Counterweight balanced press drive assembly and press

Abstract

This application discloses a counterweight-balanced press transmission assembly, including a main shaft, eccentric wheels, a connecting rod, and a sector-shaped counterweight. Two eccentric wheels are fixedly mounted on the main shaft and distributed at both ends. One end of the connecting rod is rotatably sleeved on the eccentric wheels, and the other end is connected to the press slide. The sector-shaped counterweight is fixedly mounted on the main shaft and located between the two eccentric wheels. The direction of the sector-shaped counterweight is opposite to the eccentric direction of the eccentric wheels, so that when the press slide moves downward, the sector-shaped counterweight moves upward. By setting a sector-shaped counterweight on the main shaft and making its direction opposite to the eccentric direction of the eccentric wheels, the counterweight moves upward when the slide moves downward for the stamping operation, thereby effectively balancing the unbalanced inertial forces generated by the eccentric wheels and connecting rod during rotation.

Description

Technical Field

[0001] This application relates to the field of press technology, and in particular to a counterweight-balanced press transmission assembly and press. Background Technology

[0002] A press is a general-purpose mechanical device widely used in processes such as stamping, forging, and die-cutting. Its core transmission mechanism typically employs a crank-connecting rod mechanism or an eccentric wheel-connecting rod mechanism, which converts the rotary motion of the motor into the reciprocating linear motion of the slide block, thereby applying pressure to the workpiece.

[0003] In traditional press transmission components, rotating parts such as eccentric wheels and connecting rods have significant eccentric mass. When the spindle rotates at high speed, this eccentric mass generates enormous centrifugal inertial forces, causing severe vibrations in the press body. This not only affects machining accuracy but also accelerates the wear of critical components such as bearings and guide rails, reducing the equipment's lifespan. Furthermore, the unbalanced inertial forces also cause periodic impacts on the press foundation, placing high demands on the installation environment. Summary of the Invention

[0004] The present invention aims to provide a counterweight balancing transmission assembly and press for a press, in order to solve the problems of large vibration and poor balancing effect caused by eccentric mass in the press in the prior art.

[0005] To achieve the above objectives, embodiments of the present invention provide a counterweight-balanced press transmission assembly, comprising: spindle; Two eccentric wheels are fixedly mounted on the main shaft and distributed at both ends of the main shaft; A connecting rod, one end of which is rotatably sleeved on the eccentric wheel, and the other end of which is connected to the press slide, is used to drive the press slide to move; A sector-shaped counterweight is fixedly mounted on the main shaft and located between the two eccentric wheels. The sector-shaped counterweight is positioned in the opposite direction to the eccentricity of the eccentric wheels, so that when the press slide moves downward, the sector-shaped counterweight moves upward.

[0006] Furthermore, the number of sector counterweights is adjustable, and the main shaft is provided with multiple counterweight mounting positions for selectively installing different numbers of sector counterweights according to dynamic balancing requirements.

[0007] Furthermore, there are three sector-shaped counterweights, which are arranged along the axial direction of the main shaft.

[0008] Furthermore, the center of mass of the sector-shaped counterweight is located on an arc centered on the rotation center of the main shaft, and the radius R of this arc is greater than the eccentricity e of the eccentric wheel.

[0009] Furthermore, the ratio k of the radius R of the arc to the eccentricity e of the eccentric wheel satisfies: 1.5 ≤ k ≤ 4.0.

[0010] Furthermore, the radius R of the center of mass of the sector-shaped counterweight is determined by the geometric parameters of the sector-shaped counterweight, including the inner radius R1, the outer radius R2, the central angle θ, and the thickness t. The radius R of the center of mass satisfies: ;

[0011] Where R1 is greater than the radius of the main shaft, R2 is less than the minimum distance between the inner wall of the press body and the rotation center of the main shaft, and θ ranges from 30° to 120°.

[0012] Furthermore, the spindle is a one-piece forged structure.

[0013] Furthermore, the main shaft is provided with a first mounting position and a second mounting position, and an eccentric wheel is installed at the first mounting position and the second mounting position respectively, and a sector-shaped counterweight is installed between the first mounting position and the second mounting position.

[0014] Furthermore, a bearing is installed on each side of each eccentric wheel.

[0015] Furthermore, a first mounting keyway is provided on both the first and second mounting positions, and a second mounting keyway is provided on the eccentric wheel. The eccentric wheel is mounted on the spindle through the keyway engagement.

[0016] Furthermore, a locking sleeve is provided on the bearing, which fixes the eccentric wheel and the bearings on both sides of the eccentric wheel together.

[0017] Furthermore, the sector-shaped counterweight includes a counterweight base and a counterweight top cover. The counterweight base is installed below the spindle, and the counterweight top cover is installed above the spindle. The counterweight top cover and the counterweight base are connected by threaded fasteners.

[0018] Furthermore, a power source is connected to one end of the spindle.

[0019] According to another aspect of the invention, a press is also provided, comprising a press transmission assembly with counterweight balancing as described above.

[0020] Furthermore, the press includes two sets of counterweight-balanced press transmission components. The main shafts of the two transmission components are parallel to each other and spaced apart. The two transmission components drive the same press slide together.

[0021] Furthermore, the main shafts of the two sets of transmission components are connected by a gear transmission mechanism and driven by the same power source, so as to realize the mechanical synchronous operation of the two sets of transmission components.

[0022] Furthermore, the main shafts of the two sets of transmission components are driven by independent power sources and maintain synchronous operation through a synchronous control system.

[0023] Furthermore, the synchronous control system includes angle position sensors respectively installed on the main shafts of the two sets of transmission components and a controller connected to the angle position sensors. The controller controls the output speed of the two independent power sources so that the eccentric wheels of the two sets of transmission components maintain the same phase.

[0024] By applying the technical solution of this invention, a sector-shaped counterweight is set on the main shaft, with its direction opposite to the eccentricity of the eccentric wheel. This allows the counterweight to move upwards when the slider moves downwards for stamping, effectively balancing the unbalanced inertial forces generated by the eccentric wheel and connecting rod during rotation. The sector-shaped counterweight's placement between the two eccentric wheels ensures that the balancing torque is evenly transmitted to both eccentric wheels, reducing the main shaft bending moment. The design of the sector-shaped counterweight's center of mass radius being larger than the eccentricity results in a smaller required counterweight mass for the same balancing torque, reducing the additional bending moment and rotational inertia of the main shaft. The adjustable number of counterweights allows for flexible adjustment of the dynamic balance according to actual working conditions, providing strong adaptability. The parallel arrangement of the dual transmission components is suitable for large-table presses, enabling uniform drive. This invention significantly reduces vibration and noise during press operation, improving equipment stability, processing accuracy, and service life.

[0025] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0026] The accompanying drawings are used to provide a further understanding of the technical solutions disclosed in this application and form part of the specification. They are used together with the embodiments disclosed in this application to explain the technical solutions of this application and do not constitute a limitation on the technical solutions disclosed in this application.

[0027] Figure 1 This is a schematic diagram of the overall structure of an embodiment of this application; Figure 2 This is an exploded view of an embodiment of this application; Figure 3 This is a schematic diagram of the mating structure of two transmission components according to an embodiment of this application; Figure 4 This is a schematic diagram of the structure of the press according to an embodiment of this application.

[0028] Reference numerals: 1. Main shaft; 12. First mounting position; 13. Counterweight mounting position; 14. Second mounting position; 2. Eccentric wheel; 3. Connecting rod; 4. Press slide block; 5. Sector-shaped counterweight; 51. Counterweight base; 52. Counterweight top cover; 6. Bearing; 7. Locking sleeve; 100. Machine body; 200. First transmission assembly; 300. Second transmission assembly; 400. Press slide block; 500. Gear transmission mechanism. Detailed Implementation

[0029] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.

[0030] In the description of this application, it should be understood that the orientation descriptions, such as up, down, front, back, left, right, etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0031] In the description of this application, "several" means one or more, "multiple" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. The use of "first" and "second" in the description is merely for distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.

[0032] In the description of this application, unless otherwise expressly defined, terms such as "setup," "installation," and "connection" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this application in conjunction with the specific content of the technical solution.

[0033] In the description of this application, the terms "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0034] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0035] Example 1 like Figure 1 and Figure 2 As shown, this embodiment provides a counterweight-balanced press transmission assembly. The transmission assembly includes a main shaft 1, two eccentric wheels 2, a connecting rod 3, a press slide block 4, and a sector-shaped counterweight 5.

[0036] The main shaft 1 is a one-piece forged structure, forged from high-strength alloy steel and then machined, possessing excellent strength and rigidity, capable of withstanding alternating loads and impact loads under high-speed rotation. Along its axial direction, the main shaft 1 is sequentially provided with a first main journal, a first mounting position 12, a counterweight mounting position 13, a second mounting position 14, and a second main journal. The first and second main journals are rotatably supported within the main bearing seats of the press body.

[0037] Two eccentric wheels 2 are fixedly mounted on the first mounting position 12 and the second mounting position 14 at both ends of the main shaft 1, respectively. The axis of each eccentric wheel 2 is parallel to but offset from the rotation axis of the main shaft 1, with an eccentricity of e. To achieve circumferential fixation, a first mounting keyway is provided on both the first mounting position 12 and the second mounting position 14, and a second mounting keyway is provided on the inner hole of the eccentric wheel 2. The eccentric wheel 2 is circumferentially locked to the main shaft 1 by a flat key, ensuring the reliability of power transmission.

[0038] The large end of the connecting rod 3 is rotatably mounted on the eccentric wheel 2, and the small end of the connecting rod 3 is connected to the press slide 4. When the main shaft 1 rotates, the eccentric motion of the eccentric wheel 2 is converted into the reciprocating linear motion of the press slide 4 through the connecting rod 3, thereby realizing the stamping process of the workpiece.

[0039] A sector-shaped counterweight 5 is fixedly mounted on the counterweight mounting position 13 of the main shaft 1. This mounting position 13 is located between the first mounting position 12 and the second mounting position 14, that is, the sector-shaped counterweight 5 is located between the two eccentric wheels 2. The orientation of the sector-shaped counterweight 5 is opposite to the eccentric direction of the eccentric wheels 2. Figure 2 As shown, when the eccentric direction of the eccentric wheel 2 is downward (i.e., the press slide 4 moves downward to perform the stamping operation), the fan-shaped main body of the fan-shaped counterweight 5 is located above the main shaft 1, and its center of mass moves upward.

[0040] The sector-shaped counterweight 5 adopts a split structure, including a counterweight base 51 and a counterweight top cover 52. The counterweight base 51 is installed below the main spindle 1, and the counterweight top cover 52 is installed above the main spindle 1. The two are connected by threaded fasteners (such as high-strength bolts) to securely hold the main spindle 1. This split structure does not require changes to the original structure of the main spindle 1, facilitates installation and disassembly, and allows for the replacement of sector-shaped counterweights 5 with different masses or quantities based on dynamic balance test results to achieve precise balance.

[0041] Example 2 This embodiment optimizes the bearing configuration based on Embodiment 1. For example... Figure 1 , 2 As shown, the main bearing is configured with multiple bearings 6, with one bearing 6 installed on each side of each eccentric wheel 2. That is, there is one bearing 6 on each side of the eccentric wheel 2 at the first mounting position 12, and one bearing 6 on each side of the eccentric wheel 2 at the second mounting position 14. All four bearings 6 are roller bearings used to bear radial loads.

[0042] To achieve overall fixation between the bearing 6 and the eccentric wheel 2, a locking sleeve 7 is provided on each bearing 6. The locking sleeve 7 axially locks the eccentric wheel 2 and the bearings 6 on both sides, forming a single unit. This structure improves assembly accuracy and overall rigidity, prevents axial movement, and extends bearing life.

[0043] Example 3 Based on Example 1, this embodiment optimizes the design of the center of mass position of the sector-shaped counterweight 5.

[0044] The center of mass of the sector-shaped counterweight 5 is located on an arc centered on the rotation center of the main shaft, and the radius R of this arc is greater than the eccentricity e of the eccentric wheel 2. In this embodiment, the ratio of R to e is k=1.8, i.e., R=1.8e. Calculations show that the mass of the sector-shaped counterweight 5 is approximately 55.6% of the equivalent eccentric mass of the eccentric wheel 2 and its associated components. Compared to the traditional counterweight scheme (requiring 100% mass when R=e), the counterweight mass is significantly reduced.

[0045] The geometric parameters of the sector-shaped counterweight 5 are designed based on the target centroid radius R. Let the inner radius of the sector-shaped counterweight 5 be... The radius of the fan-shaped counterweight 5 is R1 (slightly larger than the radius of the main shaft 1), the outer radius is R2 (smaller than the minimum distance between the inner wall of the press body and the rotation center of the main shaft), the central angle is θ, the thickness is t, and the material density is ρ. The radius R of the center of mass of the fan-shaped counterweight 5 satisfies: ;

[0046] The mass of the sector-shaped counterweight ; Where ρ is the material density; Furthermore, the sector-shaped counterweight satisfies the balance condition. ;

[0047] in, Let e ​​be the equivalent eccentric mass of the eccentric wheel and its associated components, and let e be the eccentricity.

[0048] In a preferred embodiment of this example, R1=45mm, R2=120mm, θ=90°, and the calculated values ​​are R≈92.5mm, e=51.4mm, and k≈1.8, which are consistent with the design target.

[0049] To further optimize the balancing effect, the radius ratio k was optimized. Six prototypes with k=1.2, 1.5, 2.0, 2.5, 3.8, and 4.0 were designed while ensuring sufficient structural space. The balancing effects were compared through finite element analysis and field vibration testing. The experimental results show that: When k=1.2, the mass of the counterweight is 83.3% of the eccentric mass, the additional bending moment of the main shaft decreases by about 17%, and the vibration acceleration decreases by about 12%. When k=1.5, the mass of the counterweight is 66.7% of the eccentric mass, the additional bending moment of the main shaft is reduced by about 33%, and the vibration acceleration is reduced by about 28%. When k=2.0, the mass of the counterweight is 50% of the eccentric mass, the additional bending moment of the main shaft is reduced by about 50%, and the vibration acceleration is reduced by about 42%. When k=2.5, the mass of the counterweight is 40% of the eccentric mass, the additional bending moment of the main shaft is reduced by about 60%, and the vibration acceleration is reduced by about 48%. When k=3.8, the mass of the counterweight can be reduced to 26.3% of the eccentric mass, the additional bending moment of the main shaft is reduced by about 73.7%, and the vibration acceleration is reduced by about 60%. When k=4.0, the mass of the counterweight is 25% of the eccentric mass, the additional bending moment of the main shaft is reduced by about 75%, and the vibration acceleration is reduced by about 62%.

[0050] Taking into account the balance effect, structural space and manufacturing cost, the optimal value of k is 1.5 to 4.0. At this value, good balance performance can be guaranteed while maintaining a compact structure and manufacturability.

[0051] Example 4 This embodiment provides a press, including a machine body, a main bearing housing, and a press transmission assembly for counterweight balancing as described in any one of embodiments 1 to 3. A main bearing is installed in the main bearing housing of the machine body to support the first and second main journals of the main shaft 1. The drive end of the main shaft 1 is connected to a motor via a pulley to receive power. When the motor drives the main shaft 1 to rotate, the eccentric motion of the eccentric wheel 2 drives the press slide 4 to move up and down via the connecting rod 3. The fan-shaped counterweight 5 rotates synchronously with the main shaft 1, and the centrifugal inertial force it generates is opposite in direction and equal in magnitude to the centrifugal inertial force generated by the eccentric wheel 2, connecting rod 3, etc., thereby essentially canceling out the unbalanced force of the system and making the press run smoothly.

[0052] Example 5 This embodiment provides a press, which includes two sets of counterweight-balanced press transmission components. The main shafts of the two sets of transmission components are parallel to each other and spaced apart, and jointly drive the same press slide. It is suitable for stamping conditions with large table size and large tonnage.

[0053] like Figure 3 , 4 As shown, the press includes a machine body 100, a first transmission assembly 200, a second transmission assembly 300, and a press slide 400. The first transmission assembly 200 and the second transmission assembly 300 are arranged parallel to each other and spaced apart within the machine body 100, and their main shafts 1 are parallel to each other. The first transmission assembly 200 and the second transmission assembly 300 have the same structure, both employing a counterweight-balanced press transmission assembly as described in any one of embodiments 1 to 4.

[0054] Synchronous drive method of parallel spindle Two sets of parallel and spaced-apart spindles 1 can be driven synchronously using one of the following two methods: Method 1: Mechanical synchronous drive The main shafts 1 of the two transmission components are connected by a gear transmission mechanism 500 and driven by the same power source. Specifically, the output shaft of the power source (such as a main motor) is connected to a driving gear, which meshes with a first driven gear mounted on the main shaft 1 of the first transmission component 200. Simultaneously, the first driven gear meshes with a second driven gear mounted on the main shaft 1 of the second transmission component 300. Through gear transmission, the two main shafts 1 achieve equal-speed counter-rotation or equal-speed same-direction rotation (determined by the gear configuration). To ensure that the eccentric wheels 2 of the two transmission components move in the same phase, the transmission ratio of the gear transmission mechanism 500 is set to 1:1, and the eccentric wheels 2 on the two main shafts 1 are installed in the same phase. This mechanical synchronization method has a simple structure, high synchronization reliability, and is suitable for presses with a small center distance between the two main shafts.

[0055] Method 2: Independent drive + electrical synchronous control The two sets of transmission components' spindles 1 are each driven by an independent power source (such as two servo motors) and equipped with a synchronization control system. The synchronization control system includes an angle position sensor (such as an encoder or rotary transformer) installed at the driven end of each set of transmission component spindles 1, and a controller connected to the angle position sensor signal. The controller acquires the rotation angle signals of the two sets of transmission component spindles 1 in real time and adjusts the output speed of the two motors through the servo drive unit, ensuring that the eccentric wheels 2 of the two sets of transmission components always maintain the same phase angle, achieving electrical synchronization. The advantage of this method is that the working mode can be flexibly adjusted according to process requirements, making it suitable for conditions with a large center distance between the two spindles or higher requirements for synchronization accuracy.

[0056] In the dual-drive press, each drive assembly is dynamically balanced independently. The opposite orientation of the sector counterweight 5 and the eccentric wheel 2 ensures that the unbalanced forces of each drive assembly are essentially canceled out. Simultaneously, the two drive assemblies are arranged in parallel, and a synchronous drive mechanism ensures complete synchronization of their motion phases. This results in the driving force transmitted to the press slide 400 by both drive assemblies being evenly distributed along the slide width, further enhancing the overall dynamic balance performance of the machine.

[0057] Because the sector-shaped counterweight 5 is located between the two eccentric wheels 2 of the main shaft 1 of each transmission assembly, and the radius R of the center of mass of the sector-shaped counterweight 5 is greater than the eccentricity e, the additional bending moment of the main shaft 1 of each transmission assembly is small, and the moment of inertia is low. When applied to a dual-transmission assembly press, the overall system has better dynamic performance and faster start-stop response.

[0058] Example 6 Based on Example 1, this embodiment improves the number and configuration of the sector-shaped counterweights to achieve flexible adjustment of dynamic balance.

[0059] Option 1: Three sector-shaped counterweights like Figure 1 As shown, there are three sector-shaped counterweights 5, which are spaced apart along the circumference of the main shaft 1 and located between the two eccentric wheels 2. The central angle of each of the three sector-shaped counterweights 5 is 120°, they are evenly distributed along the circumference of the main shaft 1, and the setting direction of each sector-shaped counterweight 5 is opposite to the eccentric direction of the eccentric wheel 2.

[0060] The three sector-shaped counterweights 5 together provide the balancing torque, and their total mass is the sum of the masses of the three sector-shaped counterweights 5. The total radius of their center of mass is the resultant radius of their center of mass. By rationally designing the mass and distribution angle of each sector-shaped counterweight 5, a more precise dynamic balance effect can be achieved.

[0061] During assembly, the three sector-shaped counterweights 5 are respectively fixed to the counterweight mounting positions 13 of the main shaft 1 by threaded fasteners. The counterweight mounting positions 13 are provided with three mounting areas corresponding to the three sector-shaped counterweights 5 along the circumference of the main shaft 1. Each mounting area is provided with a keyway and a threaded hole for positioning and fixing the sector-shaped counterweights 5.

[0062] The distribution of the three sector-shaped counterweights 5 can be adjusted according to the balance requirements: When the maximum balancing torque is required, all three sector-shaped counterweights 5 are installed with their centers of mass on the same side, together generating a balancing torque opposite to that of the eccentric wheel 2. When a moderate balancing torque is required, two of the sector-shaped counterweights 5 can be selectively installed; When a smaller balancing torque is required, only one sector counterweight 5 can be installed.

[0063] Option 2: The number of sector-shaped counterweights is adjustable. To further improve flexibility and adaptability, this embodiment provides a structural design in which the number of sector-shaped counterweights 5 is adjustable.

[0064] In some embodiments, the counterweight mounting position 13 of the spindle 1 is provided with multiple counterweight mounting positions, which are evenly distributed along the axial direction of the spindle 1. Each mounting position is provided with a keyway and a threaded hole for fixing the sector-shaped counterweight 5. The sector-shaped counterweight 5 is a standardized modular component, and each sector-shaped counterweight 5 has the same geometry and mass, or can be provided with various specifications according to design requirements.

[0065] During the assembly or debugging of the press, the operator can selectively install an appropriate number of sector-shaped counterweights 5 based on the dynamic balance test results. The specific adjustment method is as follows: Initial assembly: First, assemble the main shaft 1, eccentric wheel 2, connecting rod 3 and other components, install them on the dynamic balancing machine for testing, and measure the magnitude and phase of the initial imbalance.

[0066] Calculate the required balancing torque: Based on the initial imbalance, calculate the centrifugal inertial force that needs to be counteracted, thereby determining the total mass torque of the required counterweight. , Select the number of sector-shaped counterweights: based on the mass of a single sector-shaped counterweight 5. and centroid radius Calculate the required number of counterweights. : ; The number of units to be installed is determined after rounding down.

[0067] Install sector counterweights: Based on the phase direction of the imbalance, install a selected number of sector counterweights 5 at the corresponding angular positions on the main shaft 1, ensuring that the center of mass of the sector counterweights 5 is located in the opposite direction to the eccentric direction of the eccentric wheel 2.

[0068] Re-testing and fine-tuning: After installation, perform dynamic balance test again. If the residual imbalance still exceeds the allowable range, fine-tuning can be performed by replacing the sector counterweight 5 with one of different mass or by removing a small amount of material from the sector counterweight 5 (e.g., drilling holes).

[0069] Work process The working process of the counterweight balancing press transmission assembly of the present invention is as follows: Start the power source, which drives the main shaft 1 to rotate. The main shaft 1 drives the two eccentric wheels 2 and the sector-shaped counterweight 5 fixed on it to rotate synchronously.

[0070] When the eccentric wheel 2 rotates from the highest point to the lowest point, the connecting rod 3 drives the press slide 4 to move downwards, performing the stamping operation. Simultaneously, the fan-shaped main body of the fan-shaped counterweight 5 moves from the lowest point to the highest point, meaning its center of mass moves upwards. The centrifugal inertial force generated by the fan-shaped counterweight 5 is in the opposite direction to the centrifugal inertial force generated by the eccentric wheel 2 and the connecting rod 3; the two cancel each other out, thus significantly reducing the periodic dynamic load transmitted to the press body.

[0071] When the eccentric wheel 2 rotates from the lowest point to the highest point, the press slide 4 returns upward, and the center of mass of the fan-shaped counterweight 5 moves downward, thus maintaining the offsetting relationship of the balancing torque.

[0072] By designing the radius R of the center of mass of the sector counterweight 5 to be greater than the eccentricity e, the mass of the counterweight is minimized under the premise of generating the same balancing torque, thereby reducing the additional bending moment and rotational inertia of the main shaft 1 and improving the dynamic response performance.

[0073] The embodiments of this application effectively counteract the unbalanced inertial force generated by the rotating components by setting the fan-shaped counterweight in the opposite direction to the eccentric wheel, so that the press can still run smoothly at high speeds, reducing vibration amplitude and noise.

[0074] The embodiments of this application have been described in detail above with reference to the accompanying drawings. However, this application is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of this application. Furthermore, unless otherwise specified, the embodiments and features described in the embodiments of this application can be combined with each other.

Claims

1. A counterbalanced press drive assembly characterized by, include: spindle; Two eccentric wheels are fixedly mounted on the main shaft and distributed at both ends of the main shaft; A connecting rod, one end of which is rotatably sleeved on the eccentric wheel, and the other end of which is connected to the press slide, is used to drive the press slide to move; A sector-shaped counterweight is fixedly mounted on the main shaft and located between the two eccentric wheels. The sector-shaped counterweight is positioned in the opposite direction to the eccentricity of the eccentric wheels, so that when the press slide moves downward, the sector-shaped counterweight moves upward.

2. A counterbalanced press drive assembly according to claim 1, characterized in that, The number of the sector-shaped counterweights is adjustable, and the main shaft is provided with multiple counterweight mounting positions for selectively installing different numbers of sector-shaped counterweights according to dynamic balancing requirements.

3. The counterweight balancing press transmission assembly according to claim 1, characterized in that, The center of mass of the sector-shaped counterweight is located on an arc centered on the rotation center of the main shaft, and the radius R of the arc is greater than the eccentricity e of the eccentric wheel.

4. The counterweight-balanced press transmission assembly according to claim 3, characterized in that, The ratio k of the radius R of the arc to the eccentricity e of the eccentric wheel satisfies: 1.5 ≤ k ≤ 4.

0.

5. The counterweight balancing press transmission assembly according to claim 4, characterized in that, The radius R of the centroid of the sector-shaped counterweight is determined by its geometric parameters, including the inner radius R1, outer radius R2, central angle θ, and thickness t. The radius R satisfies the following: ； Wherein, R1 is greater than the radius of the main shaft, R2 is less than the minimum distance between the inner wall of the press body and the rotation center of the main shaft, and θ ranges from 30° to 120°.

6. The counterweight balancing press transmission assembly according to claim 1, characterized in that, The main shaft is provided with a first mounting position and a second mounting position, and an eccentric wheel is respectively installed at the first mounting position and the second mounting position. The sector-shaped counterweight is installed between the first mounting position and the second mounting position.

7. The counterweight balancing press transmission assembly according to claim 10, characterized in that, Each of the eccentric wheels has a bearing installed on each side.

8. The counterweight-balanced press transmission assembly according to claim 6, characterized in that, A locking sleeve is provided on the bearing, which fixes the eccentric wheel and the bearings on both sides of the eccentric wheel together.

9. The counterweight balancing press transmission assembly according to claim 1, characterized in that, The sector-shaped counterweight includes a counterweight base and a counterweight top cover. The counterweight base is installed below the main shaft, and the counterweight top cover is installed above the main shaft. The counterweight top cover and the counterweight base are connected by threaded fasteners.

10. A press, characterized in that, Includes a counterweight-balanced press transmission assembly as described in any one of claims 1-9.

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