Balance with material box and load changing device

Abstract

The invention relates to a balance, comprising:-a magazine for test weights (100) to be sequentially weighed,-a weighing device having a weighing object carrier (200) for accommodating a respective test weight (100) during an associated weighing process; and-a load changing device for transferring each test weight (100) currently to be weighed from the magazine to the object-to-be-weighed carrier (200), the magazine comprising an electrically rotatable turntable (300), the test weights (100) being arranged in test weight receptacles that are rotatable together with the turntable (300) so as to be distributed over the periphery of the turntable (300), and by means of the turntable, the test weight accommodating parts for bearing the test weights (100) to be weighed currently can be positioned above the weighed object carrier (200) in the weighing preparation positioning. The invention is characterized in that each test weight receptacle is designed as a carrier pod (400) mounted thereon so as to be vertically movable relative to the turntable (300), which carrier pod can be height-adjusted relative to the turntable (300) by means of a first electric height adjustment unit (500, 500 ').

Description

Technical Field

[0001] The present invention relates to a balance, comprising:

[0002] - a bin for the test weights to be weighed successively,

[0003] - a weighing device having an object carrier for receiving a test weight in each case during an associated weighing process; and

[0004] - a load changer for transferring the test weight currently to be weighed from the magazine to the object carrier,

[0005] The material box includes a turntable that can be rotated electrically, and the test weights can be arranged in a test weight accommodating part that can rotate together with the turntable in a manner distributed on the periphery of the turntable, and with the help of the turntable, the test weight accommodating part carrying each test weight currently to be weighed can be positioned above the object carrier in the weighing preparation positioning. Background Art

[0006] Such a balance, in particular a mass comparator, is known from DE 10 2015 104 693 A1.

[0007] As so-called mass comparators, high-precision precision balances are known, which are specially designed to compare a weight block of a specific nominal weight, sometimes referred to as a test weight, with a corresponding mass standard, sometimes referred to as a reference weight. Test weights and reference weights should be summarized as the term test weights here without limiting the generality. Such mass comparators are particularly used for calibrating or adjusting weight blocks. Here, the test weights are usually stored in a material box and are transported to the actual weighing device, especially its weighed object carrier, in sequence by means of a load changing device. In this way, multiple test weights can be weighed in sequence automatically. The specific structure of the actual weighing device is irrelevant within the scope of this application.

[0008] A mass comparator is known from the above-mentioned literature according to the category, whose material box is constructed as a horizontally oriented turntable. On the upper side of the turntable, the test weights to be weighed can be positioned in turn at preset positions distributed on the periphery of the turntable. The turntable is rotatably supported on the front edge of a hollow cylindrical housing in the area of ​​its outer periphery by means of a plurality of rolling bearings. The actual weighing device with the upwardly oriented weighing object carrier is located inside the housing. In particular, the weighing object carrier is positioned so that each test weight holder can be accurately positioned above the turntable by the corresponding angular position of the turntable. The resulting angular position of the turntable or the corresponding test weight holder is referred to as the weighing preparation position. In the known mass comparator, in order to be able to transfer the test weight from its test weight holder to the weighed object carrier, the actual weighing device is arranged on a lifting platform, which can be moved upward in the housing so that the upwardly oriented protrusion of the weighed object carrier passes through the corresponding gap of the test weight holder just above the weighed object carrier, i.e. in its weighing preparation position, and the test weight can be removed from the test weight holder, so that its gravity now acts directly on the weighed object carrier. After the weighing process, the weighing device is lowered again by means of the lifting platform, so that the test weight is transferred back to the test weight holder. The descent of the weighing device is carried out in this case so that the protrusion of the weighed object carrier is completely released from the gap of the test weight holder. Then, the turntable can be rotated further until the other test weight holder and the test weight arranged thereon are just positioned above the weighed object carrier, i.e. in its weighing preparation position. The above-mentioned process can be repeated with a new test weight.

[0009] It is understood by those skilled in the art that within the scope of this specification, terms such as "up" and "down" refer to the ready-to-run orientation of the balance, i.e. towards the direction of gravity; therefore, in this sense, terms such as "raise" and "lower" should be understood as movement upward or downward.

[0010] A disadvantage of the known mass comparators is that the actual weighing device is arranged on a movable element, namely the lifting table, which can lead to (slight) instabilities. To solve this problem, the cited document provides for moving the lifting table toward a vertical stop, thereby solving the mentioned problem to a large extent, although not completely. In addition, the mechanism of the lifting table may require the use of lubricants, so that the known system is not suitable for vacuum.

[0011] An alternative concept of a mass comparator is known from EP 3 255 393 A1, in which the actual weighing device is fixed on a base plate and the turntable can be adjusted vertically and rotationally relative to the base plate. This has the disadvantage that the axis of the turntable must perform two different movement components. These movement components are therefore coupled to one another and their bearing clearances interact, so that the control with the extremely high precision required for the mass comparator is structurally very demanding and therefore expensive. Here, too, the disadvantageous use of lubricants is necessary.

[0012] A device for transporting test weights from a magazine configured as a rotatable carrying ring to a load holder of a lower pan balance is known from DE 10 2005 005 366 A1. The carrying ring has a plurality of positions for accommodating test weights. Below each position there is a slit-shaped through-opening, and beside each position there is a hole in the first carrying ring, the diameter of which is greater than the diameter of the test weight. In order to transfer the test weight from the carrying ring to the load holder (which is configured as a bracket surrounding the carrying ring), the carrying ring is rotated until the test weight stops above the placement surface of the load holder. Then, the bolt of the lifting device located below the load holder raises the test weight by passing the through-opening in the placement surface of the load holder and the slit-shaped through-opening in the carrying ring. Then, the carrying ring is rotated until the adjacent holes in the carrying ring are located above the placement surface of the load holder and are therefore located below the test weight. Then, the lifting device lowers the test weight onto the load holder by retracting its bolt. Summary of the invention

[0013] The object of the present invention is to improve a universal balance, in particular a universal mass comparator, such that a system is produced which is also suitable for vacuum applications while maintaining the decoupling of the vertical and rotational movement components and while achieving the highest possible positioning accuracy.

[0014] This object is achieved in conjunction with the features of the preamble of claim 1 in that each test weight receptacle is constructed as a carrier pod supported on the turntable in a manner that allows vertical movement relative to the turntable, and the carrier pod can be adjusted in height relative to the turntable by means of a first electric height adjustment unit.

[0015] The basic idea of ​​the present invention is that, for the height adjustment of the test weight (which is necessary within the scope of transferring the test weight to the weighing object carrier), each individual test weight holder is designed to be electrically vertically adjustable, rather than the entire material box or the actual weighing device. In other words, the individual vertical mobility of each individual test weight holder relative to the turntable and the weighing object carrier is achieved. Therefore, the turntable itself does not have to perform vertical movement, so that its support and its drive can be designed only for its rotational movement component. For the turntable itself, each vertical movement component can be completely blocked. At the same time, there is no need to raise or lower the actual weighing device. Therefore, it can be fixed on the base in any stable manner. Since each rough movement mechanism is abandoned, it is also not necessary to use lubricants, so that the resulting balance can provide vacuum in principle.

[0016] Preferably, each carrier pod is preloaded upwardly toward the stopper fixed to the corresponding rotating disk, and can be electrically lowered downwardly in the opposite direction of the spring preload force by the force applied by the first electric height adjustment unit. Here, the spring force of the preload spring should exceed the weight of the carrier pod and the test weight positioned thereon in the operating state. Thus, the highest position that the carrier pod can occupy is precisely defined by the stopper mentioned. This position of the carrier pod can be referred to as the rest position. Each carrier pod is first in its rest position. This is also particularly applicable to the carrier pod and the test weight currently to be weighed that are positioned above the weighed object carrier in its weighing preparation positioning by the rotation of the rotating disk. Now it is necessary to lower the carrier pod downwardly from this rest position so that the test weight is transferred to the weighed object carrier. This descent is electrically realized by the first electric height adjustment unit. Within the scope of actual load transfer, the interaction between the test weight receiving portion, the test weight and the weighed object carrier can follow known principles. It is therefore preferably provided that the bottom of the carrier pod is provided with a slot, through which the corresponding projection of the weighed object carrier passes when the carrier pod is in its weighing preparation position in the lowered state. When the carrier pod is lowered, the projection of the weighed object carrier moves under the bottom of the test weight and removes the test weight from its test weight receptacle, i.e. from the bottom of the carrier pod. After the weighing process, the force effect of the first electric height adjustment unit is turned off or at least reduced to a certain extent, so that the carrier pod is raised again by the spring force of the preload spring and transferred back to its rest position.

[0017] The specific mechanism of the vertical movement of the carrier pod can be realized in different ways. The following embodiment is considered to be particularly advantageous, in which the carrier pod is hinged on the turntable by means of a parallel link assembly (its fixed end is fixed on the turntable and its movable end is fixed on the carrier pod). For the skilled technicians in weighing technology, the parallel link assembly is known in detail, and the parallel link assembly is also used as a rack mechanism in the so-called weighing system. The parallel link assembly is basically composed of a horizontal upper link, a lower link extending parallel to it, and a rigid coupling column that connects the ends of the two links to each other in pairs. Unlike a simple bending column, when the parallel link assembly is deflected, the spatial orientation of the coupling column on the movable end is accurately maintained during the (slightly bent) vertical movement of the coupling column. The upper link and the lower link can be rigidly constructed and hinged on the coupling column. In this case, it is possible to construct the parallel link assembly as an integral unit and design the joint as a material thin point. Alternatively, the upper link and the lower link can be configured as leaf springs rigidly fixed on the coupling column. In any case, there is no sliding contact surface with friction, as is the case when the carrier pod is supported on a vertical guide rod or toothed rod.

[0018] The parallel rod assembly is preferably adjusted so that in the rest position, i.e., in particular when resting against the above-mentioned stop, the upper and lower rods are slightly deflected upwards from their exact horizontal position. This exact horizontal position should preferably be achieved in the lowering phase, during which the test weight is actually transferred from the carrier pod to the weighed object carrier. Therefore, in this phase, the error introduced by the circular movement of the movable coupling column is minimal: here, the horizontal movement component approaches zero.

[0019] The most advantageous variant for realizing this embodiment of the invention in terms of construction space is the articulation of the carrier pod suspended below the turntable. In this arrangement, the fixed end of each parallel rod assembly is fixed to the underside of the turntable. Of course, other designs are also possible with corresponding additional expenditure on construction space and mechanical devices. However, for the sake of simplicity, the subsequent description will focus on the above-mentioned design with a suspended carrier pod, wherein the person skilled in the art can also easily transfer the corresponding embodiments to other variants.

[0020] In principle, it is conceivable that each carrier pod is equipped with its own electric drive. The electric drive is located between the free end of the carrier pod or the parallel rod assembly and the turntable and is mechanically connected to these two elements. However, this may have adverse effects in terms of heat. On each electric drive, heat is generated during its operation. However, the temperature stability of the system is very important for high-precision weight measurement. Therefore, in this embodiment, the heat input must be compensated in some way thermodynamically or mathematically. On the contrary, a more advantageous and preferred embodiment is provided that the first electric height adjustment unit is not mechanically connected to the turntable. Therefore, the turntable can be rotated relative to the first electric height adjustment unit, and each test weight receiving portion is individually delivered to the first electric height adjustment unit. Then, the first electric height adjustment unit can be designed so that it can only act on each carrier pod that is positioned in the weighing preparation position.

[0021] In particular, it can be provided that the first electric height adjustment unit has an eccentric cam fastened to an electrically rotatable camshaft, wherein the cam is arranged such that a tappet connected in a vertical force-transmitting manner to the respective carrier pod in the position ready for weighing is located within the range of motion of the cam, so that the tappet can be mechanically pressed down by means of the cam by rotation of the camshaft. The motor driving the camshaft can be arranged outside the thermally insulated and optionally evacuated central region of the entire system. As a result, no heat is generated in the region of the test weight or the actual weighing device by its operation. Instead, only a mechanically interacting pair of cam and tappet is located in this critical central region, wherein the tappet is fastened to the carrier pod itself or to the parallel rod assembly.

[0022] In particular, in the variant explained above as preferred with a suspended carrier pod, it can be provided that the camshaft extends above the turntable parallel to the turntable and out of plane with respect to its axis of rotation, the carrier pod is suspended below the turntable, and the respective tappet of the carrier pod projects into or through the respectively associated recess of the turntable. In this embodiment, the mechanical interaction between the first electric height adjustment unit and the carrier pod (in its weighing preparation position), in particular between the cam and the tappet, is realized through the turntable. In particular, the first electric height adjustment unit can be arranged in a largely free area above the turntable, as opposed to below the turntable where the carrier pod is arranged, where sufficient installation space is available.

[0023] The turntable is preferably axially supported on a plurality of rolling bearings distributed over its circumference and acting upward on its underside. It is particularly advantageous if the turntable is axially supported by means of exactly three rolling bearings. The rolling bearings are loaded with the weight of the entire magazine, which results in a very stable support in the vertical or axial direction. The preferred selection of exactly three rolling bearings for the axial support of the turntable results from the associated precise determination of the turntable plane.

[0024] With regard to the radial support of the turntable, it is preferably provided that the turntable is radially supported by means of a plurality of rolling bearings distributed over its circumference and acting radially inwards on its circumferential surface. It is preferably provided here that the turntable is radially supported by means of exactly three rolling bearings, two of which are designed as fixed bearings and one of which is designed as a spring-prestressed floating bearing. Thus, even in the case of (small) wear, a precise support is always ensured and thus a consistently reproducible rotational movement of the turntable is ensured.

[0025] In order to drive the turntable, it is preferably provided that the turntable can be driven by means of a friction wheel that rolls on its surface and can be driven electrically. The advantage of a friction wheel drive is the maximum torque that is limited by the slipping of the friction wheel on the turntable surface, which ensures a higher accident safety unlike a meshing drive (e.g. a toothed belt or gear drive). However, such a drive and, for example, a friction belt drive within the scope of the present invention are also usable in principle. At least due to slipping, it is considered advantageous that the turntable is equipped with a rotational attitude indicator. This allows high reproducibility of transferring each test weight receptacle to a position ready for weighing. In a non-slip drive variant, this reproducibility can be ensured only by precise motor control if necessary.

[0026] In a preferred embodiment of the friction wheel drive, the friction wheel rolls on the upper side of the turntable and is fixed on an electrically rotatable drive shaft arranged on the turntable and perpendicular to its axis of rotation. Unlike the rolling of the friction wheel on the peripheral surface or the lower side of the turntable, in this preferred design, the pressure applied by the friction wheel to the turntable cannot interfere with the support of the turntable that is also arranged there. However, the rolling of the friction wheel on the peripheral surface provides a saving potential, so that one of the radial bearings of the turntable, especially the floating bearing, can be constructed as a roller bearing and perform a corresponding dual function. The motor driving the drive shaft itself can be arranged outside the central area of ​​the entire system, especially outside the heat insulation core. As explained above in the text of the camshaft, undesirable heat input into the central area of ​​the system is avoided.

[0027] The function of the carrier pod is explained above only in the text of transferring the test weight to the weighed object carrier. However, the same principle can also be used to equip the carrier pod with test weights from an external test weight reserve, or to use when emptying the material box into the mentioned external test weight reserve. Firstly, it is provided that an equipment unit is arranged at an angle staggered with respect to the rotation axis of the turntable and the weighed object carrier, and by means of the equipment unit, the material box can be equipped with a weight block from the weight block reserve as a test weight. Advantageously, the carrier pod descending mechanism is designed dually for this purpose. In other words, it is preferably provided that in addition to the first electric height adjustment unit, a similar second electric height adjustment unit is also provided, which can only act on the carrier pod in the carrier pod that is currently located in the equipment preparation position above the conveying element of the equipment unit that can move radially relative to the turntable. On the equipment unit, the vertical position of the carrier pod then interacts with the test weight transporter that can move radially (with respect to the turntable). In order to load, the empty carrier pod is first rotated into the mentioned equipment preparation position. Subsequently, the carrier pod descends. The conveying element equipped with the test weight moves radially inward from the test weight reserve and positions the test weight above the bottom of the carrier pod. The carrier pod is then raised again and takes over the test weight, wherein the gap in the bottom of the carrier pod also interacts with the projection of the conveying element without collision. Subsequently, the conveying element is moved radially outward again, and the next carrier pod is moved to the equipment preparation position by the rotation of the turntable. In order to unload the carrier pod, the interaction with the conveying element is carried out in the opposite way, in particular (except for the radial movement) similar to transferring the test weight to the weighed object carrier, as described above. Of course, it is also possible to combine the unloading and loading of the carrier pod in a single process of replacing the test weight in the described carrier pod. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Further details and advantages of the present invention are obtained from the following detailed description and drawings.

[0029] Figure 1 A perspective view showing an embodiment of a load changer for a balance according to the invention,

[0030] Figure 2 A schematic diagram showing the load replacement principle according to the present invention is shown,

[0031] Figure 3 A schematic diagram showing a preferred embodiment of a height adjustment unit according to the present invention is shown.

[0032] Figure 4 shows a schematic top view of an embodiment of a turntable of a balance according to the invention,

[0033] Figure 5shows a schematic cross-sectional view of an embodiment of a turntable of a balance according to the invention,

[0034] Figure 6 A perspective view showing an embodiment of a weighing object carrier of a balance according to the present invention is shown,

[0035] Figure 7 A perspective view showing an embodiment of the load-bearing bottom of the carrier pod of the balance according to the invention, and

[0036] Figure 8 A schematic diagram showing the process of equipping a carrier pod of an embodiment of a balance according to the invention is shown.

[0037] The same reference numbers in the drawings identify the same or similar elements. DETAILED DESCRIPTION

[0038] Figure 1 A preferred embodiment of a load changer 10 for a balance according to the invention is shown in a perspective view. The load changer 10 shown is not combined with a Figure 1 Not shown, but in Figure 2 and Figure 3 The function of the magazine for test weights 100 shown in FIG. 1 and the transfer of the respective test weight 100 currently to be weighed from the magazine to the actual weighing device (not shown in FIG. 1 ), in particular the mass comparator, are described in detail in FIG. Figure 1 Not shown, but in Figure 6 The actual function of the load changing device on the object carrier 200 is shown in FIG. Figure 1 The load changer 10 is described in the context of FIG. 1 , wherein reference is made to the remaining figures for the description of its individual elements.

[0039] The basic design element of the functional unit "box" is a turntable 300. The turntable 300 rotates about a central vertically oriented axis of rotation 301 (see Figure 2 ) is rotatably supported in a horizontal turntable plane. Figure 4 and Figure 5 As can be seen, its radial support is preferably carried out by means of radial rolling bearings 310 acting on its circumferential surface. A particularly preferred embodiment of this support is Figure 4 Here, exactly three radial rolling bearings 310 are used, of which two are designed as fixed bearings 311 and one is designed as a spring-preloaded floating bearing 312. The turntable 300 is axially supported by means of axial rolling bearings 320 acting on its underside, such as, in particular, from Figure 5 In a manner not shown, similar to the radial rolling bearing 310, Figure 4As can be seen in the distribution in FIG. 3 , the axial rolling bearings 320 are evenly distributed over the circumference of the turntable 300 , wherein preferably exactly three axial rolling bearings 320 are used.

[0040] like Figure 5 As shown, the rotation drive of the turntable 300 is preferably realized by means of a friction wheel 330 rolling on the upper side of the turntable 300, and the friction wheel can be driven by a drive shaft 331 of a motor not shown. Figure 1 As shown, the drive shaft 331 preferably extends above the turntable 300 and perpendicularly to its axis of rotation 301. The drive shaft 331 can be designed to be almost any length, so that the associated motor can be located far outside the load changer 10 in order to avoid any heat input caused by the motor into the "core" of the balance according to the invention.

[0041] The above-mentioned design scheme of the support and drive of the rotating disk 300 allows its annular disk design. This design in turn allows the weighing object carrier 200 to be Figure 2 The eccentric arrangement shown in the figure, for this purpose, the weighed object carrier can preferably be Figure 6 The design shown is assumed to be a cage. In the embodiment shown, the cage of the weighed object carrier 200 includes multiple, especially three vertical rods 210, which are interconnected to form the mentioned cage by an upper star 211 and a lower star 212. In the case of the lower dish design of the actual weighing device, the weighed object carrier 200 can be hinged on the load container of the weighing system in the center of its upper star 211. In the case of the upper dish design of the actual weighing device, the coupling of the weighed object carrier 200 with the load container of the weighing system is carried out in the central area of ​​the lower star 212. In any case, a test weight adapter 220 is arranged in the central area of ​​the lower star 212, and the test weight 100 to be weighed should be positioned on the test weight adapter for the weighing process. In the embodiment shown, the test weight adapter 220 is basically composed of an adapter plate 221, and three radially oriented and mutually angularly staggered 120° protrusions 222 protrude from the adapter plate. The function of protrusion 222 should be discussed in further detail below.

[0042] On the lower side of the turntable 300, a plurality of individually height-adjustable carrier pods 400 are arranged distributed around its periphery. The carrier pods have a carrier bottom 410 corresponding in shape to the test weight adapter 220. Figure 7 A perspective view of a preferred embodiment of the load-bearing bottom is shown. Figure 2 and Figure 3 As can be seen in FIG. 4 , each test weight 100 is placed on a load-bearing bottom 410. As can be seen in particular from Figure 7As can be seen, the support base 410 is provided with slots 411 therethrough, which slots are adapted in shape and orientation to the projections 222 of the test weight adapter 220 of the weighing object carrier 200. This will be discussed in further detail below.

[0043] First, with the help of Figure 2 The basic principle of a load changer 10 with a carrier pod 400 that can be individually adjusted in height shall be described. By appropriate rotation of the turntable 300, the selected carrier pod 400 and the test weight 100 positioned on its carrying base 410 can be moved into its weighing preparation position, in which the carrier pod is located above the test weight adapter 220 of the weighed object carrier 200. The person skilled in the art will understand that if it is mentioned in the present description that the test weight or the carrier pod is arranged "above the weighed object carrier", this relative positioning description only relates to the area of ​​the weighed object carrier for directly accommodating the test weight, i.e., in the embodiment shown, its weighed object adapter 220. It should not be contradicted that other areas of the weighed object carrier 200, in particular the upper star 211, can be arranged higher than the test weight or the carrier pod in the embodiment shown. In the embodiment shown, the carrier base 410 of the carrier pod 400 with the test weight 100 currently to be weighed is located in its weighing preparation position in the holder of the object carrier 200 above the test weight adapter 220 of the object carrier. Figure 2 . In this weighing preparation position, the carrier pod 410 can be lowered relative to the turntable 300 (including all other carrier pods 400) and relative to the weighed object carrier 200 by means of the height adjustment unit 500, 500'. During the descent, the gap 411 of the carrier bottom 410 is penetrated by the test weight adapter 220, in particular its protrusion 222. When the carrier pod 400 is lowered deep enough, the test weight 100 is transferred from the carrier bottom 410 to the test weight adapter 220, so that the weight of the test weight 100 is now only loaded on the weighed object carrier 200, so that the weighing process can be performed by means of the actual weighing device. Figure 2 The height adjustment unit 500' in FIG. 4 is shown purely schematically as a small motor unit, each carrier pod 400 having its own motor unit. However, this does not correspond to a preferred embodiment of the invention. Figure 1 is shown in perspective and in Figure 3 It is shown very schematically in FIG.

[0044] As from Figure 3As can be seen, in a preferred embodiment of the height adjustment unit 500, the carrier pod 400 is articulated on the lower side of the turntable 300 by means of a parallel linkage assembly 510. The parallel linkage assembly 510 comprises a first coupling column 511 fixed to the turntable 300 and a second coupling column 512 fixed to the carrier pod 400, which are connected to each other by means of an upper link 513 and a lower link 514 parallel to the upper link. The links 513, 514 are connected to the coupling columns 511, 512 in an articulated manner, wherein preferably a joint with a thin point of material constructed as an integral part is used. Alternatively, the links 513, 514 can be constructed as leaf springs rigidly connected to the coupling columns 511, 512. By means of a preload spring 515, shown here as a helical spring, the parallel linkage assembly 510, in particular its second coupling column 512, is spring-preloaded upward with the carrier pod 400, wherein the stop 340 on the turntable provides an exact definition of the maximum raised position of the parallel linkage assembly 510 or the carrier pod 400. The tappet 520, which is rigidly connected to the second coupling column 512, extends into the notch 350 of the turntable 300 or passes through it completely. In any case, the tappet 520 provides an action surface for the forces acting vertically thereon, by means of which the parallel linkage assembly 500 is deflected against the spring force of the preload spring 515 and the carrier pod 400 can thereby be lowered. In the embodiment shown, the mentioned vertical force is applied by a cam 530 fixed to a camshaft 531. In the embodiment shown, the cam 530 is designed as a wheel eccentrically fixed to the camshaft 531. Of course, non-rotationally symmetrical cam shapes are also conceivable. As can be seen in particular from Figure 1 As can be seen, the camshaft 531 preferably extends parallel to the turntable plane and is eccentric with respect to its axis of rotation 301. It extends in particular parallel to the drive shaft 331 of the turntable drive. As described above in the context of the drive shaft, in conjunction with the camshaft 531 it is also possible to shift the motor driving the camshaft radially outwards in order to avoid a corresponding heat input into the "core" of the balance according to the invention.

[0045] In the embodiment shown, the second height adjustment unit 600 is arranged opposite the first height adjustment unit 500 (with respect to the rotation axis of the turntable 300 ). The second height adjustment unit operates exactly like the first height adjustment unit 500 , so that no new description is required here. Figure 1 The cam 630 and the camshaft 631 can be seen in FIG. The background of the dual implementation scheme is that Figure 1 The illustrated embodiment allows not only automated lowering of the carrier pod 400 for transferring the test weights 100 to the weighed object carrier 500, but also automated loading of the carrier pod 400 with test weights 100 from a test weight reservoir, not shown.

[0046] This equipment process Figure 8 In combination with the test weight storage, a conveying element 700 is arranged, which is designed here as a conveying tongue and can be moved linearly and in particular radially relative to the turntable. The tip of the conveying element 700 is provided with a radial projection 701 and a semicircular projection 702, which project upward from the plane of the tongue and serve as the actual placement of the test weight 100. In order to equip the carrier pod 400, as Figure 8 As shown in b, the test weight 100 is placed on the mentioned protrusions 701, 702. Then, the carrier pod 400 can be equipped in its ready-to-equip position, i.e. with its tappet exactly under the cam 630, Figure 8 b and Figure 8 Only the bearing bottom 410 of the carrier pod is shown in c. Figure 6 and Figure 7 As described in the text of the invention, the carrier bottom 410 of the carrier pod 400 has gaps 411, and when the carrier pod is lowered into its weighing preparation position, the corresponding protrusions 222 of the test weight adapter 220 of the weighed object carrier 200 will pass through these gaps. These gaps 411 or protrusions 222 are Figure 6 and Figure 7 However, the bearing bottom 410 also has an additional gap 412, which is ineffective in transferring the test weight to the object carrier 200. Figure 8 Additional gaps are required within the scope of the arrangement shown for the transfer of the test weights. When the carrier pod 400 is lowered, the conveyor element 700 loaded with the test weight 100 is positioned relative to its support base 410 in such a way that the tongue plane of the conveyor element, from which the projections 701 , 702 of the conveyor element project, is below the underside of the support base 410 of the carrier pod 400, wherein, however, the upper edges of the projections 701 , 704 are above the upper side of the support base 410. In this relative position, as shown by Figure 8 As shown by the white arrow in b, the conveying element moves linearly onto the carrier pod 400, wherein the linear protrusion 701 of the conveying element moves into the additional gap 412 of the carrier bottom 410, thereby generating Figure 8 c. The carrier pod 400 can be raised again from this position and in the process take over the test weight 100 from the conveyor element 700 .

[0047] Of course, the embodiments discussed in the specific description and shown in the drawings represent only illustrative embodiments of the present invention. Based on this disclosure, a person skilled in the art will be given a wide range of variation possibilities.

[0048] Reference numerals list

[0049] 10 Load changer

[0050] 100 Test Weights

[0051] 200 Object carrier

[0052] 210 Vertical Rod

[0053] 211 Upper star

[0054] 212 Lower star

[0055] 220 Test Weight Adapter

[0056] 221 Adapter Plate

[0057] 222 Bump

[0058] 300 Turntable

[0059] 301 Rotation axis

[0060] 310 Radial rolling bearings

[0061] 311 Fixed bearing

[0062] 312 Floating bearing

[0063] 320 Axial rolling bearings

[0064] 330 Friction Wheel

[0065] 331 Drive shaft

[0066] 340 Stopper

[0067] 350 Gap

[0068] 400 Carrier Pod

[0069] 410 Load-bearing bottom

[0070] 411 Gap

[0071] 412 Gap

[0072] 500 Height adjustment unit

[0073] 500' Height Adjustment Unit

[0074] 510 Parallel Link Assembly

[0075] 511 Coupling column

[0076] 512 Coupling column

[0077] 513 Upper connecting rod

[0078] 514 Lower Link

[0079] 515 Preload Spring

[0080] 520 Tappet

[0081] 530 Cam

[0082] 531 Camshaft

[0083] 600 Height adjustment unit

[0084] 630 Cam

[0085] 631 Camshaft

[0086] 700 Conveyor elements

[0087] 701 Bump

[0088] 702 Bump

Claims

1. A balance, comprising: - a bin for the test weights (100) to be weighed successively, - a weighing device having a weighing object carrier (200) for receiving a respective test weight (100) during an associated weighing process; and - a load replacement device, the load replacement device being used to transfer each test weight (100) currently to be weighed from the material box to the weighed object carrier (200), The material box comprises a rotating disk (300) that can rotate electrically, the test weights (100) can be arranged in a test weight receiving portion that can rotate together with the rotating disk (300) in a manner distributed on the periphery of the rotating disk, and the test weight receiving portion that carries each test weight (100) to be weighed can be positioned above the weighed object carrier (200) in the weighing preparation positioning by means of the rotating disk, The invention is characterized in that each test weight receiving portion is constructed as a carrier pod (400) supported on the turntable in a manner that it can move vertically relative to the turntable (300), and the carrier pod can be adjusted in height relative to the turntable (300) by means of a first electric height adjustment unit (500, 500').

2. The balance according to claim 1, It is characterized in that Each carrier pod (400) is spring-preloaded upward toward an associated stop (340) fixed relative to the turntable, and can be electrically lowered downward in opposition to the spring preload force by means of a force applied by the first electric height adjustment unit (500, 500').

3. A balance according to any one of the preceding claims, It is characterized in that Each carrier pod (400) is hinged to the turntable (300) by means of a parallel link assembly (510), wherein the fixed end of the parallel link assembly is fixed to the turntable (300) and the movable end of the parallel link assembly is fixed to the carrier pod (400).

4. A balance according to any one of the preceding claims, It is characterized in that The first electric height adjustment unit (500) is mechanically unconnected to the turntable (300) and can only act on each carrier pod (400) that is in the weighing preparation position.

5. According to claim 4, the balance according to claim 3, It is characterized in that The first electric height adjustment unit (500) has an eccentric cam (530) fixed on an electrically rotatable camshaft (531), wherein the cam (530) is arranged so that a push rod (520) connected to each carrier pod (400) in the weighing preparation position in a vertical force transmission manner is located within the movement range of the cam (500), so that the push rod (520) can be mechanically pressed down by the cam (530) through the rotation of the camshaft (531).

6. The balance according to claim 5, It is characterized in that The camshaft (531) extends on the rotating disk (300) parallel to the rotating disk and eccentrically relative to the rotation axis of the rotating disk. The support pods (400) are supported in a suspended manner below the turntable (300), and the respective rams (520) of the support pods extend into or through the respectively associated recesses (350) of the turntable (300).

7. A balance according to any one of the preceding claims, It is characterized in that The rotary disk (300) is axially supported on a plurality of, in particular exactly three, rolling bearings (320) distributed over its circumference and acting upwardly on its underside.

8. A balance according to any one of the preceding claims, It is characterized in that The rotating disk (300) is radially supported by means of a plurality of rolling bearings (310; 311, 312) distributed on its circumference and acting radially inwards on its circumferential surface.

9. The balance according to claim 8, It is characterized in that The turntable (300) is radially supported by means of exactly three rolling bearings (310), two of which are designed as fixed bearings (312) and one of which is designed as a spring-prestressed floating bearing (311).

10. A balance according to any one of the preceding claims, It is characterized in that The rotating disk (300) can be driven by means of an electrically drivable friction wheel (330) which rolls on its surface.

11. The balance according to claim 10, It is characterized in that The friction wheel (330) rolls on the upper side of the rotating disk (300) and is fixed on an electrically rotatable drive shaft (331) which is arranged on the rotating disk (300) and perpendicular to the rotation axis (301) thereof.

12. A balance according to any one of the preceding claims, It is characterized in that The bearing bottom (410) of the carrier pod (400) is provided with a gap (411), and when the carrier pod is in a descending state in its weighing preparation position, the corresponding protrusion (222) of the weighed object carrier (200) passes through the gap.

13. A balance according to any one of the preceding claims, It is characterized in that An equipment unit is arranged at an angle offset with respect to the rotation axis (301) of the turntable (300) and the object carrier (200), and by means of the equipment unit, the material box can be equipped with a weight block from a weight block storage device as a test weight (100).

14. According to claim 13, the balance according to claim 4, It is characterized in that In addition to the first electric height adjustment unit (500, 500'), a similar second electric height adjustment unit (600) is also provided, which can only act on the carrier pod (400) that is currently located in the equipment preparation position above the conveying element (700) of the equipment unit that can move radially relative to the turntable (300).

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