PRECISION PENDULUM LOAD SUPPORT

Description

[0001] The invention relates to a so-called pendulum load support, which is used particularly in industrial weighing technology in platform or container scales. Various designs are known from the prior art, as described, for example, in documents FR2709181A3, DE 102016118046 B4, EP 0 315 846 B1, US 4 815 547, or DE 196 25 821 C1.

[0002] Pendulum load supports have the function of shielding lateral forces from load cells, so that only the forces caused by the mass of the material to be weighed act on the load cells.

[0003] There are various requirements in industrial weighing technology, such as the special requirements for hygienic conditions in the food industry. Here, the production systems in which the trolleys are integrated must be cleaned and disinfected frequently. This is done, for example, with steam or hot water sprayed under pressure onto the system components. The steam or water also contains disinfectants. All components of the production system must be designed to be easy to clean. There must be no gaps or cavities that are inaccessible during cleaning, as these could harbor bacterial cultures, which must be prevented in the food industry. Accordingly, a pendulum load support must also be able to be safely cleaned. Conventionally designed pendulum load supports do not meet these requirements.

[0004] The document DE 102016118046 B4 describes a pendulum load support which, according to the inventors, is suitable for use in the food industry.

[0005] In the pharmaceutical industry, however, the requirements for sterility are sometimes even higher. Furthermore, higher demands are generally placed on dosing accuracy, meaning that the respective pharmaceutical components must sometimes be weighed or dosed with greater precision than in the food industry.

[0006] Pendulum load supports utilize point and / or linear supports as bearing components to minimize frictional resistance. It is known that the phenomenon of Hertzian pressure occurs at the contact points, i.e., a flattening of the contacting components. The extent of this flattening depends, among other things, on the force with which the components are pressed together.

[0007] From the state of the art in weighing technology, it is known how the contact points of such bearing components are to be constructed and which materials are preferably suitable for this purpose.

[0008] Mechanical precision weighing technology requires components with a particularly small linear, ring-shaped, or point-shaped contact area. However, this results in very high surface pressure, and the contacting material surfaces are subjected to heavy loads and wear. Mechanical precision scales are even designed for the so-called pan and the cutting edge moving within it to be replaceable. This design effort is not possible with a pendulum support used in industrial scale construction. It must therefore be expected that the mobility of a pendulum load support will decrease over time, especially if moisture and possibly aggressive cleaning and disinfection agents come into contact with the bearing surfaces. Another problem is that downtime is undesirable in some production plants, and therefore the moving components of the pendulum load support must have the longest possible service life.

[0009] It is therefore the object of the invention to provide a pendulum load support with a long service life that retains its mobility throughout its entire service life, even in high humidity and under the influence of aggressive cleaning and disinfection agents.

[0010] The problem is solved with a pendulum load support according to claim 1.

[0011] The pendulum load support has the following features: A base plate, preferably made of stainless steel, in which a concentric cylindrical recess with a flat bottom surface is provided, a pendulum bolt with a ball-shaped underside and a spherical top surface and a pendulum piece with a cylindrical recess whose diameter is larger than the diameter of the upper section of the pendulum bolt. A depression is provided centrally in the bottom surface of this cylindrical recess. The ball-shaped underside of the pendulum bolt rests on the flat bottom surface of the recess. The pendulum piece rests with its central depression on the spherical top surface of the pendulum bolt. A bell-shaped cover made of an elastic plastic is hermetically sealed to the pendulum piece at its upper edge section and hermetically sealed to the base plate at its lower edge section.

[0012] The bell shape of the cover has various advantages: Depending on requirements, materials with different elasticity and temperature resistance and other desired properties can be used. A free space containing air or a special gas is formed beneath the cover. The volume of gas or air is greater than the sum of the volumes of the sections of the pendulum bolt and the pendulum piece that are enclosed by the air or gas. This ensures that the enclosed gas can circulate easily and the moisture it contains remains constant at all points. This largely prevents condensation of moisture due to temperature changes in specific areas, and condensed moisture evaporates quickly. This is advantageous because it means that the lubricants used retain their lubricating properties for longer.

[0013] According to claim 2, the cover is made of an antibacterial plastic, which has particular advantages when used in the food and pharmaceutical industries.

[0014] According to claim 3, as an alternative to the subject matter of claim 2, only the outer surface of the cover is provided with an antibacterial coating.

[0015] According to claim 4, the cover consists of at least two layers of material. Two or more layers of material increase the flexibility of the cover. The cover becomes more flexible and thus does not distort the forces resulting from the masses to be weighed. The outer layer of the cover can be made of a material with antibacterial properties.

[0016] According to claim 5, a hygroscopic substance is embedded within the air or gas filling, which keeps the humidity of the gas low. This ensures long-lasting effectiveness of the lubricants.

[0017] According to claim 6, the gas filling is an inert gas. This also ensures long-lasting effectiveness of the lubricants.

[0018] The invention is explained in more detail below with reference to schematic drawings: Fig. 1 shows a pendulum load support in a perspective view, Fig. 2 shows the pendulum load support in cross section, Fig. 3 shows a pendulum load support in cross section in a second embodiment, Fig. 4 shows a pendulum load support in cross section in a third embodiment, Fig. 5 shows a pendulum load support in cross section in a fourth embodiment and Fig. 6 shows the installed pendulum load support during cleaning and disinfection. List of reference symbols

[0019] 1 Base plate 2 Cylindrical recess in the base plate 3 Flat bottom surface of the cylindrical recess 4 Pendulum bolt 5 Ball-shaped underside of the pendulum bolt 6 Spherical top side of the pendulum bolt 7 Pendulum piece 8 Cylindrical recess in the pendulum piece 9 Conical depression in the pendulum piece 10 Bell-shaped cover 11 Air or gas filling 12 Antibacterial coating 13 Hygroscopic material 14 Cleaning device

[0020] The Fig. 1 shows a pendulum load support in a perspective view. The Fig. 2shows the pendulum load support in cross-section. The pendulum load support has the following features: a base plate 1 made of stainless steel, on the upper side of which a cylindrical recess 2 with a flat base surface 3 is provided concentrically, a pendulum bolt 4 with a ball-shaped underside 5 and a spherical upper side 6, a pendulum piece 7 with a cylindrical recess 8 whose diameter is larger than the diameter of the upper section of the pendulum bolt 4, and a centrally inserted conical depression 9. The lower section of the pendulum bolt 4 is inserted into the cylindrical recess 2 of the base plate 1 and the pendulum piece 7 rests on the spherical upper side of the pendulum bolt 4.

[0021] A bell-shaped cover 10 made of an elastic plastic is hermetically sealed to the pendulum piece 7 at its upper edge and hermetically sealed to the base plate 1 at its lower edge. The connection at the upper edge is preferably adhesive, but if necessary, it can also be clamped. The connection to the base plate is preferably detachable, e.g., clamped by screwing. The space beneath the cover 10 is filled with air or gas 11.

[0022] For the pendulum load support according to Fig. 3 Only the outer surface of the cover 10 has an antibacterial coating 12. This has the advantage that the cover can be made of a particularly flexible and gas-tight plastic and still have an antibacterial effect.

[0023] For the pendulum load support according to Figure 4The cover 10 consists of six layers of material. This arrangement has several advantages. For example, the outer layer of material can be thin yet resistant to aggressive cleaning agents. The inner layers are made of a particularly soft, elastic material. The individual layers are not bonded to one another.

[0024] For the pendulum load support according to Figure 5 A hygroscopic substance 13 is embedded in the air or gas filling 11. This ensures long-lasting effectiveness of the lubricants.

[0025] The Figure 6 shows an installation situation in which the pendulum load support installed in a system is cleaned by means of a steam jet 14.

Claims

1. Pendulum load support, comprising the following features: - a base plate (1), in which a cylindrical recess (2) with a flat bottom surface (3) is concentrically formed, - a pendulum pin (4) with a ball-shaped bottom side (5) and a spherical upper side (6), - a pendulum piece (7) with a cylindrical recess (8) whose diameter is greater than the diameter of the upper section of the pendulum pin (4), and a centrally provided cavity (9), wherein the pendulum pin (4) is pivotably mounted in the cylindrical recess (2) via its ball-shaped bottom side (5) and pivotably supports the pendulum piece (7) via its spherical upper side (6), - a bell-shaped cover (10) made of elastic plastic, which is connected to the pendulum piece (7) at its upper edge section in a hermetically sealed manner and which is connected to the base plate (1) at its lower edge section in a hermetically sealed manner, so that a space is formed which contains an air or gas filling (11), whereby the following condition is fulfilled: the volume of gas or air (11) is greater than the sum of the volumes of the sections of the pendulum pin and the pendulum piece that are enclosed by the air or gas.

2. Pendulum load support according to claim 1, wherein the cover (10) is made of an antibacterial plastic.

3. Pendulum load support according to claim 1, wherein the cover (10) comprises an antibacterial coating (12).

4. Pendulum load support according to claim 1, wherein the cover (10) consists of at least two plastic layers.

5. Pendulum load support according to claim 1, wherein a hygroscopic substance (13) is stored in the air or gas filling (11).

6. Pendulum load support according to claim 1, wherein the gas filling (11) is an inert gas..