Press fitting device for engine cylinder cover seat ring

Abstract

The invention relates to an engine cylinder cover seat ring press-fitting device which comprises a press-fitting seat and a rack fixed above the press-fitting seat, the top of the rack is provided with a pressing head driven by a hydraulic mechanism, the top of the press-fitting seat is provided with a movable clamp used for positioning a cylinder cover, and the movable clamp is provided with a pressing head driven by a hydraulic mechanism. And a feeding mechanism used for providing a seat ring is arranged on the back face of the rack. According to the press-fitting device for the engine cylinder cover seat ring, auxiliary press-fitting is carried out through a semi-positioning sleeve auxiliary mechanism, the seat ring can be accurately positioned, an elastic air bag ring and an abutting piece are evenly expanded after being inflated, scratching of the inner wall of the seat ring caused by rigid contact is avoided, meanwhile, the press-fitting device adapts to the characteristics of fragile materials after liquid nitrogen low-temperature treatment, and the service life of the seat ring is prolonged. The length of the positioning rod and the bead ring is consistent with the height of the seat ring, the bead ring is combined to limit the expansion range of the air bag, the radial positioning precision of the seat ring is ensured, press-fitting deflection is prevented, the positions of the sleeves do not need to be manually adjusted one by one, and the press-fitting effect is higher and more stable.

Description

Technical Field

[0001] The present invention relates to the technical field of cylinder head pressing, and specifically to a pressing device for an engine cylinder head seat ring. Background Art

[0002] The pressing of an engine cylinder head seat ring (such as a valve seat ring) is a key process in engine assembly, directly affecting valve sealing performance, heat dissipation performance, and engine life. Traditional pressing processes mostly use a hydraulic head to directly apply pressure, and there are the following problems:

[0003] Insufficient positioning accuracy: The coaxiality deviation between the seat ring and the cylinder hole easily causes tilting during pressing, resulting in poor sealing or valve movement interference.

[0004] Damage to shrink fit: The seat ring after being frozen with liquid nitrogen is prone to cracking during pressing due to low-temperature brittleness, and traditional rigid jigs cannot effectively protect it.

[0005] Low degree of automation: Manual feeding and positioning are inefficient, and it is difficult to ensure the consistency of batch production.

[0006] Poor control of pressing springback: After the seat ring is pressed in, it is prone to springback due to the elasticity of the material, and repeated adjustments are required, affecting the assembly efficiency.

[0007] During the pressing process of the engine seat ring, in order to avoid local stress concentration and prevent surface damage, a sleeve is mostly used to assist in pressing. However, the existing sleeves are basically non-fixed, and manual holding and alignment are required for pressing, which may cause errors. When effective alignment cannot be achieved, it is easy to damage the cylinder head and the seat ring. Summary of the Invention

[0008] In view of the deficiencies of the prior art, the present invention provides a pressing device for an engine cylinder head seat ring, which solves the above-mentioned problems.

[0009] To achieve the above objectives, the present invention is realized through the following technical solutions: A pressing device for an engine cylinder head seat ring, including a pressing seat and a frame fixed above the pressing seat. A pressing head driven by a hydraulic mechanism is provided at the top of the frame. A moving jig for positioning the cylinder head is provided at the top of the pressing seat. A feeding mechanism for providing the seat ring is provided on the back of the frame. A sleeve assisting structure for pressing the seat ring is provided on the surface of the frame and located below the pressing head;

[0010] The sleeve auxiliary structure includes a lifting plate slidably arranged in the inner cavity of the frame through a sliding groove. A connecting plate is fixedly connected to the surface of the lifting plate. A fixed cylinder is fixedly connected to the inner cavity of the connecting plate. A lifting rod that penetrates and extends downward is slidably connected to the top of the fixed cylinder. A pressing head is fixedly connected to the bottom of the lifting rod. A positioning component for positioning the seat ring is arranged at the bottom of the pressing head. The positioning component includes a positioning rod fixed below the pressing head. An elastic airbag ring is wrapped around the outer surface of the positioning rod. A plurality of abutting pieces are fixedly connected to the outer side of the elastic airbag ring. A top plate is fixedly connected to the top end of the lifting rod. A return spring is sleeved on the surface of the lifting rod between the top plate and the fixed cylinder. The two ends of the return spring abut against the top plate and the fixed cylinder respectively. A lifting spring fixedly connected to the inner cavity of the sliding groove is fixedly connected to the top of the lifting plate. When in use, after the seat ring is provided by the feeding mechanism, at this time, the pressing head descends to press the top plate. The top plate drives the lifting rod to move downward in the fixed cylinder. At this time, both the return spring and the lifting spring are stretched downward. Then the pressing head descends to press on the top of the seat ring. The positioning rod is inserted into the inner cavity of the seat ring. Then, an external air source supplies air to the elastic airbag ring. The elastic airbag ring expands and drives the abutting pieces on the side to press the inner cavity of the seat ring. Then the pressing head rises by 2 cm. At this time, driven by the reset of the return spring and the lifting spring, the pressing head rebounds, driving the seat ring to rise from the feeding mechanism. Then the feeding mechanism is retracted. At this time, the pressing head continues to press down. The positioned cylinder head is moved to be aligned below the seat ring through a moving fixture. The pressing head presses the seat ring into the inside of the cylinder head. After entering the cylinder head, at this time, the elastic airbag ring deflates and contracts, no longer applying force to the seat ring. At this time, the seat ring is already positioned in the inner cavity of the cylinder head. Then the pressing head presses down for positioning to make it completely compacted.

[0011] As a further solution of the present invention: A steel wire ring is arranged on the outer side of the elastic airbag ring. The periphery of the elastic airbag ring is restricted by the steel wire ring to make it expand evenly.

[0012] As a further solution of the present invention: The abutting pieces are made of low-temperature resistant material, which can effectively resist the seat ring after being frozen by liquid nitrogen.

[0013] As a further solution of the present invention: The length of the positioning rod is the same as the height of the seat ring. The seat ring is effectively positioned by the positioning rod to ensure that its positioning effect will not be affected when it is accurately press-fitted.

[0014] As a further solution of the present invention: The feeding mechanism includes a rotating shaft rotatably arranged on the back of the frame and driven by a motor, and a liquid nitrogen box fixed on the back of the frame. Four symmetrically arranged lifting cylinders are fixedly connected to the side of the rotating shaft. The bottom end of the piston rod of the lifting cylinder is fixedly connected with a seat ring placing plate. The seat ring placing plate is provided with a placing groove adapted to the seat ring. A hollow groove adapted to the rotation track of the seat ring placing plate is provided on the surface of the frame. When in use, the seat ring is placed above the right seat ring placing plate, then the rotating shaft rotates to drive the lifting cylinder to rotate, driving the seat ring placing plate with the seat ring placed thereon to descend into the liquid nitrogen box to cool the seat ring and make it shrink. Then the lifting cylinder drives the seat ring placing plate to rise. After taking out the seat ring, the rotating shaft continues to rotate to drive the seat ring to rotate through the hollow groove and enter under the sleeve auxiliary mechanism for press-fitting.

[0015] As a further solution of the present invention: During processing, the pressing head, the extrusion head, the positioning rod, the seat ring and the cylinder head cylinder hole are on the same center line.

[0016] The present invention has the following beneficial effects compared with the prior art:

[0017] High-precision positioning and anti-damage

[0018] Elastic airbag ring and abutting piece: After inflation, it expands uniformly, avoiding scratching the inner wall of the seat ring caused by rigid contact, and at the same time adapting to the brittle material characteristics after low-temperature treatment with liquid nitrogen.

[0019] Positioning rod and wire ring: The length is the same as the height of the seat ring. Combining with the wire ring to limit the expansion range of the airbag, ensuring the radial positioning accuracy of the seat ring and preventing press-fitting skew.

[0020] Improved low-temperature adaptability

[0021] Low-temperature resistant abutting piece: Made of polytetrafluoroethylene or special alloy material, resistant to the liquid nitrogen environment of -196°C, avoiding low-temperature brittle fracture.

[0022] Automation of liquid nitrogen cooling: Through the rotating shaft and the lifting cylinder, batch cooling and transfer of the seat ring are realized, reducing manual intervention and improving efficiency.

[0023] Press-fitting springback control

[0024] Dual spring reset system: When the pressing head rises for the first time, the spring return force drives the seat ring to rise stably, avoiding position deviation caused by the elasticity of the material.

[0025] Automation and efficiency optimization

[0026] Rotary feeding mechanism: The four-station lifting cylinder cooperates with the hollow groove to realize continuous cooling, transfer and press-fitting of the seat ring, and the single-cycle time is shortened by 30%.

[0027] Moving fixture: quickly locates the cylinder head, seamlessly connects with the press-fitting process, and is suitable for flexible production of multiple engine models.

[0028] Guarantee of quality consistency

[0029] Center line alignment design: all key components are coaxially arranged, with the tolerance controlled within 0.05 mm to avoid individual differences in mass production.

[0030] Auxiliary press-fitting is carried out through a semi-positioning sleeve auxiliary mechanism, which can accurately position the seat ring. The elastic airbag ring and the abutting piece: after inflation, they expand evenly, avoiding scratches on the inner wall of the seat ring caused by rigid contact. At the same time, they adapt to the brittle material characteristics after cryogenic treatment with liquid nitrogen. The positioning rod and the wire ring: the length is the same as the height of the seat ring, and the wire ring is combined to limit the expansion range of the airbag, ensuring the radial positioning accuracy of the seat ring, preventing press-fitting skew, and moreover, there is no need to manually adjust the position of each sleeve one by one, and the press-fitting effect is higher and more stable. Description of the drawings

[0031] Figure 1 It is a schematic structural diagram of the present invention;

[0032] Figure 2 For the present invention Figure 1 The partial enlarged view at A in it;

[0033] Figure 3 It is a schematic structural diagram of the feeding mechanism of the present invention;

[0034] Figure 4 It is the top view of the structure of the positioning rod of the present invention.

[0035] In the figure: 1, press-fitting seat; 2, hydraulic mechanism; 3, press head; 4, frame; 5, moving fixture; 6, sliding groove; 7, lifting plate; 8, connecting plate; 9, lifting spring; 10, lifting rod; 11, top plate; 12, return spring; 13, fixed cylinder; 14, extrusion head; 15, abutting piece; 16, positioning rod; 17, elastic airbag ring; 18, hollow groove; 19, seat ring placement plate; 20, rotating shaft; 21, lifting cylinder; 22, liquid nitrogen box; 23, placement groove. Specific embodiments

[0036] To further elaborate on the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the following combines the drawings and preferred embodiments to describe in detail the specific embodiments, structures, features and effects according to the present invention as follows.

[0037] Please refer to Figures 1-4, the present invention provides a technical solution: a press-fitting device for an engine cylinder head seat ring, which includes a press-fitting seat 1 and a frame 4 fixed above the press-fitting seat 1. At the top of the frame 4, there is a press head 3 driven by a hydraulic mechanism 2. At the top of the press-fitting seat 1, there is a moving fixture 5 for positioning the cylinder head. On the back of the frame 4, there is a feeding mechanism for providing the seat ring. On the surface of the frame 4, there is a sleeve auxiliary structure located below the press head 3 for press-fitting the seat ring;

[0038] The sleeve auxiliary structure includes a lifting plate 7 slidably arranged in the inner cavity of the frame 4 through a sliding groove 6. On the surface of the lifting plate 7, there is a connecting plate 8 fixedly connected. In the inner cavity of the connecting plate 8, there is a fixed cylinder 13 fixedly connected. At the top of the fixed cylinder 13, there is a lifting rod 10 slidably connected and extending downward. At the bottom of the lifting rod 10, there is an extrusion head 14 fixedly connected. At the bottom of the extrusion head 14, there is a positioning component for positioning the seat ring. The positioning component includes a positioning rod 16 fixed below the extrusion head 14. The outer surface of the positioning rod 16 is covered with an elastic airbag ring 17. On the outer side of the elastic airbag ring 17, there are a plurality of abutting pieces 15 fixedly connected. At the top end of the lifting rod 10, there is a top plate 11 fixedly connected. On the surface of the lifting rod 10 between the top plate 11 and the fixed cylinder 13, there is a return spring 12 sleeved. The two ends of the return spring 12 are respectively abutted against the top plate 11 and the fixed cylinder 13. At the top of the lifting plate 7, there is a lifting spring 9 fixedly connected to the inner cavity of the sliding groove 6. When in use, after the seat ring is provided by the feeding mechanism, at this time, the press head 3 descends to squeeze the top plate 11. The top plate 11 drives the lifting rod 10 to move downward in the fixed cylinder 13. At this time, both the return spring 12 and the lifting spring 9 are stretched downward. Then the extrusion head 14 descends to squeeze on the top of the seat ring. The positioning rod 16 is inserted into the inner cavity of the seat ring. Then, an external air source is used to supply air to the elastic airbag ring 17. The elastic airbag ring 17 expands to drive the side abutting pieces 15 to squeeze the inner cavity of the seat ring. Then the press head 3 rises by 2 cm. At this time, driven by the reset of the return spring 12 and the lifting spring 9, the extrusion head 14 rebounds, driving the seat ring to rise from the feeding mechanism. Then the feeding mechanism is retracted. At this time, the press head 3 continues to press down. The positioned cylinder head is moved by the moving fixture 5 to be aligned below the seat ring. The extrusion head 14 squeezes the seat ring into the inside of the cylinder head. After entering the cylinder head, at this time, the elastic airbag ring 17 deflates and contracts, no longer applying force to the seat ring. At this time, the seat ring is already positioned in the inner cavity of the cylinder head. Then the extrusion head 14 presses down for positioning to make it completely compacted.

[0039] There is a steel wire ring on the outer side of the elastic airbag ring 17 to limit the periphery of the elastic airbag ring 17, so that it expands evenly.

[0040] The abutting pieces 15 are made of low-temperature resistant materials, which can effectively resist the seat ring after being frozen by liquid nitrogen.

[0041] The length of the positioning rod 16 is the same as the height of the seat ring. Then, the seat ring is effectively positioned by the positioning rod 16 to ensure that its positioning effect will not be affected when it is accurately press-fitted.

[0042] The feeding mechanism includes a rotating shaft 20 rotatably arranged on the back of the frame 4 and driven by a motor, and a liquid nitrogen box 22 fixed on the back of the frame 4. Four symmetrically arranged lifting cylinders 21 are fixedly connected to the side of the rotating shaft 20. The bottom end of the piston rod of the lifting cylinder 21 is fixedly connected with a seat ring placement plate 19. The seat ring placement plate 19 is provided with a placement groove 23 adapted to the seat ring. A hollow groove 18 adapted to the rotation track of the seat ring placement plate 19 is provided on the surface of the frame 4. When in use, the seat ring is placed above the right seat ring placement plate 19, and then the rotating shaft 20 rotates to drive the lifting cylinder 21 to rotate, driving the seat ring placement plate 19 with the seat ring placed thereon to descend into the liquid nitrogen box 22 to cool the seat ring and make it contract. Then, the lifting cylinder 21 drives the seat ring placement plate 19 to rise. After taking out the seat ring, the rotating shaft 20 continues to rotate to drive the seat ring to rotate through the hollow groove 18 and enter below the sleeve auxiliary mechanism for press-fitting.

[0043] During processing, the press head 3, the extrusion head 14, the positioning rod 16, the seat ring, and the cylinder head cylinder hole are on the same center line.

[0044] High-precision positioning and anti-damage

[0045] The elastic airbag ring 17 and the abutting piece 15: After inflation, they expand uniformly to avoid scratching the inner wall of the seat ring caused by rigid contact, and at the same time adapt to the brittle material characteristics after low-temperature treatment with liquid nitrogen.

[0046] The positioning rod 16 and the wire ring: The length is the same as the height of the seat ring. Combining with the wire ring to limit the expansion range of the airbag, ensuring the radial positioning accuracy of the seat ring and preventing press-fitting skew.

[0047] Improved low-temperature adaptability

[0048] The low-temperature resistant abutting piece 15: Made of polytetrafluoroethylene PTFE or special alloy material, it can withstand the liquid nitrogen environment of -196°C and avoid brittle fracture at low temperature.

[0049] Automation of liquid nitrogen cooling: The batch cooling and transfer of the seat ring are realized through the rotating shaft 20 and the lifting cylinder 21, reducing manual intervention and improving efficiency.

[0050] Press-fitting springback control

[0051] Dual-spring reset system: When the press head 3 rises for the first time, the spring return force drives the seat ring to rise stably, avoiding position deviation caused by the elasticity of the material.

[0052] Automation and efficiency optimization

[0053] Rotary loading mechanism: The four-station lifting cylinder 21 cooperates with the hollow groove 18 to achieve continuous cooling, transfer, and press-fitting of the seat ring, shortening the single-cycle time by 30%.

[0054] Moving fixture 5: Quickly position the cylinder head, seamlessly connect with the press-fitting process, and is suitable for flexible production of multiple engine models.

[0055] Guarantee of quality consistency

[0056] Center line alignment design: All key components, such as the punch, extrusion head, seat ring, and cylinder hole, are coaxially arranged, with the tolerance controlled within 0.05 mm to avoid individual differences in mass production.

[0057] The above are only the preferred embodiments of the present invention, and do not impose any form of limitation on the present invention. Although the present invention has been disclosed above with preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some changes or modifications to the equivalent embodiments by using the disclosed technical content within the scope of the technical solution of the present invention. However, as long as it does not depart from the content of the technical solution of the present invention, any brief modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A press-fitting device for an engine cylinder head seat ring, comprising a press-fitting seat (1) and a frame (4) fixed above the press-fitting seat (1), wherein a press head (3) driven by a hydraulic mechanism (2) is arranged on the top of the frame (4), and characterized in that: The top of the press-fitting seat (1) is provided with a movable fixture (5) for positioning the cylinder head, the back of the frame (4) is provided with a feeding mechanism for providing the seat ring, and the surface of the frame (4) is provided with a sleeve auxiliary structure located below the pressing head (3) for press-fitting the seat ring; The sleeve auxiliary structure comprises a lifting plate (7) slidably arranged in the inner cavity of the frame (4) through a sliding groove (6); a connecting plate (8) is fixedly connected to the surface of the lifting plate (7); a fixing cylinder (13) is fixedly connected to the inner cavity of the connecting plate (8); a lifting rod (10) penetrating and extending to the bottom is slidably connected to the top of the fixing cylinder (13); an extrusion head (14) is fixedly connected to the bottom of the lifting rod (10); a positioning assembly for positioning the seat ring is arranged at the bottom of the extrusion head (14); the positioning assembly comprises a positioning rod ( 16), the outer surface of the positioning rod (16) is covered with an elastic airbag ring (17), the outer side of the elastic airbag ring (17) is fixedly connected with a plurality of abutment plates (15), the top end of the lifting rod (10) is fixedly connected with a top plate (11), the surface of the lifting rod (10) located between the top plate (11) and the fixed tube (13) is sleeved with a return spring (12), the two ends of the return spring (12) are respectively abutted with the top plate (11) and the fixed tube (13), and the top of the lifting plate (7) is fixedly connected with a lifting spring (9) fixedly connected to the inner cavity of the sliding groove (6).

2. The press-fitting device for the engine cylinder head seat ring according to claim 1, characterized in that: A wire ring is arranged on the outer side of the elastic airbag ring (17).

3. The press-fitting device for the engine cylinder head seat ring according to claim 1, characterized in that: The contact piece (15) is made of low-temperature resistant material.

4. The press-fitting device for the engine cylinder head seat ring according to claim 1, characterized in that: The length of the positioning rod (16) is the same as the height of the seat ring.

5. The press-fitting device for the engine cylinder head seat ring according to claim 1, characterized in that: The feeding mechanism comprises a rotating shaft (20) rotatably arranged on the back of a frame (4) and driven by a motor, and a liquid nitrogen box (22) fixed on the back of the frame (4); four symmetrically arranged lifting cylinders (21) are fixedly connected to the side of the rotating shaft (20); the bottom end of the piston rod of the lifting cylinder (21) is fixedly connected to a seat ring placement plate (19); the seat ring placement plate (19) is provided with a placement groove (23) adapted to the seat ring; and the surface of the frame (4) is provided with a hollow groove (18) adapted to the rotation trajectory of the seat ring placement plate (19).

6. The press-fitting device for the engine cylinder head seat ring according to claim 1, characterized in that: During processing, the pressure head (3), the extrusion head (14), the positioning rod (16), the seat ring and the cylinder hole of the cylinder head are located on the same center line.

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