Automatic transmission parking actuator

Abstract

The present invention discloses an automatic transmission parking actuator, comprising a parking ratchet wheel engaging one end of a parking pawl, a parking pawl pin passing through the parking pawl, a pawl return torsion spring sleeved on the parking pawl pin, one end of the pawl return torsion spring connected to the parking pawl, one end of a push rod assembly engaging the other end of the parking pawl, the other end of the push rod assembly connected to a power transmission mechanism, one end of an arm fixed to a main body, a through hole formed between two adjacent arms, one end of a limiting portion fixed to the main body, a guide groove formed between two adjacent limiting portions and the main body, the other end of the limiting portion provided with a matching portion, the other end of the parking pawl engaging the matching portion, one end of the push rod assembly passing through the through hole and entering the guide groove, one end of the push rod assembly engaging the other end of the parking pawl; a compression spring assembly having one end engaging with the parking pawl, the other end of the compression spring assembly engaging with a baffle. The present invention has the advantages of higher safety and better applicability.

Description

Technical Field

[0001] The present invention relates to the technical field of automobile transmissions, and in particular to a parking actuator for an automatic transmission. Background Art

[0002] The automotive industry is developing rapidly, but safety and reliability are always the most important fundamental requirements, which naturally includes the safety and reliability of automatic transmission parking mechanisms. At the same time, with the acceleration of market product upgrades, platform-based product development is a necessary condition for saving cycles and ensuring sufficient verification. High performance and low cost are the key to companies gaining an advantage in the competition. Figure 1 As shown, it mainly includes a parking ratchet, a parking pawl, a parking pawl pin, a parking pawl return spring, a push rod assembly, a power transmission mechanism, etc. When parking, the power transmission mechanism rotates, driving the push rod assembly to move axially, pressing the parking pawl downward, so that the end of the parking pawl is inserted into the rectangular groove of the parking ratchet to complete the parking action.

[0003] The parking actuator of the prior art has the following defects:

[0004] (1) There is no redundant structural design. Once the parking pawl return torsion spring fails, the parking pawl will fall and collide with the parking ratchet.

[0005] (2) When shifting out of P gear, the impact force of the parking pawl acts directly on the push rod assembly.

[0006] (3) There is no locking structure, which limits the type of drive source (motor) selection.

[0007] (4) The layout is not flexible and the matching adaptability is not strong. Summary of the Invention

[0008] The present invention provides a parking actuator for an automatic transmission with higher safety and better applicability.

[0009] The technical solutions to the above problems are as follows:

[0010] The automatic transmission parking actuator includes a parking ratchet, a parking pawl, a parking pawl pin, a pawl return torsion spring, a push rod assembly, and a power transmission mechanism. The parking ratchet cooperates with one end of the parking pawl, the parking pawl pin passes through the parking pawl, the pawl return torsion spring is sleeved on the parking pawl pin, one end of the pawl return torsion spring is connected to the parking pawl, one end of the push rod assembly cooperates with the other end of the parking pawl, and the other end of the push rod assembly is connected to the power transmission mechanism. It also includes:

[0011] The parking guide plate includes a main body, at least two arms, and at least two limiting parts. One end of the arm is fixed to the main body, and a through hole is formed between two adjacent arms. After one end of the limiting part is fixed to the main body, a guide groove is formed between the two adjacent limiting parts and the main body. The other end of the limiting part is provided with a matching part. The other end of the parking pawl matches the matching part. After one end of the push rod assembly passes through the through hole and enters the guide groove, one end of the push rod assembly matches the other end of the parking pawl.

[0012] One end of the compression spring assembly cooperates with the parking pawl, and the other end of the compression spring assembly cooperates with the baffle.

[0013] In the present invention, a mating portion is designed on the parking guide plate to contact the parking pawl, and the guide groove that cooperates with the push rod assembly is located below the mating portion. This can prevent the impact force of the parking pawl from directly acting on the push rod assembly, but instead transfers the impact force to the box body, thereby improving reliability. At the same time, under the joint action of the parking pawl and the parking guide plate, the compression spring assembly always applies an elastic force to the parking pawl, ensuring that the vibration resistance of the parking pawl is improved and preventing the pawl from falling due to failure of the parking pawl torsion spring. The connecting rod mechanism assembly can achieve multi-angle matching through angle and position adjustment. When its rotational movement drives the rocker arm assembly to rotate the designed angle, the split locking steel ball assembly locks it, so that the P gear or non-P gear is in a maintained state, to avoid failure in the P gear or non-P gear without operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of an existing parking actuator;

[0015] Figure 2 Schematic diagram of the parking actuator of the present invention;

[0016] Figure 3 Schematic diagram of the compression spring assembly structure;

[0017] Figure 4 This is a schematic diagram of a parking guide plate;

[0018] Figure 5 This is a schematic diagram of the split locking steel ball assembly structure;

[0019] Figure 6 Schematic diagram of the rocker arm assembly structure;

[0020] Figure 7 Schematic diagram of the connecting rod structure assembly.

[0021] Symbols in the accompanying drawings:

[0022] Parking ratchet 1, parking pawl 2, parking pawl pin 3, pawl return torsion spring 4, compression spring assembly 5, latch 51, compression spring 52, wear-resistant gasket 53, radial extension 54, parking guide plate 6, main body 60, arm 61, limiting portion 62, through hole 63, guide groove 64, matching portion 65, baffle 66, mounting slot 67, push rod assembly 7, split steel ball assembly 8, steel ball 81, compression spring 82, retaining ring 83, bolt 84; rocker arm assembly 9, mounting shaft 91, shift rocker arm 92, P gear matching portion 93a, non-P gear matching portion 93b, protrusion 94, rocker arm connecting hole 95; connecting rod mechanism assembly 10, shift shaft 101, shift arm 102, connecting rod arm 103, connecting pin 104a, pin 104b. DETAILED DESCRIPTION

[0023] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the scope of protection of the present invention.

[0024] In order to make the purpose, technical solutions and advantages of the present invention clearer, the technical solutions in the embodiments of the present invention are described in more detail in conjunction with the drawings in the embodiments of the present invention. The described embodiments are part of the embodiments of the present invention, not all of the embodiments. The embodiments described with reference to the drawings are exemplary and are intended to be used to explain the present invention, and should not be simply understood as limiting the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative work are within the scope of protection of the present invention.

[0025] like Figures 2 to 7 As shown, the automatic transmission parking actuator of the present invention includes a parking ratchet 1, a parking pawl 2, a parking pawl pin 3, a pawl return torsion spring 4, a push rod assembly 7, a power transmission mechanism, a parking guide plate 6, and a compression spring assembly 5. The following describes each component and the relationship between them in detail:

[0026] The teeth on the parking ratchet 1 are preferably rectangular in shape. The parking ratchet 1 is mounted to the transmission intermediate shaft via a spline to achieve torque bearing. The parking ratchet 1 mates with one end of the parking pawl 2. This engagement ensures that the parking position is engaged when the parking pawl 2 engages with the parking ratchet 1, and is released when the parking pawl 2 disengages from the parking ratchet 1.

[0027] The parking pawl pin 3 passes through the parking pawl 2. In this embodiment, preferably, the parking pawl 2 and the parking pawl pin 3 are matched with a hole-shaft clearance. Both ends of the parking pawl pin 3 are supported on the transmission case, and the parking pawl pin 3 and the transmission case also are matched with a hole-shaft clearance.

[0028] The pawl return torsion spring 4 is mounted on the parking pawl pin 3, with one end of the pawl return torsion spring 4 connected to the parking pawl 2. One end of the pawl return torsion spring 4 is inserted into the mating hole of the parking pawl 2, while the other end of the pawl return torsion spring 4 abuts against the limiting surface of the transmission case. This torque forces the end of the parking pawl 2 away from the top of the teeth of the parking ratchet wheel 1, ensuring that the parking pawl 2 does not fall when the gear is not in P.

[0029] One end of the push rod assembly 7 cooperates with the other end of the parking pawl 2, and the other end of the push rod assembly 7 is connected with the power transmission mechanism. The push rod assembly 7 consists of a push rod and a spring sleeved on the push rod.

[0030] The parking guide plate 6 includes a main body 60, at least two arms 61 and at least two limiting parts 62. One end of the arm 61 is fixed to the main body 60, and a through hole 63 is formed between two adjacent arms 61. After one end of the limiting part 62 is fixed to the main body 60, a guide groove 64 is formed between the two adjacent limiting parts 62 and the main body 60. The other end of the limiting part 62 is provided with a matching part 65, and the other end of the parking pawl 2 is matched with the matching part 65. After one end of the push rod assembly 7 passes through the through hole 63 and enters the guide groove 64, one end of the push rod assembly 7 is matched with the other end of the parking pawl 2.

[0031] The bottom surface of the guide groove 64 consists of a first bottom surface, a transition surface, and a second bottom surface. The height position of the first bottom surface is lower than the height position of the second bottom surface. One end of the transition surface is connected to the first bottom surface, and the other end of the transition surface is connected to the second bottom surface. The transition surface is an inclined surface or an arc surface.

[0032] Since one end of the push rod assembly 7 is located in the guide groove 64, and the guide groove 64 is located below the matching portion 65 (as seen in the figure), when the parking pawl 2 is retracted from the P gear to the non-P gear, it preferentially contacts the matching portion 65 on the parking guide plate 6 to prevent the impact force from directly acting on the push rod assembly 7. A mounting slot 67 for the compression spring assembly 5 is designed above the parking pawl 2, and avoids the maximum movement envelope of the parking pawl 2; when in the P gear state, the push rod assembly 7 is self-locked under the action of the split steel ball assembly 8 in the power transmission mechanism to ensure the parking function; in addition, two bolt holes connected to the transmission case are designed on the main body 60, and the parking guide plate 6 is fixed by bolts to prevent movement.

[0033] One end of the compression spring assembly 5 engages with the parking pawl 2, and the other end engages with the baffle 66. The compression spring assembly 5 includes a latch 51 and a compression spring 52. The other end of the parking pawl 2 has a mounting hole, which the latch 51 engages with. The compression spring 52 fits over the latch 51, and one end of the compression spring 52 engages with the parking pawl 2. The other end of the arm 61 has a baffle 66, which the other end of the compression spring 52 engages with. The compression spring assembly 5 also includes a wear-resistant washer 53, which fits over the latch 51 and is located between the other end of the compression spring 52 and the baffle 66. The other end of the latch 51 passes through the mounting slot 67. The other end of the latch 51 is provided with a radial extension portion 54. On the one hand, the grinding pad 53 is kept in cooperation with the baffle 66 through the action of the compression spring 52. On the other hand, the radial extension portion 54 cooperates with the baffle 66. When the parking pawl 2 rotates, the compression spring 52 is compressed or bounced open, and at the same time, the latch 51 can be moved.

[0034] The compression spring assembly 5 is designed as a redundant mechanism, and its pin 51 cooperates with the assembly hole on the parking pawl 2. One end of the compression spring 52 is close to the parking pawl 2, and the other end is close to the wear-resistant gasket 53. The wear-resistant gasket 53 is close to the baffle 66, thereby ensuring that the two ends are compressed to generate spring force, preventing the parking pawl 2 from rotating and colliding with the parking ratchet 1 when the pawl return torsion spring 4 fails, posing a safety hazard.

[0035] The power transmission mechanism includes a rocker arm assembly 9, a split steel ball assembly 8, and a connecting rod assembly 10. The power transmission mechanism is described in detail below:

[0036] The rocker arm assembly 9 is connected to the other end of the push rod assembly 7, and a P gear matching part 93a and a non-P gear matching part 93b are provided on the rocker arm assembly 9; the split steel ball assembly 8 provides locking force to the rocker arm assembly 9, and the split steel ball assembly 8 cooperates with the P gear matching part 93a or the non-P gear matching part 93b; the connecting rod mechanism assembly 10 is connected to the rocker arm assembly 9.

[0037] The split steel ball assembly 8 includes a steel ball 81, a compression spring 82, a retaining ring 83, and a bolt 84. The steel ball 81 cooperates with the rocker arm assembly 9. The steel ball 81 cooperates with one end of the compression spring 82, and the bolt 84 passes through the retaining ring 83 and cooperates with the other end of the compression spring 82.

[0038] Under the action of compression spring 82, steel ball 81 maintains engagement with P-range mating portion 93a or non-P-range mating portion 93b. The split steel ball assembly 8 provides a locking force to the rocker arm assembly 9 via compression spring 82, and is tightened to the transmission case via bolt 84 to prevent the mechanism from dislodging. A retaining ring 83, combined with compression spring 82 and bolt 84, seals the gap between bolt 84 and the transmission case, preventing leakage of fluids (e.g., lubricating oil) within the transmission.

[0039] The rocker arm assembly 9 includes a mounting shaft 91 and a shift rocker arm 92. The mounting shaft 91 is fixed to the shift rocker arm 92. The shift rocker arm 92 is provided with a protrusion 94. The protrusion 94 is provided with a mounting hole for assembly with the push rod assembly 7. The P gear matching portion 93a and the non-P gear matching portion 93b are arranged on the shift rocker arm 92.

[0040] The P gear matching part 93a and the non-P gear matching part 93b provided on the shift rocker arm 92 are both holes. After the P gear matching part 93a or the non-P gear matching part 93b is matched with the split steel ball assembly 8, the shift rocker arm 92 is in a locked state through the elastic force provided by the split steel ball assembly 8. When the connecting rod mechanism assembly 10 does not provide a force to the rocker arm assembly 9, the locking force provided by the split steel ball assembly 8 can prevent the rocker arm assembly 9 from rotating.

[0041] The mounting hole on the raised portion 94 is clearance-matched with the push rod assembly 7, and the shape of the mounting hole is designed to match the push rod assembly. The shift rocker arm 92 also has a rocker arm connection hole 95, which is riveted to the connecting rod assembly 10.

[0042] The connecting rod mechanism assembly 10 includes a shift shaft 101, a shift arm 102, a connecting rod arm 103, and a connecting pin 104a. The shift shaft 101 is fixed to the shift arm 102, the shift arm 102 is connected to the connecting rod arm 103 through the connecting pin 104a, and the other end of the shift arm 102 is connected to the rocker arm assembly 9.

[0043] The shift arm 102 is riveted to one end of the connecting arm 103 through a connecting pin 104a, and the other end of the connecting arm 103 is riveted to the shift rocker arm 92 in the rocker arm assembly 9 through a pin 104b. The entire force arm relationship is designed to be 1:1. When the shift shaft 101 welded to the shift arm 102 rotates a certain angle under the action of the driving motor, the connecting rod mechanism assembly 10 will drive the rocker arm assembly 9 to rotate the same angle.

[0044] When the parking actuator of the present invention shifts to P gear, the driving source drives the shift shaft 101 of the connecting rod assembly mechanism to rotate, the connecting rod mechanism assembly 10 drives the rocker arm assembly 9 to rotate, and the rocker arm assembly 9 drives the push rod assembly 7 to move axially in the guide groove 64 of the parking guide plate 6, and drives the parking pawl 2 to rotate around the parking pawl pin 3 by overcoming the tension of the compression spring assembly 5 and the torsion of the parking pawl torsion spring 4. When the tooth top of the parking pawl 2 is just opposite to the tooth top of the parking gear 1, a false P gear state is formed at this time; in this state, the spring on the push rod in the push rod assembly 7 is compressed to the maximum to store energy. When the parking ratchet 1 rotates an angle, the spring on the push rod in the push rod assembly 7 releases energy to push the parking pawl 2 to continue rotating, so that the parking pawl 2 enters the tooth groove of the parking gear 1. At this time, the split steel ball assembly 8 cooperates with and maintains the P gear matching part 93a, locks the state of the P gear, completes the whole process of the P gear, and realizes parking.

[0045] When disengaging from the P gear, the drive source drives the shift shaft 101 in the connecting rod assembly 10 to rotate in the opposite direction, which also drives the rocker arm assembly 9 to rotate in the opposite direction. The rocker arm assembly 9 then pulls the push rod assembly 7 in the opposite direction. When the parking pawl 2 rebounds, it strikes the mating portion 65 in the parking guide plate 6. The elastic force of the compression spring assembly 5 and the torsion of the parking pawl torsion spring 4 maintain a safe clearance between the parking pawl 2 and the parking ratchet 1. At this time, the split steel ball assembly 8 engages and maintains the non-P gear mating portion 93b, locking the non-P gear state and completing the P gear disengagement action.

Claims

1. An automatic transmission parking actuator comprises a parking ratchet (1), a parking pawl (2), a parking pawl pin (3), a pawl return torsion spring (4), a push rod assembly (7), and a power transmission mechanism, wherein the parking ratchet (1) cooperates with one end of the parking pawl (2), the parking pawl pin (3) passes through the parking pawl (2), the pawl return torsion spring (4) is sleeved on the parking pawl pin (3), one end of the pawl return torsion spring (4) is connected to the parking pawl (2), one end of the push rod assembly (7) cooperates with the other end of the parking pawl (2), and the other end of the push rod assembly (7) is connected to the power transmission mechanism, characterized in that: Also includes: A parking guide plate (6), the parking guide plate (6) includes a main body (60), at least two arms (61) and at least two limiting portions (62), one end of the arm (61) is fixed to the main body (60), a through hole (63) is formed between two adjacent arms (61), and after one end of the limiting portion (62) is fixed to the main body (60), a guide groove (64) is formed between the two adjacent limiting portions (62) and the main body (60), and the other end of the limiting portion (62) is provided with a matching portion (65), and the other end of the parking pawl (2) matches the matching portion (65), and after one end of the push rod assembly (7) passes through the through hole (63) and enters the guide groove (64), one end of the push rod assembly (7) matches the other end of the parking pawl (2); A compression spring assembly (5) having one end engaged with the parking pawl (2), and the other end of the compression spring assembly (5) engaged with the baffle (66); The compression spring assembly (5) includes: A latch (51), the other end of the parking pawl (2) is provided with an assembly hole, and the latch (51) cooperates with the assembly hole; A compression spring (52), the compression spring (52) is sleeved on the latch (51), one end of the compression spring (52) cooperates with the parking pawl (2), the other end of the arm (61) is provided with a baffle (66), and the other end of the compression spring (52) cooperates with the baffle (66); A mounting slot (67) for the compression spring assembly (5) is designed above the parking pawl (2); the other end of the latch (51) passes through the mounting slot (67), and the other end of the latch (51) is provided with a radial extension portion (54), which cooperates with the baffle (66). When the parking pawl (2) rotates, the compression spring (52) is compressed or springs open, causing the latch (51) to move.

2. The automatic transmission parking actuator according to claim 1, characterized in that: The bottom surface of the guide groove (64) consists of a first bottom surface, a transition surface, and a second bottom surface. The height of the first bottom surface is lower than the height of the second bottom surface. One end of the transition surface is connected to the first bottom surface, and the other end of the transition surface is connected to the second bottom surface.

3. The automatic transmission parking actuator according to claim 2, characterized in that: The compression spring assembly (5) further includes a wear-resistant gasket (53), which is sleeved on the latch (51). The wear-resistant gasket (53) is located between the other end of the compression spring (52) and the baffle (66).

4. The automatic transmission parking actuator according to claim 1, characterized in that: The power transmission mechanism includes: A rocker arm assembly (9), the rocker arm assembly (9) is connected to the other end of the push rod assembly (7), and the rocker arm assembly (9) is provided with a P gear matching portion (93a) and a non-P gear matching portion (93b); a split steel ball assembly (8) for providing a locking force to the rocker arm assembly (9), the split steel ball assembly (8) being engaged with the P gear engaging portion (93a) or the non-P gear engaging portion (93b); A connecting rod assembly (10) is connected to the rocker arm assembly (9).

5. The automatic transmission parking actuator according to claim 4, characterized in that: The split steel ball assembly (8) includes a steel ball (81), a compression spring (82), a retaining ring (83), and a bolt (84). The steel ball (81) cooperates with the rocker arm assembly (9). The steel ball (81) cooperates with one end of the compression spring (82), and the bolt (84) passes through the retaining ring (83) and cooperates with the other end of the compression spring (82).

6. The automatic transmission parking actuator according to claim 4, characterized in that: The rocker arm assembly (9) comprises a mounting shaft (91) and a shift rocker arm (92). The mounting shaft (91) is fixed to the shift rocker arm (92). The shift rocker arm (92) is provided with a protrusion (94). The protrusion (94) is provided with a mounting hole for assembling with the push rod assembly (7). The P gear matching portion (93a) and the non-P gear matching portion (93b) are provided on the shift rocker arm (92).

7. The automatic transmission parking actuator according to claim 4, characterized in that: The connecting rod mechanism assembly (10) comprises a shift shaft (101), a shift arm (102), a connecting rod arm (103), and a connecting pin (104a). The shift shaft (101) is fixed to the shift arm (102). The shift arm (102) is connected to the connecting rod arm (103) via the connecting pin (104a). The other end of the shift arm (102) is connected to the rocker arm assembly (9).

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