Die frame of hot forging die for aviation parts

Abstract

The invention relates to the technical field of hot forging die frames, in particular to an aviation part hot forging die frame which comprises a main supporting frame, a driving mechanism, a guiding assembly, a rotary opening and closing assembly and an air injection assembly. The guiding assembly comprises an annular frame and two side closing plates, the two side closing plates clamp the annular frame and are fixed to the side closing plates through bolts; a second guide groove is formed between the annular frame and the side closing plate. According to the forging and pressing device, through the arrangement of the rotary opening and closing assembly, the driving mechanism drives the rotary frame to rotate, the two mounting bases are driven to be circularly opened and closed when the rotary frame rotates, and the two mounting bases are close to each other to be closed, so that repeated forging and pressing shaping of a blank is achieved; and then the air injection assembly is matched to inject air to the upper side face of the blank and the die in the mounting base located at the upper end, so that oxide skin on the two faces of the two dies and the blank is removed in turn, and the influence of the oxide skin generated in the forging and pressing process on parts is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of hot forging die frames, in particular to a hot forging die frame for aviation parts. Background Art

[0002] The forging process performed above the metal recrystallization temperature is called hot forging, also known as hot die forging. During forging, the deformed metal flows violently and the contact time between the forging and the die is relatively long. Therefore, the mold material is required to have high thermal stability, high temperature strength and hardness, impact toughness, heat fatigue resistance and wear resistance and be easy to process. The hot forging mold with lighter workload can be made of low alloy steel. The hot forging process achieves precise control of the shape and size of metal parts by accurately controlling parameters such as temperature, pressure and deformation rate. The high temperature also helps to eliminate the residual stress and defects inside the material, improve the material density and mechanical properties of the parts, and the hot forging has a high surface finish without burrs and cracks. No additional machining is required to achieve high surface quality requirements. During hot forging, after the blank is heated to a high temperature, oxide scale is likely to appear on the surface during the hot end process. After the oxide scale is pressed into the part at the hot end, it is easy to cause defects in the part. Although the blank is descaled before being added to the forging equipment, new oxide scale will still be formed on the blank during the forging process. In addition, the existing forging die frame will continue to contact the lower die during forging, making it inconvenient to clean the new oxide scale formed on the lower surface of the blank during forging. A hot forging die frame for aviation parts is needed. Summary of the invention

[0003] The purpose of the present invention is to provide a hot forging die frame for aviation parts to solve the problems raised in the above background technology.

[0004] To achieve the above object, the present invention provides the following technical solutions: A hot forging die frame for aviation parts, comprising: A guide assembly, the guide assembly comprising an annular frame and two side clamping plates, the two side clamping plates clamp the annular frame and are fixed to the side clamping plates by bolts, and a second guide groove is provided between the annular frame and the side clamping plates; A main support frame, used to support and fix the annular frame; The rotary opening and closing assembly comprises a rotary frame, wherein two mounting seats are slidably connected in the rotary frame, wherein mounting slots for mounting the mold are provided in the mounting seats, and push rods are slidably connected at both ends of the rotary frame, wherein one end of the push rod is fixedly connected to the adjacent mounting seat, and the other end of the push rod is slidably connected to the second guide slot; An air jet assembly is located inside the annular frame, and includes two air jet nozzles, and the two air jet nozzles are respectively aligned with the mounting slots on the two mounting seats; The driving mechanism is used to drive the rotary frame to rotate.

[0005] Furthermore, both ends of the inner side wall of the rotating frame are fixedly connected with a fixing seat, four top corners of the two fixing seats are fixedly connected with sliding rods, the mounting seat is slidably sleeved with a plurality of sliding rods, and the push rod is slidably plugged with the fixing seat at the adjacent end.

[0006] Furthermore, the guide groove 2 includes closed parts arranged at both ends, and the guide groove 2 includes open parts arranged at both sides, the distance between the two closed parts is greater than the distance between the two open parts, and the arc angle of the open part is ninety degrees.

[0007] Furthermore, the other end of the push rod is fixedly connected to a sliding seat, the bottom end and the top end of the sliding seat are both rotatably connected to rollers, and the rollers are located in the second guide groove.

[0008] Furthermore, the driving mechanism includes a driving motor, a transmission shaft and a connecting frame, the transmission shaft is rotatably connected to the top position of the annular frame, the connecting frame is fixedly connected to one end face of the rotating frame, the transmission shaft and the connecting frame are transmission-connected, the driving motor is fixedly mounted on the main support frame, and the output end of the driving motor is transmission-connected to the other end of the transmission shaft.

[0009] Furthermore, an impact module is arranged inside the push rod, and the impact module is used to knock the mounting seat when the rotary frame rotates.

[0010] Furthermore, the impact module includes an impact rod, a long groove is provided on the outer side wall of the other end of the push rod, the impact rod is slidably connected with the adjacent push rod, the bottom end of the impact rod is fixedly connected with a limiting rod, a guide groove 1 is provided on one side wall of the side clamp, a wave section is provided on one side of the guide groove 1, and the other parts of the guide groove 1 except the wave section are arranged at equal intervals with the guide groove 2, the two ends of the limiting rod are slidably connected with the guide groove 1, the inner wall of the other end of the push rod is slidably connected with an impact block, a connecting spring is fixedly connected between the impact block and the other end of the impact rod, and the other end of the impact rod is fixedly connected with a core rod, and the core rod and the impact block are slidably connected.

[0011] The invention further comprises: an embedded groove is provided in the middle position of the inner wall of the annular frame, the bottom end of the annular frame is fixedly connected with an air inlet nozzle, the jet assembly also includes an outer air ring, the outer air ring is fixedly connected to the inner wall of the embedded groove, the air inlet nozzle is connected to the inner wall of the outer air ring, the inner wall of the outer air ring is slidably connected with the inner air ring, the inner walls on both sides of the inner air ring are fixedly connected with fixed ears, one end of the fixed ear is rotatably connected with a rotating seat, one end of the rotating seat is fixedly connected to an exhaust nozzle, one end of the exhaust nozzle is slidably sleeved with a ball head, both sides of the rotating frame are fixedly connected with ball sleeve seats, the ball head is movably sleeved with the ball sleeve seat on the adjacent side, and a hose is connected between one end of the exhaust nozzle and the inner wall of the inner air ring.

[0012] Furthermore, both ends of the inner wall of the inner air ring are fixedly connected with oblique guide frames, one side of the sliding seat is fixedly connected with a side bracket, and one end of the side bracket is slidably connected to the inner wall of the oblique guide frame.

[0013] Furthermore, the inclined guide frame is arranged to be inclined, and the distance between one end of the inclined guide frame and the adjacent sliding seat is smaller than the distance between the other end of the inclined guide frame and the ball sleeve seat.

[0014] Compared with the prior art, the present invention has the following beneficial effects: By setting the rotary opening and closing component, the driving mechanism drives the rotary frame to rotate, and the rotary frame drives the two mounting seats to open and close cyclically when rotating, and when the two mounting seats revolve to the upper and lower positions, the two mounting seats are separated from each other, and when the mounting seats revolve from the upper and lower positions to the left and right side positions, the two mounting seats are moved closer to each other and closed, so as to realize multiple forging and shaping of the blank, and the blank is turned over on both sides during forging, and then the upper side of the blank and the mold in the mounting seat at the upper end position of the jet assembly are jetted, so that the oxide scales on both sides of the two molds and the blank are removed in turn, reducing the influence of the oxide scales generated during the forging process on the parts; Through the setting of the impact module, when the push rod is deflected from the left side to the upper side, the push rod moves outward relative to the rotating frame, so that the two mounting seats are separated from each other. At the same time, when the limiting rod enters the wave section, the limiting rod drives the impact rod to move forward and backward along the axis of the push rod relative to the push rod, so that the impact rod drives the impact block to knock the corresponding mounting seat through the connecting spring, thereby facilitating the knocking of the mounting seat deflected to the upper position, and facilitating the separation of the mounting seat deflected to the upper position from the blank, thereby avoiding the blank from being stuck in the mounting seat. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the overall structure of the present invention; Figure 2 It is a schematic diagram of the overall front view structure of the present invention; Figure 3 It is a schematic diagram of the structure of the annular frame and the side plywood in the present invention; Figure 4 It is a schematic diagram of the internal structure of the guide component in the present invention; Figure 5 It is a schematic diagram of the side plywood structure in the present invention; Figure 6 yes Figure 5 A local enlarged view of point A; Figure 7 It is a schematic diagram of the structure of the jet assembly in the present invention; Figure 8 It is a schematic diagram of the structure of the rotary opening and closing component in the present invention.

[0016] In the figure: 100, main support frame; 200, driving mechanism; 210, connecting frame; 220, transmission shaft; 230, driving motor; 300, guide assembly; 310, annular frame; 311, embedded groove; 312, air inlet nozzle; 320, side plate; 321, guide groove 1; 322, wave section; 330, guide groove 2; 331, closing part; 332, opening part; 400, rotary opening and closing assembly; 410, rotary frame; 411, ball sleeve seat; 420, fixed seat; 421. Slide rod; 430. Mounting seat; 440. Push rod; 441. Sliding seat; 442. Roller; 443. Side bracket; 444. Long slot; 450. Impact module; 451. Impact rod; 452. Limit rod; 453. Core rod; 454. Connecting spring; 455. Impact block; 500. Jet assembly; 510. Outer air ring; 520. Inner air ring; 530. Fixing ear; 540. Rotating seat; 550. Exhaust nozzle; 560. Ball head; 570. Oblique guide frame. DETAILED DESCRIPTION

[0017] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0018] See also Figure 1-Figure 8 In an embodiment of the present invention, a hot forging die frame for aviation parts includes a main support frame 100, a driving mechanism 200, a guide assembly 300, a rotary opening and closing assembly 400 and an injection assembly 500. The guide assembly 300 includes an annular frame 310 and two side clamping plates 320. The two side clamping plates 320 clamp the annular frame 310 and are fixed to the side clamping plates 320 by bolts. A guide groove 230 is provided between the annular frame 310 and the side clamping plates 320. The main support frame 100 supports and fixes the annular frame 310. The rotary opening and closing assembly 400 includes a rotary frame 41 0, two mounting seats 430 are slidably connected inside the rotating frame 410, and mounting slots for mounting the mold are provided inside the mounting seats 430. Push rods 440 are slidably connected at both ends of the rotating frame 410, one end of the push rod 440 is fixedly connected to the adjacent mounting seat 430, and the other end of the push rod 440 is slidably connected to the guide groove 330. The jet assembly 500 is located inside the annular frame 310, and the jet assembly 500 includes two exhaust nozzles 550, which are respectively aligned with the mounting slot positions on the two mounting seats 430. The driving mechanism 200 is used to drive the rotating frame 410 to rotate.

[0019] Specifically, the upper die and the lower die of the mold are respectively installed in the mounting grooves of the mounting seat 430, and the driving mechanism 200 drives the rotating frame 410 to rotate. When the rotating frame 410 rotates, it drives the two push rods 440 to revolve. When the push rods 440 revolve, the guide groove 230 limits the other end of the push rods 440, so that the rotation of the rotating frame 410 drives the two mounting seats 430 to open and close cyclically, and when the two mounting seats 430 revolve to the upper and lower positions, the two mounting seats 430 are away from each other, and when the mounting seats 430 revolve from the upper and lower positions to the left and right side positions, the two mounting seats 430 are close to each other and closed, so as to realize multiple forging and shaping of the blank, and turn the blank on both sides during forging, and then cooperate with the jet assembly 500 to spray the upper side surface of the blank and the mold in the mounting seat 430 located at the upper end position, so as to remove the oxide scale on both sides of the two molds and the blank in turn, and reduce the influence of the oxide scale generated during the forging process on the parts.

[0020] Embodiment 1:

[0021] like Figure 5-Figure 8 As shown, in this embodiment, both ends of the inner side wall of the rotating frame 410 are fixedly connected with a fixed seat 420, and the four vertex corners of the two fixed seats 420 are fixedly connected with a sliding rod 421. The mounting seat 430 is slidably sleeved with multiple sliding rods 421, and the push rod 440 is slidably plugged with the fixed seat 420 at the adjacent end. The second guide groove 330 includes a closed portion 331 arranged at the two end positions, and the second guide groove 330 includes an open portion 332 arranged at the two side positions. The distance between the two closed portions 331 is greater than the distance between the two open portions 332. The arc angle of the open portion 332 is ninety degrees, and the push rod 440 is The other end is fixedly connected to a sliding seat 441, and the bottom and top of the sliding seat 441 are rotatably connected to rollers 442, and the rollers 442 are located in the guide groove 330. The driving mechanism 200 includes a driving motor 230, a transmission shaft 220 and a connecting frame 210. The transmission shaft 220 is rotatably connected to the top position of the annular frame 310, and the connecting frame 210 is fixedly connected to one end face of the rotating frame 410. The transmission shaft 220 and the connecting frame 210 are transmission-connected, and the driving motor 230 is fixedly mounted on the main support frame 100, and the output end of the driving motor 230 is transmission-connected to the other end of the transmission shaft 220.

[0022] In this embodiment, through the arrangement of the closing portion 331 and the opening portion 332, when the roller 442 at the other end of the push rod 440 is located at the opening portion 332, the two mounting seats 430 are in a closed state, when the other ends of the two push rods 440 are located on the closing portion 331, the two mounting seats 430 are in a separated state, and when the other ends of the two push rods 440 are located at the middle position of the closing portion 331, the distance between the two mounting seats 430 is at the maximum, so that when the rotating frame 410 rotates one circle, the two mounting seats 430 are opened and closed twice in a cycle, so that the mounting seats 430 are deflected to the upper position in turn and separated from the blank, thereby facilitating the jet cleaning of the model cavity of the mold.

[0023] like Figure 4-Figure 6 As shown, in this embodiment, an impact module 450 is arranged inside the push rod 440, and the impact module 450 is used to knock the mounting seat 430 when the rotating frame 410 rotates. The impact module 450 includes an impact rod 451, and a long groove 444 is provided on the outer wall of the other end of the push rod 440. The impact rod 451 is slidably plugged with the adjacent push rod 440, and the bottom end of the impact rod 451 is fixedly connected to the limit rod 452. A guide groove 321 is provided on one side wall of the side joint plate 320. The guide groove A wave section 322 is provided on one side of the first 321, and the other parts of the guide groove 321 except the wave section 322 are arranged at equal intervals with the guide groove 330, the two ends of the limit rod 452 are slidably connected to the guide groove 321, the other end of the push rod 440 is slidably connected to the inner wall with an impact block 455, a connecting spring 454 is fixedly connected between the impact block 455 and the other end of the impact rod 451, the other end of the impact rod 451 is fixedly connected to a core rod 453, and the core rod 453 and the impact block 455 are slidably plugged in.

[0024] During specific implementation, the wave section 322 is located at the upper left position of the guide groove 321. When the push rod 440 deflects from the left side to the upper side, the push rod 440 moves outward relative to the rotating frame 410, so that the two mounting seats 430 are separated from each other. At the same time, when the limiting rod 452 enters the wave section 322, the limiting rod 452 drives the impact rod 451 to move forward and backward along the axis of the push rod 440 relative to the push rod 440, so that the impact rod 451 drives the impact block 455 to knock the corresponding mounting seat 430 through the connecting spring 454, thereby facilitating the knocking of the mounting seat 430 deflected to the upper position, and facilitating the separation of the mounting seat 430 deflected to the upper position from the blank, thereby avoiding the blank from being stuck in the mounting seat 430.

[0025] Embodiment 2:

[0026] like Figure 4-Figure 8As shown, in this embodiment, an inner wall of the annular frame 310 is provided with an embedded groove 311 in the middle position, and the bottom end of the annular frame 310 is fixedly connected with an air inlet nozzle 312, and the jet assembly 500 also includes an outer air ring 510, the outer air ring 510 is fixedly connected to the inner wall of the embedded groove 311, the air inlet nozzle 312 is connected to the inner wall of the outer air ring 510, the inner wall of the outer air ring 510 is slidably connected with the inner air ring 520, and the inner walls of both sides of the inner air ring 520 are fixedly connected with fixed ears 530, one end of the fixed ear 530 is rotatably connected with a rotating seat 540, one end of the rotating seat 540 is fixedly connected with the exhaust nozzle 550, and one end of the exhaust nozzle 550 is slidably connected to the inner wall of the outer air ring 510. A ball head 560 is movablely sleeved, and ball sleeve seats 411 are fixedly connected on both sides of the rotating frame 410. The ball head 560 is movably sleeved with the ball sleeve seat 411 on the adjacent side. A hose is connected between one end of the exhaust nozzle 550 and the inner wall of the inner air ring 520. Both ends of the inner wall of the inner air ring 520 are fixedly connected with inclined guide frames 570. A side bracket 443 is fixedly connected to one side of the sliding seat 441. One end of the side bracket 443 is slidably connected to the inner wall of the inclined guide frame 570. The inclined guide frame 570 is inclined, and the distance between one end of the inclined guide frame 570 and the adjacent sliding seat 441 is smaller than the distance between the other end of the inclined guide frame 570 and the ball sleeve seat 411.

[0027] In a specific implementation, the outer air ring 510 and the inner air ring 520 are arranged to facilitate the jet assembly 500 to follow the revolution of the rotating frame 410, and the external gas is introduced into the exhaust nozzle 550 through the air inlet nozzle 312. At the same time, through the arrangement of the inclined guide frame 570, when the other end of the push rod 440 moves toward the rotating frame 410, the two mounting seats 430 move closer to each other, and at the same time, the sliding seat 441 drives the inner air ring 520 to rotate through the side bracket 443 and the inclined guide frame 570, and the sliding seat 441 moves away from the inner air ring 520. When the ring 520 moves, the inner air ring 520 is driven to rotate relative to the rotating frame 410 through the side bracket 443 and the inclined guide frame 570. When the inner air ring 520 rotates relative to the rotating frame 410, the exhaust nozzle 550 is driven to rotate through the fixed ear 530, so as to adjust the angle of the exhaust nozzle 550, so that when the mounting seat 430 opens and closes, it is convenient for the exhaust nozzle 550 to follow the movement of the mounting seat 430 to adjust the angle, so that the corresponding exhaust nozzle 550 is always aligned with the mounting groove on the mounting seat 430.

[0028] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

[0029] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A hot forging die frame for aviation parts, characterized in that: include A guide assembly (300), the guide assembly (300) comprising an annular frame (310) and two side clamping plates (320), the two side clamping plates (320) clamp the annular frame (310) and are fixed to the side clamping plates (320) by bolts, and a second guide groove (330) is provided between the annular frame (310) and the side clamping plates (320); A main support frame (100) supports and fixes the annular frame (310); The rotary opening and closing assembly (400) comprises a rotary frame (410), wherein two mounting seats (430) are slidably connected inside the rotary frame (410), wherein mounting grooves for mounting a mold are provided inside the mounting seats (430), and push rods (440) are slidably connected at both ends of the rotary frame (410), wherein one end of the push rod (440) is fixedly connected to an adjacent mounting seat (430), and the other end of the push rod (440) is slidably connected to a second guide groove (330); An air jet assembly (500) is located inside the annular frame (310), and the air jet assembly (500) includes two air exhaust nozzles (550), and the two air exhaust nozzles (550) are respectively aligned with the installation slots on the two installation seats (430); The driving mechanism (200) is used to drive the rotating frame (410) to rotate.

2. The hot forging die frame for aviation parts according to claim 1, characterized in that: Both ends of the inner side wall of the rotating frame (410) are fixedly connected with a fixing seat (420), and four top corners of the two fixing seats (420) are fixedly connected with a sliding rod (421). The mounting seat (430) is slidably sleeved with the plurality of sliding rods (421), and the push rod (440) is slidably plugged with the fixing seat (420) at the adjacent end.

3. The hot forging die frame for aviation parts according to claim 2, characterized in that: The second guide groove (330) comprises closed portions (331) arranged at two end positions, and the second guide groove (330) comprises open portions (332) arranged at two side positions, the distance between the two closed portions (331) is greater than the distance between the two open portions (332), and the arc angle of the open portion (332) is ninety degrees.

4. The hot forging die frame for aviation parts according to claim 3, characterized in that: The other end of the push rod (440) is fixedly connected to a sliding seat (441), and the bottom and top ends of the sliding seat (441) are rotatably connected to rollers (442), and the rollers (442) are located in the second guide groove (330).

5. The hot forging die frame for aviation parts according to claim 4, characterized in that: The driving mechanism (200) comprises a driving motor (230), a transmission shaft (220) and a connecting frame (210); the transmission shaft (220) is rotatably connected to the top end of the annular frame (310); the connecting frame (210) is fixedly connected to one end surface of the rotating frame (410); the transmission shaft (220) and the connecting frame (210) are in transmission connection; the driving motor (230) is fixedly mounted on the main support frame (100); and the output end of the driving motor (230) is in transmission connection with the other end of the transmission shaft (220).

6. The hot forging die frame for aviation parts according to claim 4, characterized in that: An impact module (450) is arranged inside the push rod (440), and the impact module (450) is used to strike the mounting seat (430) when the rotating frame (410) rotates.

7. The hot forging die frame for aviation parts according to claim 6, characterized in that: The impact module (450) comprises an impact rod (451), an outer side wall of the other end of the push rod (440) is provided with a long groove (444), the impact rod (451) is slidably plugged with the adjacent push rod (440), the bottom end of the impact rod (451) is fixedly connected to a limit rod (452), a guide groove 1 (321) is provided on one side wall of the side joint plate (320), a wave section (322) is provided on one side of the guide groove 1 (321), and the guide groove 1 (321) has a wave section (322) on the other side. The other parts of the push rod (440) are arranged at equal intervals with the guide groove 1 (322), the two ends of the limit rod (452) are slidably connected to the guide groove 1 (321), the inner wall of the other end of the push rod (440) is slidably connected to an impact block (455), a connecting spring (454) is fixedly connected between the impact block (455) and the other end of the impact rod (451), the other end of the impact rod (451) is fixedly connected to a core rod (453), and the core rod (453) and the impact block (455) are slidably plugged together.

8. The hot forging die frame for aviation parts according to claim 6, characterized in that: An embedded groove (311) is provided in the middle of the inner wall of the annular frame (310), and an air inlet nozzle (312) is fixedly connected to the bottom end of the annular frame (310). The jet assembly (500) further comprises an outer air ring (510), the outer air ring (510) is fixedly connected to the inner wall of the embedded groove (311), the air inlet nozzle (312) is connected to the inner wall of the outer air ring (510), the inner wall of the outer air ring (510) is slidably connected to the inner air ring (520), and the inner walls on both sides of the inner air ring (520) are fixedly connected to the inner wall of the outer air ring (510). A fixing ear (530) is connected, one end of the fixing ear (530) is rotatably connected to a rotating seat (540), one end of the rotating seat (540) is fixedly connected to an exhaust nozzle (550), one end of the exhaust nozzle (550) is slidably sleeved with a ball head (560), both sides of the rotating frame (410) are fixedly connected to ball sleeve seats (411), the ball head (560) is movably sleeved with the ball sleeve seat (411) on the adjacent side, and a hose is connected between one end of the exhaust nozzle (550) and the inner wall of the inner air ring (520).

9. The hot forging die frame for aviation parts according to claim 8, characterized in that: An inclined guide frame (570) is fixedly connected to both ends of the inner wall of the inner air ring (520), a side bracket (443) is fixedly connected to one side of the sliding seat (441), and one end of the side bracket (443) is slidably connected to the inner wall of the inclined guide frame (570).

10. The hot forging die frame for aviation parts according to claim 9, characterized in that: The inclined guide frame (570) is arranged to be inclined, and the distance between one end of the inclined guide frame (570) and the adjacent sliding seat (441) is smaller than the distance between the other end of the inclined guide frame (570) and the ball sleeve seat (411).

Images