Lightweight high-rigidity servo press

Abstract

The utility model discloses a light-weight high-rigidity servo press, which relates to the technical field of press fitting, and is characterized in that the light-weight high-rigidity servo press comprises a turning seat and a rear cover fixed on the turning seat, a cylinder barrel is fixed on the rear cover, a front cover is fixed at one end, far away from the rear cover, of the cylinder barrel, and the light-weight high-rigidity servo press further comprises a planetary roller screw rod, the planetary roller lead screw comprises a lead screw and a roller nut connected with the lead screw, the lead screw is rotationally connected into the cylinder barrel, a driving assembly used for driving the lead screw to rotate is arranged on the turning seat, a piston rod is slidably connected into the cylinder barrel in the axial direction and is a hollow cylindrical component, a copper sleeve is arranged in the front cover, and the length of the copper sleeve is not smaller than that of the front cover. One end of the piston rod extends out of the front cover along the copper sleeve, the other end of the piston rod is sleeved and fixed on the roller nut, an anti-rotation key is embedded outside the piston rod, and a sliding groove for the anti-rotation key to axially slide is arranged on the inner wall of the cylinder barrel. The utility model has the advantages of light weight, high rigidity, good space adaptability and smooth and stable operation.

Description

Technical Field

[0001] The utility model relates to the technical field of press-fitting, and more specifically, to a lightweight and high-rigidity servo press. Background Art

[0002] With the rapid development of assembly and manufacturing industries and the continuous improvement of living standards, people's requirements for product quality are constantly increasing, thus putting forward higher requirements for processed and assembled products. For the assembly of many key parts such as bearings, screws, engine tensioners, etc., it is required not only to control the resulting assembly force, but also to control the force and displacement of the assembly process, so higher requirements are put forward for assembly equipment. In the past, the press-fitting of press-fitting equipment was mainly achieved by pneumatic cylinders or hydraulic cylinders. The problem brought by this method is that the press-fitting force changes with the change of air pressure and hydraulic pressure, but the precise control of air pressure and hydraulic pressure is relatively difficult and costly; in addition, the elasticity of compressed gas and the response lag of the hydraulic system make it impossible to accurately control the press-fitting position.

[0003] In order to solve the above problems, a servo press is currently used for press-fitting. A servo press is also commonly referred to as a servo press, which is a press that uses servo control technology to achieve precision control.

[0004] However, existing servo presses generally use ball screws to convert the rotational motion of the servo motor into linear motion. However, the servo presses using ball screws have poor bearing capacity and rigidity. When a larger pressure needs to be output, a larger servo press needs to be set up, which is not convenient for use in occasions with small space and large load requirements. In addition, the existing servo presses are provided with supporting copper sleeves between the two ends of the piston rod and the cylinder. On the one hand, the frictional heat generated is relatively large. On the other hand, both ends of the piston rod are supported by the copper sleeves without a certain amount of activity redundancy, resulting in the inability to balance the piston rod and the screw assembly, resulting in uneven operation or jamming due to different axes.

[0005] Therefore, a new solution needs to be proposed to solve this problem. Utility Model Content

[0006] In view of the deficiencies in the prior art, the purpose of the utility model is to provide a lightweight and high-rigidity servo press having the advantages of lightweight, high rigidity, good spatial adaptability, and smooth and stable operation.

[0007] The above-mentioned technical purpose of the utility model is achieved through the following technical solutions: a lightweight and high-rigidity servo press, comprising a turning seat and a rear cover fixed on the turning seat, a cylinder being fixed on the rear cover, a front cover being fixed on the end of the cylinder away from the rear cover, and also comprising a planetary roller screw, the planetary roller screw comprising a screw and a roller nut connected to the screw, the screw being rotatably connected in the cylinder, a driving assembly for driving the screw to rotate is arranged on the turning seat, a piston rod is axially slidably connected in the cylinder, the piston rod is a hollow cylindrical component, a copper sleeve is arranged in the front cover, the length of the copper sleeve is not less than the length of the front cover, one end of the piston rod extends out of the front cover along the copper sleeve, and the other end is sleeved and fixed on the roller nut, an anti-rotation key is embedded on the outside of the piston rod, and a sliding groove for axial sliding of the anti-rotation key is arranged on the inner wall of the cylinder.

[0008] In one embodiment, the front cover and the rear cover are both fixedly connected to the cylinder barrel by a first bolt, and the rear cover is fixedly connected to the turning seat by a second bolt.

[0009] In one embodiment, the driving assembly includes a servo reduction motor fixed on the turning seat, a driving wheel fixed on the output end of the servo reduction motor, a driven wheel rotatably connected in the turning seat, and a synchronous belt transmission-connected between the driving wheel and the driven wheel, and the screw rod extends into the turning seat along the rear cover and is fixedly connected to the driven wheel.

[0010] In one embodiment, the screw is rotatably connected in the rear cover via at least three ball bearings.

[0011] In one of the embodiments, the rear cover is provided with a first oil filling hole for filling oil into the screw rod, and the cylinder barrel is provided with a second oil filling hole for filling oil into the piston rod.

[0012] In one of the embodiments, an anti-collision pad is provided between the cylinder barrel and the rear cover, and the anti-collision pad is suitable for preventing the roller nut from being collided when it is retracted to the extreme position.

[0013] In one of the embodiments, a pressure sensor is provided on one end of the anti-collision pad close to the roller nut.

[0014] In one of the embodiments, a dust ring is provided on the piston rod inside the front cover and on a side of the copper sleeve away from the roller nut.

[0015] In summary, the utility model has the following beneficial effects:

[0016] 1. By using planetary roller screw as the transmission mechanism, compared with the traditional ball screw, the planetary roller screw has a more compact structure under the same load-bearing capacity and rigidity conditions, reducing the overall weight and size of the servo press, and can meet the press-fitting requirements in different scenarios. At the same time, the planetary roller screw structure has excellent load-bearing capacity and rigidity, so that the servo press can still maintain stable performance when outputting a large pressure, and has the advantage of high reliability;

[0017] 2. By setting a copper sleeve with a length not less than the length of the front cover only at one end of the piston rod, effective support for the piston rod is achieved, while avoiding the problems of increased friction and limited activity redundancy caused by the need to set copper sleeves at both ends in the traditional design. This method not only reduces the overall weight of the servo press, but also reduces frictional heat and extends the service life of the servo press. The other end of the piston rod is directly sleeved on the roller nut, giving the piston rod a certain amount of redundant space for activity. Even if the coaxiality between the piston rod and the roller nut fails to reach the optimal state, the piston rod can maintain good smoothness and stability during operation, effectively avoiding the occurrence of unsmoothness or jamming. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 A schematic structural diagram of a lightweight and high-rigidity servo press according to an embodiment of the present application;

[0019] Figure 2 A cross-sectional view of a lightweight and high-rigidity servo press according to an embodiment of the present application;

[0020] Figure 3 Schematic diagram of the internal structure of a lightweight and high-rigidity servo press according to an embodiment of the present application.

[0021] In the figure: 1. turning seat; 2. rear cover; 3. cylinder; 4. front cover; 5. first oil filling hole; 6. second oil filling hole; 7. servo reduction motor; 8. driving wheel; 9. driven wheel; 10. synchronous belt; 11. planetary roller screw; 111. screw rod; 112. roller nut; 12. dust ring; 13. ball bearing; 14. piston rod; 15. copper sleeve; 16. anti-rotation key; 17. anti-collision pad. DETAILED DESCRIPTION

[0022] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0023] like Figures 1 to 3As shown, the embodiment of the present application provides a lightweight high-rigidity servo press, including a turning seat 1 and a rear cover 2 fixed on the turning seat 1, a cylinder 3 is fixed on the rear cover 2, and a front cover 4 is fixed on the end of the cylinder 3 away from the rear cover 2, and also includes a planetary roller screw 11, the planetary roller screw 11 includes a screw 111 and a roller nut 112 connected to the screw 111, the screw 111 is rotatably connected in the cylinder 3, and the turning seat 1 is provided with a roller nut 112 for driving the screw 111. A rotating driving component, a piston rod 14 is axially slidably connected in the cylinder 3, the piston rod 14 is a hollow cylindrical component, a copper sleeve 15 is arranged in the front cover 4, the length of the copper sleeve 15 is not less than the length of the front cover 4, one end of the piston rod 14 extends out of the front cover 4 along the copper sleeve 15, and the other end is sleeved and fixed on the roller nut 112, an anti-rotation key 16 is embedded on the outside of the piston rod 14, and a slide groove for the axial sliding of the anti-rotation key 16 is arranged on the inner wall of the cylinder 3.

[0024] It should be noted that the planetary roller screw 11 adopts the existing technology, and its detailed structure is not described in detail in this embodiment.

[0025] When the above-mentioned servo press is working, the driving assembly drives the screw rod 111 to rotate, and the rotational motion of the screw rod 111 is converted into linear motion through the roller nut 112. Because there is a special spiral pair relationship between the roller nut 112 and the screw rod 111, the roller nut 112 can move linearly along the axial direction of the screw rod 111, thereby driving the piston rod 14 to perform linear telescopic motion.

[0026] In the above manner, by adopting the planetary roller screw 11 as the transmission mechanism, compared with the traditional ball screw 111, the planetary roller screw 11 has a more compact structure under the same load-bearing capacity and rigidity conditions, reducing the overall weight and size of the servo press, and being able to meet the pressing requirements in different scenarios. At the same time, the planetary roller screw 11 structure has excellent load-bearing capacity and rigidity, so that the servo press can still maintain stable performance when outputting a large pressure, and has the advantage of high reliability; by only arranging a copper sleeve 15 with a length not less than the length of the front cover 4 at one end of the piston rod 14, effective support of the piston rod 14 is achieved. The support is provided, and at the same time, the problems of increased friction and limited activity redundancy caused by the need to set copper sleeves 15 at both ends in the traditional design are avoided. This method not only reduces the overall weight of the servo press, but also reduces frictional heat and extends the service life of the servo press. The other end of the piston rod 14 is directly sleeved on the roller nut 112, giving the piston rod 14 a certain amount of redundant activity space. Even if the coaxiality between the piston rod 14 and the roller nut 112 fails to reach the optimal state, the piston rod 14 can maintain good smoothness and stability during operation, effectively avoiding the occurrence of unsmoothness or jamming.

[0027] In this embodiment, the front cover 4 and the rear cover 2 are fixedly connected to the cylinder 3 by a first bolt, and the rear cover 2 is fixedly connected to the turning seat 1 by a second bolt. The bolt connection method makes it more convenient and quick to assemble and disassemble the various components of the servo press.

[0028] In this embodiment, the driving assembly includes a servo reduction motor 7 fixed on the turning seat 1, a driving wheel 8 fixed on the output end of the servo reduction motor 7, a driven wheel 9 rotatably connected in the turning seat 1, and a synchronous belt 10 transmission-connected between the driving wheel 8 and the driven wheel 9, and the screw rod 111 extends into the turning seat 1 along the rear cover 2 and is fixedly connected to the driven wheel 9. A torque sensor is provided on the servo reduction motor 7, and the pressure value of the piston rod 14 is detected in real time by the torque sensor.

[0029] In the above manner, the synchronous belt 10 is used as a transmission medium to transmit the rotational motion of the driving wheel 8 to the driven wheel 9. During the transmission process, the synchronous belt 10 can maintain a constant transmission ratio and realize accurate transmission without slip.

[0030] In this embodiment, the screw rod 111 is rotatably connected to the rear cover 2 via at least three ball bearings 13. The support of multiple ball bearings 13 can effectively disperse the radial force and axial force generated by the screw rod 111 during rotation, reduce the vibration and deviation caused by uneven force, thereby improving the rotation accuracy of the screw rod 111. By increasing the number of ball bearings 13, the bearing capacity of the screw rod 111 support structure can be significantly improved.

[0031] In this embodiment, the rear cover 2 is provided with a first oil filling hole 5 for filling oil into the screw rod 111, and the cylinder 3 is provided with a second oil filling hole 6 for filling oil into the piston rod 14. Both the first oil filling hole 5 and the second oil filling hole 6 are provided with plungers.

[0032] In the above manner, oiling the screw rod 111 through the first oiling hole 5 can ensure that the screw rod 111 is fully lubricated during the rotation process, reduce the wear and heat generated by friction, and thus extend the service life of the screw rod 111. Similarly, oiling the piston rod 14 through the second oiling hole 6 can ensure that the piston rod 14 is lubricated as necessary during the sliding process.

[0033] In this embodiment, an anti-collision pad 17 is provided between the cylinder barrel 3 and the rear cover 2 , and the anti-collision pad 17 is suitable for preventing the roller nut 112 from being collided when it is retracted to the limit position.

[0034] In the above manner, during the operation of the servo press, the roller nut 112 may accidentally retract to the extreme position due to various reasons (such as overload, program error, etc.). If there is no protection of the anti-collision pad 17, the roller nut 112 directly collides with the cylinder 3 or the rear cover 2, which may cause serious mechanical damage and even affect the normal operation of the entire equipment. The presence of the anti-collision pad 17 effectively absorbs this impact energy and protects the equipment from impact damage.

[0035] In this embodiment, a pressure sensor is provided on one end of the anti-collision pad 17 close to the roller nut 112. The pressure sensor can monitor the contact pressure between the roller nut 112 and the anti-collision pad 17 in real time when the roller nut 112 is in the extreme position. When the pressure exceeds the preset safety threshold, the sensor will send a signal to the controller, and the controller will control the servo press to stop.

[0036] In this embodiment, a dust ring 12 is sleeved on the piston rod 14, which is located inside the front cover 4 and on the side of the copper sleeve 15 away from the roller nut 112. The dust ring 12 effectively prevents dust, impurities and other pollutants in the external environment from entering the interior of the front cover 4, especially preventing pollutants from contacting the sliding surfaces of the copper sleeve 15 and the piston rod 14, which is conducive to keeping the sliding surfaces clean and lubricated, and reducing wear and failure caused by pollutants.

[0037] The above is only a preferred embodiment of the present invention. The protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should also be regarded as the protection scope of the present invention.

Claims

1. A lightweight and high-rigidity servo press, comprising a turning seat (1) and a rear cover (2) fixed on the turning seat (1), a cylinder (3) fixed on the rear cover (2), and a front cover (4) fixed on the end of the cylinder (3) away from the rear cover (2), characterized in that: The invention also comprises a planetary roller screw (11), wherein the planetary roller screw (11) comprises a screw (111) and a roller nut (112) connected to the screw (111), wherein the screw (111) is rotatably connected in the cylinder barrel (3), and a driving assembly for driving the screw (111) to rotate is arranged on the turning seat (1), and a piston rod (14) is axially slidably connected in the cylinder barrel (3), and the piston rod (14) is a hollow cylindrical member, and a copper sleeve (15) is arranged in the front cover (4), and the length of the copper sleeve (15) is not less than the length of the front cover (4), one end of the piston rod (14) extends out of the front cover (4) along the copper sleeve (15), and the other end is sleeved and fixed on the roller nut (112), and an anti-rotation key (16) is embedded on the outside of the piston rod (14), and a slide groove for axial sliding of the anti-rotation key (16) is arranged on the inner wall of the cylinder barrel (3).

2. The lightweight and high-rigidity servo press according to claim 1, characterized in that: The front cover (4) and the rear cover (2) are both fixedly connected to the cylinder barrel (3) via a first bolt, and the rear cover (2) is fixedly connected to the turning seat (1) via a second bolt.

3. The lightweight and high-rigidity servo press according to claim 1, characterized in that: The driving assembly comprises a servo reduction motor (7) fixed on the turning seat (1), a driving wheel (8) fixed on the output end of the servo reduction motor (7), a driven wheel (9) rotatably connected in the turning seat (1), and a synchronous belt (10) transmission-connected between the driving wheel (8) and the driven wheel (9); the screw rod (111) extends into the turning seat (1) along the rear cover (2) and is fixedly connected to the driven wheel (9).

4. The lightweight and high-rigidity servo press according to claim 3, characterized in that: The screw rod (111) is rotatably connected in the rear cover (2) via at least three ball bearings (13).

5. The lightweight and high-rigidity servo press according to claim 1, characterized in that: The rear cover (2) is provided with a first oil injection hole (5) for injecting oil into the screw rod (111), and the cylinder barrel (3) is provided with a second oil injection hole (6) for injecting oil into the piston rod (14).

6. The lightweight and high-rigidity servo press according to claim 1, characterized in that: An anti-collision pad (17) is arranged between the cylinder barrel (3) and the rear cover (2), and the anti-collision pad (17) is suitable for preventing the roller nut (112) from being collided when it is retracted to an extreme position.

7. The lightweight and high-rigidity servo press according to claim 6, characterized in that: A pressure sensor is provided on one end of the anti-collision pad (17) close to the roller nut (112).

8. The lightweight and high-rigidity servo press according to claim 1, characterized in that: A dust ring (12) is sleeved on the piston rod (14) at a side of the copper sleeve (15) that is located inside the front cover (4) and away from the roller nut (112).

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