation using only a single material layer is also possible. For example, a single layer of insulating material can be provided as an insulating member. Preferably, this layer includes an infrared-reflecting material on the surface facing away from the screed, thereby preventing the emission of heat by infrared radiation.

[0051] Figure 2C shows a further embodiment of the thermal insulation member 203, wherein the thermal insulation member comprises an active heating element 233, which in the embodiments described herein can be designed to include, for example, a row of heating coils. Other embodiments are also conceivable. Preferably, the active heating element 233 is positioned on the surface of the thermal insulation member facing the screed in the connection state of the thermal insulation means and the screed (this can be understood here as the "upper side"). Here, the active heating element 233 can be positioned on the surface of the material layer 231, and particularly preferably on a further material layer 232 of the thermal insulation member 203, which includes, for example, a low thermal conductivity material. The material layer 231 can be particularly thermally conductive so that heat is transported from the active heating element 233 to the screed. The material layer 232 can be made of, or include, the above-mentioned thermal insulation material to prevent or reduce heat conduction in the direction opposite to the screed. Alternatively, or in addition, similar to Figure 2B, an infrared-reflective surface coating may be provided in or on layer 232 to reflect heat radiation in the direction of the screed (radiated from the screed in the opposite direction by the active heating element 233 in the connection state of the insulating means and the screed), thereby preferably fully utilizing the heat radiated from the active heating element 233 for heating the screed.

[0052] Furthermore, to supply current to the active heating element, the accumulator 234 can be associated with or connected to the connected active heating element. This accumulator 234 can be designed as, for example, a battery or a rechargeable battery or fuel cell, and can be connected to the active heating element 233 via a corresponding power supply line. Alternatively, instead of the accumulator, a connection to a (publicly available) power grid or a combustion engine, such as the combustion engine of a road finishing machine, can be provided.

[0053] Figure 2D shows a further embodiment in which the active heating element 243 is embedded in the material layer 241 and is not placed on the surface of the material layer 231 of the insulating member 203, as shown in Figure 2C. Preferably, by embedding it in a material layer 241 having good thermal conductivity (particularly better thermal conductivity than insulating material), it is possible to achieve, on the one hand, a uniform heat distribution of heat radiated by the active heating element 243 in the direction of the screed, and on the other hand, to protect the active heating element 243 from environmental influences (e.g., humidity). As in Figure 2C, a corresponding accumulator 244 can also be provided here.

[0054] The layer 242 of the thermal insulation member 204 in Figure 2D can be formed in the same way as the layer 232.

Claims

1. 1. An insulating means (100) for use with a screed (110) for a road finishing machine (120), said insulating means (100) comprising at least one insulating element (101) and one connecting element (102) for detachable connection to the screed (110), said insulating element (101) being designed to reduce radiation of heat from the screed (110) through said insulating element (101) when said insulating means (100) is connected to the screed (110).

2. 2. The insulating means (100) according to claim 1, wherein the insulating element (101) optionally comprises an insulating material (211, 212) on a surface facing the screed (110) or on a surface facing away from the screed (110) when the insulating means (100) is connected to the screed (110).

3. The thermal insulation means (100) of claim 2, wherein the insulating material (211, 212) comprises one of rubber, polyurethane, and composite foam.

4. The insulation means (100) according to any one of claims 1 to 3, wherein the insulation means (100) comprises an active heating element (233) for heating the screed (110) when the insulation means (100) is connected to the screed (110).

5. 5. The insulation means (100) of claim 4, wherein the active heating element (233) is integrated into the insulation member (204) or is arranged on the side of the insulation member (203) facing the screed (110) when the insulation means (100) is connected to the screed (110).

6. 5. The thermal insulation means (100) of claim 4, wherein the active heating element (233) comprises an electric heating element, and the thermal insulation means comprises an accumulator (234, 244) connected or connectable to the active heating element (233) for supplying current to the active heating element (233).

7. 2. The insulating means (100) according to claim 1, wherein the insulating element (211, 212) is capable of reducing the radiation of heat from the screed (110) through the insulating element (211, 212) by at least 25%, or at least 50%, or at least 75%.

8. 2. The insulation means (100) according to claim 1, wherein the connecting element (102) is designed as part of a security system (131) that allows the heating process of the screed (110) to be carried out only when the screed (110) is connected to the insulation means (100).

9. The thermal insulation means (100) of claim 1, wherein the thermal insulation means (100) comprises at least two thermal insulation members (101).

10. 2. The insulating means (101) according to claim 1, wherein each insulating element (101) weighs less than 20 kg, preferably less than 10 kg.

11. 1. A combination of a screed (110) and an insulating means (100) according to claim 1, wherein the insulating element (101) is arranged on at least a portion of the surface of the screed (110), and the screed is provided with heating means (112) for heating the screed (110).

12. 12. The combination according to claim 11, wherein the screed (110) comprises a security system (131) that allows activation of the heating means (112) only when the connecting member (102) of the insulation means is connected to the security system (131) of the screed (110).

13. 13. The combination according to claim 11 or 12, wherein the insulating means (100) comprises at least two insulating elements (101), which together cover at least 50% of the surface of the screed (110).

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