A dosing device with impact piston

Abstract

The invention relates to a dosing device comprising a torque transmission apparatus (40) with a torque shaft (42) connected to a drive apparatus (30) generating torque and a shaft bearing (44) in which the torque shaft (42) is rotatably supported on an extension axis (x); a scoop apparatus (20) with a scoop element (22) rotated on the extension axis from a front end of the torque shaft (42), and a load cell (50) adapted to weigh the scoop apparatus, and a weighing method. The dosing device comprises a pusher piston (70) having a piston rod (73) linearly guided to apply an impact causing vibrations to the scoop element (22) in a discharge position adjacent to the shaft bearing (44).

Description

[0001] A DOSING DEVICE WITH IMPACT PISTON

[0002] TECHNICAL FIELD

[0003] The present invention relates to a dosing device, in particular to a dosing device with a dosing scoop for gravimetric feeding of powder-like products into processing machines.

[0004] BACKGROUND OF THE INVENTION

[0005] A dosing device with a gravimetric feeding scoop is a precise and effective system that allows the weighing of raw materials or components in predetermined ratios in industrial processes. These systems control the flow of materials based on the principle of gravity and generally work together with weighing sensors or load cells to measure the weight of the material in real-time. This allows gravimetric feeding scoops to provide a continuous and stable flow, offering high levels of accuracy and repeatability in production processes. They are widely used in various sectors such as plastics, food, chemicals, and pharmaceuticals, offering advantages such as cost savings, improved product quality, and reduced waste.

[0006] Gravimetric feeding scoops consist of a series of components that work together to ensure the correct material flow in the right proportions.

[0007] These components include hoppers where the materials are stored and included in the feeding process, precise weighing systems that continuously measure the material quantity in the hopper, and feeding mechanisms used to adjust the flow rate of the materials.

[0008] The working principle of gravimetric feeding scoops is to ensure the material flow through the combination of gravity and weighing systems.

[0009] During the process, the material weight in the hopper is continuously measured by the weighing system. The obtained weight value is compared with the predetermined target value, and the feeding mechanism adjusts the material flow rate to reach the target value. This process is important for ensuring a continuous and stable material flow and achieving high levels of accuracy and repeatability in production processes. SUMMARY OF THE INVENTION

[0010] The object of the invention is to provide a weighing system that reduces residues within the scoop element during the discharge process of the weighed product.

[0011] In order to achieve the aforementioned object, the invention relates to a dosing device comprising a torque transmission apparatus with a torque shaft connected to a drive apparatus generating torque and a shaft bearing in which the torque shaft is rotatably supported on an extension axis; a scoop apparatus with a scoop element rotated on the extension axis from a front end of the torque shaft, and a load cell adapted to weigh the scoop apparatus. The dosing device includes a pusher piston having a piston rod linearly guided to apply an impact causing vibrations to the scoop element in a discharge position adjacent to the shaft bearing. The impact of the pusher piston on the scoop element in the discharge position ensures the removal and discharge of the scoop weighing products, such as powders, adhering to the inner wall of the scoop element with low forces due to vibrations caused by the impact.

[0012] Preferably, the structure provided between the shaft bearing and the scoop element includes a front wall and a support hole aligned with a bearing element that directly stabilizes the pusher piston within the piston rod by opening in the front wall. The front wall can be a housing structure covering elements outside the scoop apparatus or a single panel. The front wall acts as a separator between the shaft bearing and the scoop element, enabling the fixation of the pusher piston on the shaft bearing with the bearing element, thus eliminating the need for an additional bearing element. The bearing element is preferably a holder part fixed at one end to the front wall and carrying the pusher piston without hindering the advancement movement at the other end.

[0013] Preferably, the pusher piston is placed perpendicular to the front wall in a discharge position to contact the scoop element from the front end of the piston rod. In this way, the impact force of the pusher piston applies an impact to the scoop element without any other component in the direction of the advancement force component, thus increasing the discharge efficiency.

[0014] Preferably, the pusher piston is fixed in a support hole on the front wall carried by the bearing element. Thus, the bearing element aligns and supports the pusher piston in the support hole, providing a compact and easy-to-maintain apparatus. Preferably, the pusher piston includes a drive portion in a housing structure extending around the support hole on the inward-facing part of the front wall, mostly accommodating the piston rod. In this case, a telescopic structure is obtained, protecting the piston rod in the housing except in a discharge position, for example, in a park position.

[0015] Preferably, the scoop element impacted by the front end of the pusher piston is made of metal material. This way, the impact effect creates vibrations with the natural frequency of the material, helping the removal of the conveyed product, for example, in powder form, from the scoop element not only at the moment of impact but also during the vibration process by overcoming electrostatic forces.

[0016] Preferably, the linear guiding axis of the pusher piston is adjusted adjacent to the mouth of the scoop element. In this way, the stroke distance of the pusher piston is reduced, and a compact apparatus is obtained.

[0017] Preferably, the extension axis of the piston rod is adjusted parallel to the extension axis of the torque shaft. In this case, a compact apparatus is obtained by bringing the pusher piston closer to the torque shaft.

[0018] A preferred application is a product weighing method with the dosing device described above. The method includes the steps of supplying the product to be weighed in a loading position to a scoop element with the mouth facing upward; weighing the product reaching a predetermined weight by the load cell; rotating the scoop element by the torque shaft to face downward in a discharge position; and advancing the pusher piston axially to push the scoop element from the outer periphery of the piston rod to create a vibration impact.

[0019] BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is a perspective view of a representative construction of the dosing device with the scoop facing upward.

[0021] Figure 2 is a cross-sectional view of the dosing device given in Figure 1.

[0022] Figure 3 is a side view of the dosing device with the housing cover removed, showing the pusher piston. DETAILED DESCRIPTION OF THE INVENTION

[0023] In this detailed description, the development subject of the invention is described with references to examples without any limitation and only to better explain the subject.

[0024] In Figure 1 , the gravimetric dosing and dosing device, a scoop apparatus (20) extending from a front wall (12) of a housing (10) with a scoop element (22), is shown in a perspective view with the filling position facing upward. A hole (16) is opened in the flat front wall (12) of the box-like housing (10) formed by combining flat panels. From the hole (16), a connection shaft (26) in cylindrical form extends outward from a front end. The connection shaft (16) extends horizontally on an extension axis (x) perpendicular to the front wall (12). The connection shaft (16) is fixed to the scoop element (22) from the front end. From the lower edge of the housing (10), flange-like feet (14) extend outward in opposite directions as a flat panel structure. There are screw holes on the feet (14) for fixing to a platform. The scoop element (22) is an empty hemispherical form with a circular mouth facing upward in a filling position of the scoop apparatus (20). In a discharge position, the mouth of the scoop (20) rotates by 90 degrees to pour the measured product in the enclosed chamber, such as a powder chemical, downward by its weight. An impact piston (70) extends parallel to the connection shaft (26) above the hole (16) on the front wall (12) and is adjusted to apply an impact from the outer periphery of the scoop apparatus (20) in a linear advancement direction.

[0025] In Figure 2, the same dosing device is shown in a cross-sectional view with the scoop apparatus (20) in the filling position. A drive apparatus (30) with a rotary piston structure includes a piston bearing (34) and a rotary piston (32) element. The piston bearing (34) supports the piston (32) aligned on the extension axis (x). The piston (32) is adjusted to rotate in both directions on the extension axis (x). A torque transmission apparatus (40) engages the piston (32) at the front end to transmit torque from a rear end of the torque shaft (42). The torque shaft (42) is a shaft extending on the extension axis (x). The front end of the torque shaft (42) transmits torque to the rear end of the connection shaft (26) by a shape fit. The torque shaft (42) is rotatably supported at both ends by bearings in a shaft bearing (44). The shaft bearing (44) is fixed on a slide (60) within the housing (10) aligned on the extension axis (x). The slide (60) aligns the shaft bearing (44) on a base plate of the housing (10) and elevates it.

[0026] A hammer element (46) with a ring at the end and a radial arm extends outward from the piston (32) and is rotatably mounted. The hammer element (46) limits the rotation of the piston (32) within a boundary angle. For this purpose, a planar stopper bearing (48) is placed at the ends of the 180-degree boundary angle (a) swept by the arm of the hammer element (46) adjacent to the hammer element (46). When the piston (32) rotates in one direction, it rotates the hammer element (46) until the arm contacts the corresponding stopper bearing (48), blocking further rotation. When the arm of the hammer element (46) touches the stopper bearing (48), the stopper bearing (48) blocks the rotation. Therefore, the piston (32) is now only free to rotate in the opposite direction. A magnetic connection element (47), which is a magnet, is fixed on the stopper bearing (45). The hammer element (46) is made of ferromagnetic material. When the arm of the hammer element (46) reaches the stopper bearing (45), the corresponding face of the element (22) impacted by the front end (72) of the pusher piston (70) being made of metal material. arm magnetically sticks to the magnetic connection element (47). In this way, the magnetic force prevents the arm from rebounding due to momentum when hitting the stopper bearing (45) due to its radial speed.

[0027] At the front end of the torque shaft (42), a load cell (50) connected to the slide (60) is provided. The load cell (50) measures the weight through the stress caused by the load applied to the torque shaft (42) directly supported by the connection shaft (26). The load cell (50) extends perpendicular to the base plate of the housing (10). A carrier element (24) is mounted between the scoop element (22) and the front wall (12) attached to the scoop element (22). The carrier element (24) is a metal plate structure fixedly mounted to the upper front end of the vertically extending connection shaft (26). At the rear end of the connection shaft (26), a projection extends along the length. This projection fits into a corresponding slot at the front end of the torque shaft (42) for torque transmission. The connection shaft (26) is only supported by the torque shaft (42) on the extension axis (x), and in the case of needing disassembly, it can be simply pulled outward to remove it. In this case, the projection at the front end of the connection shaft (26) exits the slot-shaped slot without any obstacle. The connection shaft (26) is pulled out from the hole (16) and can be taken out together with the scoop apparatus (20) mounted to its front end.

[0028] At the top of the connection shaft (26), the pusher piston (70) extends parallel and passes through a corresponding hole on the front wall (12), with the front end (72) extending to reach the scoop element (22) from the outer periphery with the advancement movement of the piston. The drive portion (74) of the pusher piston (70) is mounted on the shaft bearing (44).

[0029] Since the diameter of the hole (16) on the front wall (12) is larger than the diameter of the connection shaft (26), the connection shaft (26) can rotate without contacting the front wall (12). The dosing device is operated by being fixed through the feet (14) to a chemical component feeding machine, for example. In the filling position, for example, the powder material is filled into the scoop element (22) through its mouth. The stress caused by the additional load on the scoop element (22) on the connection shaft (26) is read by the load cell (50) through displacement, and weighing is performed, and the weighing information is electrically transmitted as a signal to a main controller (not shown). When a position change approval comes from the controller, for example, when the load cell shows a predetermined weight value, the drive apparatus (30) is operated. At this time, the hammer element (46) is attached to the stopper bearing (48) with the magnetic connection element (47). The piston (32) applies a reverse torque to overcome the magnetic force, separating the hammer element (46) from the corresponding stopper bearing (48). The torque of the piston (32) rotates the torque shaft (42) in the extension axis (x) with the help of bearings within the shaft bearing (44). Thus, torque is transmitted from the front end of the torque shaft (42) to the rear end of the connection shaft (26) through the shape fit, and the scoop apparatus (20) is rotated 180 degrees toward the discharge position by transmitting torque through the torque shaft (42) to the shaft bearing (44). This way, the material filled and weighed in the scoop element (22) is poured out by gravity. For the discharge of the material adhering to the inner wall of the scoop element (22) due to electrostatic forces, moisture, or other weak bonds, the pusher piston (70) is activated in the discharge position, and by applying an impact to the outer periphery of the scoop element (22) from the front end (72), ensures the remaining material is detached and discharged by vibrations. At this time, the scoop element (22) stops at the boundary angle (a) by the hammer element (46) resting on the opposite stopper wall (48) to guarantee stopping. The stopper wall (45) is mounted on the slide (60) in a T-like bearing structure, extending symmetrically along the extension axis (x).

[0030] Figures 2 and 3 show the dosing device with the side walls of the housing (10) removed. A controller (1) is connected to the pusher piston (70) for pneumatic control. The front end (72) of the pusher piston (70) extends outside the housing (10) and passes through a narrow support hole (13) spaced above the hole (16) on the front wall (12). The rest of the piston rod (73) extends within the housing (10) behind the front wall (12) in a drive portion (74) of the housing structure. The diameter of the piston rod (73) is set smaller than the diameter of the support hole (13). Thus, it can advance from the drive portion (74) and pass through the support hole (13). A connection element (76) is fixedly mounted around the support hole (13) in a bushing form facing outward towards the scoop element (22). As seen in Figure 3, the front end (72) of the piston rod (73) is placed within the connection element (76). The bearing element (71) has a U-like profile and is mounted on the inner face of the front wall (12) through feet (75) extending outward from its free ends. The drive portion (74) is stabilized in the housing (10) by placing the front end in the hole at the rear end of the bearing element (71). Thus, the pusher piston (70) is fixed on the outer face of the front wall (12) through the connection element (76) and on the inner face of the front wall (12) through the bearing element (71) resting against the inner face of the front wall (12) through the pressure of the feet (75). Although the drive portion (74) extending perpendicular to the inner face of the front wall (12) particularly supports a significant extension of the piston rod (73) in the loading position, the bearing element (71 ) provides sufficient support force to prevent the pusher piston (70) from bending, even if it applies a moment towards the support hole (13) due to its weight.

[0031] In the discharge position, the scoop element (22) is inverted by the torque shaft (42) to bring its open mouth downward, and the weighed product (u) inside is discharged by gravity. With the controller’s (1 ) triggering, the pusher piston (70) pneumatically driven, advances linearly through the support hole (13), allowing the front end (72) to impact the outer wall of the scoop element (22), ensuring the remaining part of the weighed product (u) that could not be discharged and adhered to the inner wall of the scoop element (22) due to, for example, electrostatic forces, is also removed.

[0032] REFERENCE NUMBERS

[0033] 1 Controller

[0034] 10 Housing

[0035] 12 Front wall

[0036] 13 Support hole

[0037] 14 Foot

[0038] 16 Hole

[0039] 20 Scoop apparatus

[0040] 22 Scoop element

[0041] 24 Carrier element

[0042] 26 Connection shaft

[0043] 30 Drive apparatus

[0044] 32 Piston

[0045] 34 Piston bearing

[0046] 40 Torque transmission apparatus

[0047] 42 Torque shaft

[0048] 44 Shaft bearing

[0049] 45 Stopper wall 46 Hammer element

[0050] 47 Magnetic connection element

[0051] 48 Stopper bearing

[0052] 50 Load cell 60 Slide

[0053] 70 Pusher piston

[0054] 71 Bearing element

[0055] 72 Front end

[0056] 73 Piston rod 74 Drive portion

[0057] 75 Foot

[0058] 76 Connection element a Boundary angle u Weighed product x Extension axis

Claims

CLAIMS1. A dosing device comprising a torque transmission apparatus (40) with a torque shaft (42) connected to a drive apparatus (30) generating torque and a shaft bearing (44) in which the torque shaft (42) is rotatably supported on an extension axis (x); a scoop apparatus (20) with a scoop element (22) rotated on the extension axis from a front end of the torque shaft (42), and a load cell (50) adapted to weigh the scoop apparatus, characterized by a pusher piston (70) having a piston rod (73) is linearly guided to apply an impact causing vibrations to the scoop element (22) in a discharge position adjacent to the shaft bearing (44).

2. A dosing device according to claim 1 , wherein a panel structure is provided between the shaft bearing (44) and the scoop element (22) including a front wall (12) and a support hole (13) aligned with a bearing element (75) that directly stabilizes the pusher piston (70) within the piston rod (72) by opening in the front wall (12).

3. A dosing device according to claim 2, wherein the pusher piston (70) is disposed perpendicular to the front wall (12) in a discharge position to contact the scoop element (22) from the front end of the piston rod (73).

4. A dosing device according to claims 2 or 3, wherein the pusher piston (70) is fixed in the support hole (13) on the front wall (12) carried by the bearing element (75).

5. A dosing device according to claims 2-4, wherein the pusher piston (70) is having a drive portion (74) in a housing structure extending around the support hole (13) on the inward-facing part of the front wall (12), mostly accommodating the piston rod (73).

6. A dosing device according to claims 2-5, wherein the scoop element (22) impacted by the front end (72) of the pusher piston (70) is made of metal material.

7. A dosing device according to any of the preceding claims, wherein the linear guiding axis of the pusher piston (70) is adjusted adjacent to the mouth of the scoop element (22).

8. A dosing device according to any of the preceding claims, wherein the extension axis of the piston rod (73) is adjusted parallel to the extension axis of the torque shaft (42).

9. A method for dosing a product with the dosing device according to any of the preceding claims, wherein the steps of: supplying the product to be weighed (u) in a loading position to a scoop element (22) with the mouth facing upward; weighing the product reaching a predetermined weight by the load cell (50); rotating the scoop element (22) by the torque shaft (42) to face downward in a discharge position; and advancing the pusher piston (70) axially to push the scoop element (22) from the outer periphery of the piston rod (72) to create a vibration impact.

Images