Weighing apparatus and weight magazine therefor

Abstract

The invention relates to a weighing apparatus (10), comprising - a weighing sensor, a load carrier (122) and a weighing system coupling the load carrier (122) to the weighing sensor, - a weight magazine (14) with a plurality of weights (28) stored therein and - a transfer device by means of which the weights (28) can be placed on the load carrier (122) as required. The invention is characterized in that the weight magazine (14) is designed as a magazine housing (141) with a magazine door (142) pivotably mounted thereon, on the inside of which the weights (28) are held and by means of which said magazine housing (141) can be closed, wherein the magazine door (142) forms a horizontally elongated weight support which is pivotable about a vertical pivot axis over the load carrier (122) and on which the weights (28) are held so as to be linearly displaceable together in the elongation direction of the weight support and individually vertically linearly displaceable between a weight storage position and a weight weighing position.

Description

[0001] Weighing device and weight magazine for it

[0002] Description

[0003] Field of the invention

[0004] The invention relates to a weighing device comprising

[0005] - a weighing sensor, a load carrier and a weighing system coupling the load carrier to the weighing sensor,

[0006] - a weight magazine with a plurality of weights stored therein and

[0007] - a transfer device by means of which the weights can be placed on the weighing carrier as required.

[0008] The invention further relates to a weight magazine comprising a plurality of jointly horizontally movable weight pieces.

[0009] Finally, the invention relates to a weight magazine comprising a plurality of jointly horizontally movable weight bearings.

[0010] State of the art

[0011] Such a weighing device and such a weight magazine are known from DE 103 00625 B3.

[0012] The weighing devices according to the invention serve to automate weighing processes in which the weight values ​​of different weights are determined one after the other. For this purpose, such weighing devices comprise an actual scale for carrying out the actual weighing process, a weight magazine for storing the weights to be weighed, and a transfer device by means of which the weights can be fed one after the other to the scale or the weighing process. The actual scale essentially consists of a weighing sensor, which in modern laboratory balances typically operates according to the principle of electromagnetic compensation, a weighing object carrier, for example a weighing pan, for holding the weights to be weighed during the weighing process, and a lever mechanism, referred to here as the weighing system, which couples the weighing object carrier to the weighing sensor in a displacement-transmitting or force-transmitting manner.Such scales are well known and are offered for different purposes in different configurations and with varying degrees of precision. The present invention primarily relates to so-called laboratory scales, but can also be used with other types of scales.

[0013] DE 102015 104693 A1 discloses a so-called comparator, i.e., a scale specifically designed to compare nominally identical weights with very high precision. Such comparators are used, for example, to check calibration weights that are subsequently used to calibrate scales of lower precision classes, such as laboratory balances. For both cost-effectiveness and the reproducibility of such precision measurements, automation of the weighing process is desirable. This ensures that the weights to be weighed are exchanged quickly and, at the same time, positioned precisely on the weighing load carrier—typically exactly centered to avoid so-called off-center load errors.To this end, the aforementioned publication proposes designing the weight magazine as a horizontally aligned turntable arranged above the scale, on which the weights are positioned distributed around its circumference. Each weight rests on a weight bearing, which in the previously known design is designed like a grate. The weighing object carrier of the scale has vertically aligned projections corresponding to the grate. The scale as a whole is mounted on a vertically movable lifting table. To transfer a weight to the scale, the turntable is rotated until the weight currently being weighed is positioned exactly centrally above the weighing object carrier.The scale is then raised until the vertically aligned projections of your weighing object carrier penetrate the grate-like weight bearing from below and lift the weight from the turntable so that its weight force acts directly on the weighing object carrier and is transmitted to the weighing sensor via the weighing system.

[0014] A similar comparator is known from US 6,784,380 B2, where the scale stands on a fixed base, whereas the turntable is lowered during the transfer process.

[0015] From the aforementioned generic document DE 103 00 625 B3, a transfer mechanism for weights between a scale and an adjacent weight magazine is known. A horizontally and vertically movable handling device is arranged between the scale and the magazine, on which a swivel arm with self-centering weight holders is mounted. The free end of the swivel arm is fork-shaped and corresponds to the grids that serve as the scale's load carrier and the magazine's weight holders.

[0016] From DE 20 2005 017255 U1 a transfer mechanism designed as a portal conveyor between a scale and a weight magazine adjacent to it is known.

[0017] From WO 2011 / 138140 A1, the transfer of weights between a scale and an adjacent weight magazine by means of a multi-axis robot arm is known.

[0018] These transfer mechanism concepts are not very practical for laboratory balances. For example, laboratory balances typically feature a draft shield, the walls of which define a weighing chamber that completely surrounds the load-carrying unit. Therefore, transferring weights from a weight magazine located above or to the side of the weighing chamber is impossible. Within the weighing chamber, even if one wanted to store the weights there, there is typically not enough space for the known transfer mechanisms, as the weighing chamber walls typically enclose the load-carrying unit quite tightly without unnecessary waste of space. In addition, complex mechanisms are difficult to clean, which precludes their arrangement within the weighing chamber. Nevertheless, a mechanism for automatically transferring different weights from a weight magazine to the load-carrying unit would also be desirable for laboratory balances, particularly for carrying out calibration processes.Such calibration processes must be routinely repeated at specified intervals to ensure that the laboratory balance operates within the specified tolerances, or to adjust the internal calibration and correction parameters of the control system. For this purpose, different calibration weights—that is, weights that are traceable to weights of higher precision classes—must be weighed according to a specified calibration protocol in order to compare the actual weighing result with the nominal values ​​of the calibration weights. Such a calibration process is time-consuming and, if performed manually, requires specially trained personnel.This requires not only precise adherence to the calibration protocol, including sufficient acclimatization of the calibration weights and precise centered positioning on the weighing load carrier; proper handling of the sensitive calibration weights, which require special protection, is also important.

[0019] DE 102018 106617 A1 discloses a special calibration weight arrangement consisting of the actual calibration weight (weight) and a housing in which the calibration weight, designed as a standardized knob weight consisting of a head, neck, and body, is suspended from a collar. The interior of the housing is designed such that the suspended calibration weight is completely mechanically released from the housing when lifted vertically relative to the housing. In particular, the knob weight hangs with its thickened head from the collar, the diameter of which is smaller than the head diameter and larger than the neck diameter, and the thickness of which is dimensioned less than the height of the constriction defined as the neck between the head and the body of the calibration weight.If such a calibration weight arrangement is placed centrally over the load carrier of a laboratory balance, the base of the weight comes into contact with the surface of the load carrier before the lower edge of the downwardly open housing on the balance base comes into contact around the load carrier. As the housing is lowered further, the calibration weight is raised relative to it. As soon as the calibration weight no longer has mechanical contact with its housing, its weight acts directly on the load carrier, allowing it to be weighed precisely. With a suitable centering aid, such a calibration weight arrangement can therefore help solve the problems of precisely centering the calibration weight and, at the same time, protecting it during manually performed calibration processes. However, the aforementioned publication does not provide an approach for the aforementioned, desirable automation of the calibration process.

[0020] Task

[0021] The object of the present invention is to further develop a generic weighing device in such a way that it can be configured as a laboratory balance. A further object of the invention is to further develop a generic weight magazine in such a way that it can be used to automate the calibration of laboratory balances.

[0022] Description of the invention

[0023] The above-mentioned first object is achieved in conjunction with the features of the preamble of claim 1 in that the weight magazine is designed as a magazine housing with a pivotally mounted magazine door, on the inside of which the weights are held and by means of which said magazine housing can be closed, wherein the magazine door forms a horizontally elongated weight carrier which can be pivoted about a vertical pivot axis above the weighing item carrier, on which weight carrier the weights are held in a manner which can be jointly moved linearly in the longitudinal direction of the weight carrier and individually displaced vertically linearly between a weight storage position and a weight weighing position.

[0024] The above-mentioned second object is achieved with the features of claim 17, namely by a weight magazine comprising a magazine door, a magazine housing and a plurality of jointly horizontally movable weights, wherein the weights are held on the inside of the magazine door, which is mounted pivotably about a vertical pivot axis on the magazine housing which can be closed by means of said magazine door, wherein the joint horizontal mobility of the weights is linear in nature and the weights are also individually displaceable vertically linearly between a weight storage position and a weight weighing position.

[0025] The above-mentioned object is achieved with the features of claim 18, namely by a weight magazine comprising a magazine door, a magazine housing and a plurality of jointly horizontally movable weight bearings, wherein the weight bearings are designed as individual suspensions, by means of which weights shaped as button weights can be held on the inside of the magazine door, which is mounted pivotably about a vertical pivot axis on the magazine housing which can be closed by means of said magazine door, wherein the joint horizontal mobility of the weight bearings is linear in nature and the individual suspensions and the weights, if present, can be displaced vertically linearly between a weight storage position and a weight weighing position by means of the weights held thereon.

[0026] Preferred embodiments are the subject of the dependent claims.

[0027] According to the invention, a swivel arm is used as the essential element of the weight magazine instead of a turntable. This swivel arm has a main extension direction in the horizontal and is mounted so that it can pivot about the vertical. Similar to a crane boom, it can thus sweep a circular sector around the swivel axis. This sweepable circular sector comprises at least one position – preferably the approximately central position – above the weighing sample carrier and a position outside the weighing sample carrier. The former will be referred to below as the weighing swivel position, the latter as the rest swivel position. In the particularly preferred case in which the swivel axis is located in the region of a corner of the weighing chamber of a laboratory balance, the pivotable weight carrier can thus be pivoted between its rest swivel position, in which it is approximately parallel to a weighing chamber wall, and a weighing swivel position, in which it projects approximately centrally above the weighing sample carrier.According to the invention, the weights are mounted on the swivel arm or weight carrier in such a way that they can be moved linearly together along the arm's extension. In this way, when the weight carrier or swivel arm is in its weighing swivel position, each of the weights can be positioned exactly above the center of the weighing item carrier by moving all of the weights a correspondingly wide distance together along the arm's extension. Furthermore, the invention provides that each of the weights—at least when it is in the previously described position centered above the weighing item carrier—can be individually lowered vertically onto the weighing item carrier.The horizontal rotation and vertical linear movement of the entire weight magazine known from the prior art is thus replaced in the invention by the combination of a pivoting movement of the weight carrier with a common horizontal linear movement of the weights and additionally a vertical linear movement of each individual weight.

[0028] As previously mentioned, such a weight carrier can be stored in a very space-saving manner within the weighing chamber of a laboratory balance, so that in its resting, swiveling position it does not interfere with the daily operation of the laboratory balance, but can be used during calibration processes to place the weights one after the other onto the weighing sample carrier according to a predefined calibration protocol. Together with an advantageous motorization of the individual movements, explained in more detail below, and suitable control of the motors, the calibration process can be automated. In particular, with suitable control, the calibration process can start automatically at times when the laboratory balance is not needed for normal laboratory operation, for example, during nighttime laboratory downtime. Sufficient time can also be planned for the calibration weights held on the weight carrier in the weighing chamber to acclimatize.The latter applies especially in cases where the weight carrier is brought into the weighing chamber specifically for calibration purposes and is pivotably mounted there. However, in cases where the laboratory balance is permanently equipped with a weight carrier according to the invention, along with the calibration weights attached to it, the need for separate acclimatization is eliminated.

[0029] Furthermore, the invention provides that the weight carrier is designed as a

[0030] A magazine door is formed which, together with a magazine housing on which it is pivotally mounted and which can be closed by means of said magazine door, forms the weight magazine, and on the inside of which the weights are held. This protects the sensitive calibration weights inside a closed magazine housing. Such a weight magazine can be arranged in direct contact with the weighing chamber surrounding the weighing sample carrier. In this way, the magazine door, which functions as the weight carrier according to the invention, can be pivoted into the weighing chamber and, in particular, over the weighing sample carrier.

[0031] It is possible for such a weight magazine to be permanently integrated into the laboratory balance, in particular its weighing chamber. For example, the weight magazine can be integrated into the weighing chamber wall or fixed to it. Alternatively, however, it can also be provided that the weight magazine is reversibly fixed in or on a weighing chamber wall, with an electrical and / or electronic interface of the weight magazine contacting a corresponding interface of the weighing chamber wall. In other words, in this embodiment, the weight magazine is designed as a module that can be inserted into the laboratory balance as needed. The energy and control supply required to control the motors (to be described in more detail below) for the individual movements explained above is provided via corresponding interfaces on the weight magazine module on the one hand and the weighing chamber wall on the other.Such interfaces can, for example, be designed as plug-socket systems, which can also be designed for the precise positioning of the module within the weighing chamber.

[0032] With regard to the motorization of the weight carrier according to the invention, i.e. the magazine door, it can be provided that this can be pivoted by means of a pivot motor, wherein it can be temporarily fixed in its weighing pivot position, in which each of the weights can be positioned centrally above the weighing item carrier by horizontal linear movement. The temporary fixability is advantageous in order to be able to reliably maintain the weighing pivot position during the lowering process of the weight currently to be weighed. Several variants are conceivable for the technical implementation. A predominantly mechanical solution consists in the magazine housing having a mechanical stop against which the magazine door can be pressed by a motor in the weighing pivot position. The weighing pivot position thus corresponds to a maximum opening of the magazine door. Alternatively, the pivot motor can be designed as a stepper motor.This controls the weighing swivel position by rotating the rotor of the stepper motor by a precisely specified number of angular steps. Another alternative to this is a predominantly electronic solution for equipping the swivel motor with a rotary encoder. As is known to those skilled in the art, such motors can be freely programmed so that they can move to and hold a specified angular position with great precision. A magazine door that can be swiveled using a stepper motor or a swivel motor with a rotary encoder can, if necessary, also be opened wider than the weighing swivel position. This is advantageous if the calibration weights stored in the weight magazine occasionally need to be replaced, for example, for regular inspections. In this case, opening the magazine door wide facilitates access to the weights stored there.

[0033] The weights are advantageously suspended from individual suspension points on a rigid, motor-driven weight housing that is open at the bottom and movable in the longitudinal direction of the magazine door. In other words, a rigid weight housing is provided that encloses all of the weights. This weight housing can be moved as a whole on the weight carrier, i.e., on the magazine door, thus ensuring the joint horizontal linear movement of the weights. Furthermore, such a weight housing offers an easy-to-handle unit that protects the calibration weight set it contains and can be easily replaced, along with the calibration weights, if necessary. If, for example, an inspection of the calibration weights by an external, certified body is required, the entire weight housing, including the calibration weights, can be sent in and temporarily replaced with an identical weight housing.If the weight housing is closed with the exception of its mandatory open bottom, the entire process can take place without unauthorized persons gaining direct access to the sensitive weights.

[0034] Within the weight housing, each individual weight is assigned an individual suspension. Each of these individual suspensions is advantageously linearly movable vertically within the weight housing between a lower stop and an upper stop. The stops define a range within which the respective weight, together with its individual suspension, can be moved vertically. It is considered particularly advantageous if each individual suspension is spring-loaded against its upper stop. This means that the individual suspension, or the weight suspended from it, is lowered into the weight weighing position by applying a lowering force counter to the spring force. The technical implementation of this principle will be explained in more detail below.However, as soon as the lowering force is removed, the spring preload pushes the individual suspension back against its upper stop into the weight storage position and the weight suspended from it is raised accordingly.

[0035] It is advantageous if each weight is suspended in its individual suspension in such a way that it loses all mechanical contact with the weight housing (including the individual suspension itself) when lifted relative to the individual suspension. If the base of the weight strikes the surface of the load carrier when the individual suspension is lowered, while the individual suspension is lowered further, this corresponds to a relative lifting of the weight, which thereby loses all contact with the weight housing. It rests exclusively on the load carrier, so its weight force acts entirely on it. In this state, precise weight determination using the weighing sensor is possible.

[0036] In terms of structural design, such an individual suspension can be advantageously realized by designing the weight as a rotationally symmetrical knob weight with a head of a first diameter, a cylindrical body of a second diameter, and a neck of a third diameter arranged between the head and the body, which is smaller than the first and second diameters. Each individual suspension has a cavity that is open at the bottom and surrounds the head of the associated weight with radial and axial oversize. The cavity is delimited at the bottom by a radially inwardly projecting collar with a clear width of a fourth diameter that is smaller than the first diameter and larger than the third diameter. Such a design is particularly advantageous since calibration weights are often designed as standard knob weights in accordance with OIML R 111-1: 2004 / DIN 8127: 2007-11.Such a knob weight hangs with its head on the collar, the thickness of which is less than the clear height of the constriction between the head and the body of the knob weight. Therefore, when the weight is slightly lifted relative to the collar, it is completely released from its individual suspension. The transfer of the weight from the weight housing to the weighing object carrier can thus be carried out in the manner described above.

[0037] In a favorable development of this embodiment, the cavity additionally has a lateral opening in the form of a flat channel extending transversely to the direction of travel of the weight housing, the clear channel profile of which is larger than the head profile of the associated weight and the underside of which is provided with a slot running through its longitudinal direction, the width of which is greater than the third diameter. This channel can preferably be designed to slope radially outwards. Such a channel allows the weights to be inserted laterally into the individual suspensions configured in this way. The head of the weight is inserted into the open, radially outer end of the channel, with its neck protruding through the slot on the underside of the channel. The body of the button weight is located below the channel.In this way, the knob weight can be slid along the channel to its end position in the individual suspension. In versions with a sloped channel, the knob weight automatically slides to its end position and remains there.

[0038] As already explained above, the weight housing as a whole can be moved horizontally and linearly. In particular, it is preferably provided that the weight housing is motor-driven and can be moved into various weight housing weighing positions, the number of which corresponds to the number of weights and in each of which one of the weights, which then acts as the currently weighable weight, is positioned centrally above the weighing item carrier, provided that the weight carrier, i.e. the magazine door, is simultaneously in its weighing swivel position. These weight housing weighing positions can be reached very precisely and reproducibly, especially with motors with a linear encoder. However, other implementation options for the required positioning of the weight housing are also known to the person skilled in the art. To lower the weights onto the weighing item carrier, it is preferred thatA motor-driven plunger is mounted on the magazine door, by means of which the individual suspension on which the currently weighable weight is suspended can be depressed. Such a motor-driven plunger can be implemented particularly easily, particularly in the designs described above with spring-loaded individual suspensions. For example, a bolt driven by a worm drive can be used, which is arranged above the weight housing at exactly the point on the weight carrier or the magazine door that is positioned exactly centrally above the weighing item carrier in the weighing swivel position. After the weight housing has been transferred to its weight housing weighing position, the individual suspension of the currently weighable weight is located exactly below the plunger and centrally above the weighing item carrier.When the plunger is lowered by motor, the individual suspension is moved downwards against the spring preload. After a certain lowering distance, the base of the currently weighed weight contacts the weighing object carrier. The weight is then in its weight weighing position. Further advance of the plunger leads to a further lowering of the individual suspension and the release of the weight, which then stands freely on the weighing object carrier and can be weighed. After the weighing process, the plunger is moved back to its starting position, with the spring preload lifting the individual suspension again and pressing it against its upper stop. The weight is then lifted onto and off the weighing object carrier and returned to its weight storage position.As soon as the plunger has been retracted far enough that it is no longer in contact with the individual suspension, the weight housing can be moved to a new weight housing weighing position in which a different weight acts as the currently weighable weight.

[0039] In this way, a complex calibration program can be run automatically. Those skilled in the art will understand that this naturally requires suitable control of the weighing sensor and suitable treatment and storage of measured values, which must be coordinated with the purely mechanical movement of the weights. The details of this depend heavily on the specific calibration program and are not the subject of the present invention. Following calibration, the weight carrier, i.e. the magazine door, can be pivoted away from the weighing item carrier and, in particular, the housing-like weight magazine can be closed, so that the weight magazine can either be removed as a whole or, if it is permanently integrated into the laboratory balance, does not impede further operation of the laboratory balance.

[0040] Further details and advantages of the invention will become apparent from the following specific description and drawings.

[0041] Brief description of the drawings

[0042] They show:

[0043] Figure 1: a roughly schematic representation of a preferred embodiment of a weighing device according to the invention in the form of a laboratory balance,

[0044] Figure 2: the laboratory balance of Figure 1 with the weight magazine removed,

[0045] Figure 3: a preferred embodiment of an inventive

[0046] Weight magazine with swing-open magazine door,

[0047] Figure 4: the weight magazine of Figure 3 in rear view with closed

[0048] magazine door,

[0049] Figure 5: the magazine door of the weight magazine of Figure 3 in weighing

[0050] Swivel position with the weight housing in weight housing retraction position,

[0051] Figure 6 : the magazine door of Figure 5 with the weight housing in a

[0052] Weight housing weighing position with the currently weighable weight in weight storage position,

[0053] Figure 7 : the magazine door of Figure 6 with the currently weighable weight in

[0054] Weight weighing position, Figure 8 : three detailed drawings of a weight and its

[0055] Individual suspension in different phases of the vertical linear lowering process as well as

[0056] Figure 9 : two detailed drawings of a preferred embodiment of a

[0057] Single suspension.

[0058] Detailed description of preferred embodiments

[0059] The same reference symbols in the figures indicate the same or analogous elements.

[0060] Figure 1 shows a roughly schematic representation of a weighing device 10 according to the invention, designed as a laboratory balance. This comprises an actual balance 12, of which only a balance base 121, a weighing sample carrier 122, and the weighing chamber walls 123 delimiting the weighing chamber around the weighing sample carrier 122 are shown. Not shown separately are the weighing sensor and the weighing system that couples the weighing sample carrier 122 to the weighing sensor. These elements, which are not shown, are concealed in the balance base 121. Typically, this is a weighing sensor operating according to the principle of electromagnetic compensation with a corresponding weighing system. However, the specific design of this sensor system is irrelevant to the present invention.

[0061] A weight magazine 14 according to the invention is arranged in the weighing chamber, particularly in the angle between the weighing chamber rear wall and the weighing chamber floor. It is essentially constructed of a magazine housing 141 and a magazine door 142. The magazine door 142 is shown with solid lines in a closed state, referred to here as the rest pivot position, and with dashed lines in an open state, referred to here as the weighing pivot position. In the weighing pivot position, the magazine door 142 protrudes approximately centrally over the weighing sample carrier 122.

[0062] Figure 2 shows the same weighing device 10 with the weight magazine 14 removed. In the illustrated embodiment, the weight magazine 14 is designed as a module that can be reversibly positioned in the weighing chamber. In other embodiments, the weight magazine 14 can also be permanently installed adjacent to the weighing chamber. In the illustrated module variant, the weight magazine 14 has an electrical and / or electronic interface 144 on its base, which, when inserted (Figure 1), contacts a corresponding interface 124 on the weighing chamber floor. The weight magazine 14 can be supplied with electrical power and control signals via this interface pair 124 / 144.

[0063] Figures 3 and 4 show a particularly preferred embodiment of a modular weight magazine 14. The weight magazine 14 is depicted in Figures 3 and 4 without a rear wall opposite the magazine door 142. This serves, on the one hand, to improve the clarity of illustration. On the other hand, actual embodiments without such a rear wall are also conceivable. In these, the weight magazine 14 is fixed, for example, with a suitable locking mechanism to a rear weighing chamber wall 123, which then simultaneously forms the rear wall of the weighing magazine 14. However, embodiments with a closed magazine rear wall are also conceivable.

[0064] Figure 3 shows a perspective view of the weight magazine 14 with the magazine door 142 in the weighing pivot position. Figure 4 shows the same weight magazine 14 with the magazine door 142 closed, viewed from behind through the open rear wall. Figures 5 to 7 show the magazine door 142 in isolation in its weighing pivot position. These figures will be described jointly below unless explicitly referenced to a specific figure.

[0065] The magazine door 142 is pivotally connected to the magazine housing 141 and is provided with a housing-mounted pivot motor 16, which is only shown in Figures 3 and 4. The pivot motor allows the magazine door 142 to be pivoted open and closed by a motor, with the motor and its control system being designed such that precise pivot positions of the magazine door 142 can be approached and maintained, in particular the weighing pivot position shown in Figures 5 to 7, which will be discussed in more detail below.

[0066] A horizontally oriented rail 18 is fixed to the magazine door 142, on which a weight housing 20 is mounted for linear displacement. The weight housing 20 is connected via a spindle drive 22 to a sliding motor 24 fixed to the door, allowing it to be moved along the rail extension by motor. The sliding motor 24 and its control system are preferably designed such that the weight housing 20 can be moved precisely and, in particular, into various weight housing weighing positions, one of which is illustrated in Figures 6 and 7.

[0067] In the illustrated embodiment, the weight housing 20 comprises a rigid shell having three separately vertically linearly movable individual suspensions 26 for weights 28. The specific design of the individual suspensions 26 will be discussed in more detail below in the context of Figures 8 and 9.

[0068] At a position of the magazine door 141, another motor, the ram motor 30, is fixed, which is coupled to a ram 32, for example, via a worm drive not shown in detail. The ram 32 is thus vertically movable by motor.

[0069] By actuating the displacement motor 24, the weight housing 26 can be moved such that each of the individual suspensions 26 is positioned precisely below the plunger 32. The plunger 32 is positioned relative to the magazine door 142 such that, in the swivel weighing position of the magazine door 142 shown in Figures 5 to 7, it is located exactly centrally above the weighing load carrier 122.

[0070] Figure 5 shows a weight housing retraction position, in which the weight housing is moved as far as possible on the pivot bearing side of the magazine door 142 to relieve the load on the pivot bearing. Figure 6, however, shows the weight housing 20 in one of three weight housing weighing positions, in which, in particular, the largest of the weights 28 with its associated individual suspension 26 hovers exactly below the plunger 32 and centrally above the weighing object carrier 122.

[0071] Figure 7 shows a state in which the plunger 32 is moved downward by means of the plunger motor 30, thereby pressing the individual suspension 26 of the largest weight 28 downward relative to the weight housing 20. In particular, this lowering occurs so far that the bottom of the weight 28 rests on the surface of the weighing object carrier 122. The individual suspension 26 is designed such that the weight 28 is released from it or from the weight housing 20 and rests solely on the weighing object carrier 122, so that the weighing sensor coupled to the weighing object sensor 122 can record an exact weight value for the weight 28.

[0072] Figure 8 shows three phases of such a lowering process. The individual suspension 26 essentially comprises a collar 261, which surrounds the neck of the weight 28, designed as a standard button weight, at a radial and vertical distance. The weight's head thus hangs on the collar 261. Above the head of the weight 28, the individual suspension 26 has a free space 262. The collar 261 and the free space 262 are formed by appropriately shaping a frame 263, which is mounted with a vertical undersize in a corresponding recess in the weight housing 20 for vertical linear displacement. In particular, the recess forms an upper stop 264 and a lower stop 265 for the frame 263. The frame 263 is spring-loaded against the upper stop 264 by compression springs 266. This situation is illustrated in Figure 8a.

[0073] By lowering the plunger 32, the frame 263 is displaced toward the lower stop 265 against the spring force of the compression springs 266. This lowers the weight 32 suspended from the collar 261. This state is shown in Figure 8b.

[0074] The lowering process is limited by the frame 263 striking the lower stop 265, as illustrated in Figure 8c. During actual operation of the device according to the invention, in particular during the transfer of the weight 28 to the weighing object carrier 122, the bottom of the weight 28 strikes the surface of the weighing object carrier 122 in the lowering position shown in Figure 8b. During the transition to the lowering position according to Figure 8c, the weight 8 can no longer follow the downward vertical movement of its individual suspension 26 (unlike shown in Figure 8c); rather, it lifts itself relative to the collar 261, thus freeing itself from it. Its weight then rests solely on the weighing object carrier 122.

[0075] Figure 9 again shows details of the individual suspension 26, namely in a side view (Figure 9a) and in a sectional view (Figure 9b) according to the sectional arrows in Figure 9a. It can be seen that the collar 261 does not completely surround the neck of the weight 28, but merges on one side into a flat, diagonally rising channel 267.

[0076] This makes it possible, as can be seen particularly from Figure 9b, to guide the head of the weight 28 into the channel and through it out of the individual suspension 26 by slightly tilting it. The neck of the weight 28 passes through a suitably dimensioned slot in the bottom of the channel 267. In the opposite manner, the weight 28 can be suspended in the individual suspension 26.

[0077] Of course, the embodiments discussed in the specific description and shown in the figures represent only illustrative embodiments of the present invention. In light of the disclosure herein, a wide range of possible variations is available to those skilled in the art.

[0078] List of reference symbols

[0079] 10 Weighing device

[0080] 12 scales

[0081] 121 Scale base body

[0082] 122 weighing carriers

[0083] 123 Weighing chamber wall

[0084] 124 Interface

[0085] 14 weight magazine

[0086] 141 magazine housing

[0087] 142 Magazine door

[0088] 144 Interface

[0089] 16 Swivel motor

[0090] 18 rail

[0091] 20 weight housings

[0092] 22 spindle drive

[0093] 24 sliding motor

[0094] 26 single suspension

[0095] 261 Neck brace

[0096] 262 open space

[0097] 263 frames

[0098] 264 upper stop

[0099] 265 lower stop

[0100] 266 compression spring

[0101] 267 Channel

[0102] 28 weights

[0103] 30 tappet motor

[0104] 32 tappets

Claims

Patent claims 1. Weighing device (10), comprising - a weighing sensor, a load carrier (122) and a weighing system coupling the load carrier (122) to the weighing sensor, - a weight magazine (14) with a plurality of weights stored therein (28) and - a transfer device by means of which the weights (28) can be placed on the weighing carrier (122) as required, characterized in that the weight magazine (14) is designed as a magazine housing (141) with a magazine door (142) pivotably mounted thereon, on the inside of which the weights (28) are held and by means of which said magazine housing (141) can be closed, wherein the magazine door (142) forms a horizontally longitudinally extended weight carrier and pivotable about a vertical pivot axis over the weighing carrier (122), on which the weights (28) are held in a manner that is jointly linearly movable in the longitudinal direction of the weight carrier and individually linearly movable vertically between a weight storage position and a weight weighing position.

2. Weighing device (10) according to claim 1, characterized in that the weight magazine (14) is arranged in direct contact with a weighing chamber surrounding the weighing carrier (122).

3. Weighing device (10) according to claim 2, characterized in that the weight magazine (14) is reversibly fixed in or on a weighing chamber wall (123), wherein an electrical and / or electronic interface (124, 144) of the weight magazine (14) contacts a corresponding interface of the weighing chamber wall (124). Weighing device (10) according to one of the preceding claims, characterized in that the magazine door (142) can be pivoted by means of a pivoting motor (16), wherein it can be temporarily fixed in a weighing pivot position in which each of the weights (28) can be positioned centrally above the weighing carrier (122) by a horizontal linear movement. Weighing device (10) according to claim 4, characterized in that the magazine housing (141) has a mechanical stop against which the magazine door (14) can be pressed by a motor in the weighing pivot position. Weighing device (10) according to claim 4, characterized in that the pivoting motor (16) is designed as a stepper motor. Weighing device (10) according to claim 4, characterized in that the pivoting motor (16) is provided with a rotary encoder.Weighing device (10) according to one of the preceding claims, characterized in that the weights (28) are suspended on individual suspensions (26) of a rigid, bottom-open weight housing (20) that is movable by a motor in the longitudinal direction of the magazine door (142). Weighing device (10) according to claim 8, characterized in that each individual suspension (26) is linearly displaceable vertically between a lower stop (265) and an upper stop (264). Weighing device (10) according to claim 9, characterized in that each individual suspension (26) is spring-loaded against its upper stop (264). Weighing device (10) according to any one of claims 8 to 10, characterized in that each weight (28) is suspended in its individual suspension (26) such that, when lifted relative to the individual suspension (26), it loses all mechanical contact with the weight housing (20).Weighing device (10) according to claim 11, characterized in that the weight (28) is designed as a rotationally symmetrical button weight with a head of a first diameter, a cylindrical body of a second diameter and a neck of a third diameter arranged between the head and the body, which is smaller than the first and the second diameter, wherein each individual suspension (26) has a cavity open at the bottom surrounding the head of the associated weight (28) with radial and axial interference, which is bounded downwards by a neck collar (261) projecting radially inwards with a clear width of a fourth diameter, which is smaller than the first diameter and larger than the third diameter.Weighing device (10) according to claim 12, characterized in that the cavity additionally has a lateral opening in the form of a flat channel (267) extending longitudinally transversely to the direction of travel of the weight housing (20), the clear channel profile of which is larger than the head profile of the associated weight piece (28) and the underside of which is provided with a slot extending through its longitudinal direction, the width of which is greater than the third diameter. Weighing device (10) according to claim 13, characterized in that the channel (267) is designed to rise obliquely towards the radial outside. Weighing device (10) according to any one of claims 8 to 14, insofar as it relates back to claim 4, characterized in that the weight housing (20) is motor-driven to different weighing positions, the number of which corresponds to the number of weights (28) and in which one of the weights (28), which then acts as the currently weighable weight (28), is positioned centrally above the weighing carrier (122), provided that the magazine door (142) is simultaneously in its weighing pivot position. Weighing device (10) according to claim 15, characterized in that a motor-driven plunger (32) is mounted on the magazine door (142), by means of which the individual suspension (26) on which the currently weighable weight piece (28) is suspended can be pressed down.Weight magazine (14), comprising a magazine door (142), one. Magazine housing (141) and a plurality of weights (28) that are movable together horizontally, wherein the weights (28) are held on the inside of the magazine door (142), which is pivotably mounted about a vertical pivot axis on the magazine housing (141) that can be closed by means of said magazine door (142), wherein the common horizontal movement of the weights (28) is linear in nature and the weights (28) are also individually movable vertically in a linear fashion between a weight storage position and a weight weighing position. Weight magazine (14), comprising a magazine door (142), a Magazine housing (141) and a plurality of weight bearings that are movable together horizontally, wherein the weight bearings are designed as individual suspensions (26) by means of which weights (28) shaped as button weights can be held on the inside of the magazine door (142), which is pivotably mounted about a vertical pivot axis on the magazine housing (141) which can be closed by means of said magazine door (142), wherein the common horizontal movement of the weight bearings is linear in nature and the individual suspensions (26) as well as the weights (28), if present, by means of their held weights, can be moved vertically linearly between a weight storage position and a weight weighing position.

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