Armrest locking mechanism and seat

Abstract

The invention discloses an armrest locking mechanism and a seat, the armrest locking mechanism comprises an armrest shaft, the armrest shaft is sleeved with an unlocking cam and a locking cam, and when the armrest shaft rotates into an armrest locking interval, the unlocking cam and the locking cam are locked. The rotation angle of the armrest shaft relative to the locking cam is larger than that of the armrest shaft relative to the unlocking cam, so that the armrest shaft drives the unlocking cam to rotate to unlock the position of the locking cam; the armrest locking range of the armrest locking mechanism is suitable for a seat in a zero-gravity posture, the armrest is prevented from interfering with a cushion when located at the lowest critical position, and when the seat is in a flat lying posture, the armrest of the seat is roughly located at the horizontal position.

Description

Technical Field

[0001] This invention relates to the field of seat components technology, specifically to an armrest locking mechanism and a seat. Background Technology

[0002] Armrests, as a functional accessory for seats, are typically located on the sides of the seat and feature a rotating adjustment function. They provide support for the hands and improve seating comfort. Within a certain range, the armrest can be adjusted upwards to provide downward support for the hands. After adjusting upwards to a specific position, it can be adjusted bidirectionally throughout its entire travel until it returns to the lowest position, triggering the engagement of internal components to achieve unidirectional adjustment again.

[0003] Because it is locked at the lowest position, the downward adjustment range of the armrest is limited. Increasing this range would cause the armrest to interfere with the seat cushion during the downward adjustment to the lowest position, preventing the internal locking mechanism from being triggered. With the promotion of zero-gravity or reclining posture seats, the most comfortable hand position in this posture is close to horizontal, requiring the armrest to have a wide range of adjustment capabilities. Conventional armrests will be tilted upwards in the zero-gravity posture.

[0004] Therefore, how to solve the above-mentioned technical problems is a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0005] The purpose of this application is to provide an armrest locking mechanism, which can prevent the seat armrest from interfering with the seat cushion at the lowest position, and the seat armrest is in a roughly horizontal position when the seat is in a reclining position.

[0006] This application provides a handrail shaft with an unlocking cam and a locking cam sleeved on it. When the handrail shaft rotates into the handrail locking range, the rotation angle of the handrail shaft relative to the locking cam is greater than the rotation angle of the handrail shaft relative to the unlocking cam, so that the handrail shaft first drives the unlocking cam to rotate to release the locking position of the locking cam.

[0007] When the armrest drives the armrest shaft to rotate to the specified angle, the slider and ratchet are in a non-engaged position (maintaining the unlocking start position). The locking cam is restricted from circumferential rotation and cannot return to the locked position. Therefore, the armrest can be adjusted clockwise or counterclockwise within a certain range. This allows for a larger adjustment angle of the armrest, avoiding interference with the seat cushion when the armrest is in the lowest critical position. Furthermore, when the seat is in a reclined position, the armrest is roughly in a horizontal position.

[0008] When the handrail shaft rotates into the handrail locking range, the handrail shaft can rotate in a preset direction (as shown in the figure, counterclockwise, corresponding to the handrail rotating downwards). The handrail shaft first drives the unlocking cam to rotate, and the unlocking cam drives the holding block to move radially outwards to release the locking cam. During the rotation of the unlocking cam, the handrail shaft rotates relative to the locking cam during its free stroke. After the locking cam is unlocked, the slider of the handrail locking mechanism moves to the position where it engages with the ratchet.

[0009] In this way, the locking cam returns to the locked state to achieve the function of one-way adjustment, so that it can be locked at any position in the locking range, increasing the locking range of the armrest and making it suitable for seats in zero-gravity posture.

[0010] In one example, the handrail shaft is further fitted with a sliding plate and a ratchet. The sliding plate is provided with a slider and a retaining block that can move reciprocally in the radial direction. The outer end of the slider can engage with the ratchet. A return spring is connected between the sliding plate and the locking cam. After the locking cam is unlocked, it returns to the locked position under the action of the return spring, so that the slider engages with the ratchet.

[0011] In one example, the slide plate is provided with a retaining block that can reciprocate radially. When the handrail rotates to a designated position, the retaining block engages with the locking cam to prevent the locking cam from returning to the locked position, and the slider and the ratchet are in a non-engaged state. When the handrail shaft reaches the handrail locking range, the handrail shaft first drives the unlocking cam to rotate. The unlocking cam drives the retaining block to move radially outward to release the locking cam. During the rotation of the unlocking cam, the handrail shaft rotates relative to the locking cam during its idle stroke.

[0012] In one example, the armrest shaft is provided with a first spline tooth, and the center hole of the locking cam has a second spline tooth. The first spline tooth and the second spline tooth are in clearance fit so that the armrest shaft can rotate relative to the locking cam during the unlocking process at the designated position.

[0013] In one example, the outer surface of the armrest shaft is provided with a non-circular toothed surface, the roots of a group of adjacent first spline teeth of the armrest shaft are connected by an arc, and the distance between them is greater than the distance between other adjacent first spline teeth. The center holes of the locking cam and the unlocking cam are non-circular holes to match the armrest shaft.

[0014] In one example, the outer peripheral wall of the locking cam includes a first protrusion, and the end of the slider opposite to the locking cam includes a first groove. The first protrusion is inserted into the interior of the first groove. When the locking cam rotates circumferentially, the locking cam drives the slider to move radially by abutting against the inner walls of the first protrusion and the first groove.

[0015] In one example, the outer peripheral wall of the locking cam further includes a second protrusion, and the end of the slider opposite to the locking cam further includes a second groove. The second protrusion is inserted into the interior of the second groove. When the locking cam rotates circumferentially, the locking cam abuts against the inner wall of the second groove through the second protrusion, and the abuts against the inner wall of the first groove through the first protrusion, together driving the slider to move radially.

[0016] In one example, a camshaft sleeve is also included, the camshaft sleeve comprising a sleeve section and an annular protrusion protruding from the outer periphery of the sleeve section, the sleeve section being fitted onto the armrest shaft, the annular protrusion being circumferentially limited to the locking cam, one end of the return spring being limited to the side of the slide plate facing the camshaft sleeve, and the other end being limited to the peripheral wall of the sleeve section.

[0017] In one example, when the handrail is not in the handrail locking range, the retaining block engages with the locking cam to prevent the locking cam from returning to the locking position, and the slider and the ratchet are in a non-engaged state.

[0018] In one example, the ratchet also includes a resilient retaining spring. One side of the ratchet has a countersunk hole, and the resilient retaining spring is installed in the countersunk hole. The armrest shaft has an annular groove, and the resilient retaining spring partially protrudes and engages with the annular groove to limit the axial position of the armrest shaft and the ratchet. Alternatively / and, it also includes a transition plate, wherein one of the transition plate and the ratchet is provided with a boss and the other is provided with a mounting hole, the boss being inserted into the mounting hole and the two being welded together.

[0019] In one example, a retaining spring is also included, the slide plate is provided with a mounting groove, the retaining spring is disposed inside the mounting groove, and the retaining spring applies a radial force to the retaining block toward the locking cam side so that the retaining block abuts against the locking cam.

[0020] In addition, this application also provides a seat, including the armrest locking mechanism described in any of the above claims, wherein the armrest shaft is connected to the armrest of the seat, and the ratchet is directly or indirectly connected to the backrest of the seat. Attached Figure Description

[0021] Figure 1This is a schematic diagram of the structure of a seat provided in one embodiment of this application; Figure 2 for Figure 1 The diagram shows the positions of the backrest, armrests, and armrest locking mechanism in the seat; it also shows several different rotational positions of the armrests. Figure 3 This is a schematic diagram of the handrail locking mechanism provided in one embodiment of this application; Figure 4 for Figure 3 An exploded view of the handrail locking mechanism shown. Figure 5 for Figure 1 The diagram shows the relative positions of the components of the handrail locking mechanism when the handrail is in position A. Figure 6 for Figure 1 The diagram shows the locking cam that holds the handrail in position E. Figure 7 for Figure 1 The diagram shows the relative positions of each component when the unlocking cam unlocks the retaining block and the locking cam when the handrail is in position E. Figure 8 for Figure 1 The diagram shows the locking cam returning to the locked position when the handrail is in position E. Figure 9 for Figure 1 The diagram shows the positions of the components in the handrail locking mechanism when the handrail is in position B. Figure 10 for Figure 1 The diagram shows the positions of the components in the handrail locking mechanism when the handrail is in position C. Figure 11 for Figure 1 The diagram shows the positions of the components in the handrail locking mechanism when the handrail is in position D. Figure 12 for Figure 3 An exploded view of the locking cam, camshaft sleeve, return spring, and handrail shaft in the handrail locking mechanism shown. Figure 13 for Figure 3 The diagram shows the assembly of the return spring, camshaft sleeve, and slide plate in the handrail locking mechanism. Figure 14 for Figure 3 A schematic diagram of some components in the handrail locking mechanism shown; Figure 15 for Figure 14 The image shows the front view of the assembled components. Figure 16This is a schematic diagram of the transition plate and ratchet in the handrail locking mechanism; Figure 17 for Figure 6 The diagram shows the difference in rotation angle between the locking cam and the armrest shaft.

[0022] in, Figures 1 to 17 The annotations in the accompanying drawings are explained as follows: 200 Handrail locking mechanism; 1 Transition plate; 11 Mounting hole; 2 Elastic snap ring; 3 Retaining spring; 4 Ratchet; 41 First half-punch boss; 5 Retaining block; 51 Recess; 6 Slide plate; 61 First slide groove; 62 Second slide groove; 63 Protrusion; 7 Unlocking cam; 8 Protective sleeve; 9 Return spring; 15 Locking cam; 151 Second spline tooth; 152 Second half-punch boss; 153 First protrusion; 154 Second protrusion; 155 Locking part; 16 Slider; 161 First groove; 162 Second groove; 17 Handrail shaft; 173 First spline tooth; 18 Cam shaft sleeve; 181 Hole; 101 Armrests; 102 Backrest; 103 Seat Cushion. Detailed Implementation

[0023] To enable those skilled in the art to better understand the technical solutions of the embodiments of this application, the embodiments of this application will be further described in detail below with reference to the accompanying drawings and specific examples.

[0024] Please refer to Figures 1 to 17 , Figure 1 This is a schematic diagram of the structure of a seat provided in one embodiment of this application; Figure 2 for Figure 1 The diagram shows the positions of the backrest, armrests, and armrest locking mechanism in the seat; it also shows several different rotational positions of the armrests. Figure 3 This is a schematic diagram of the handrail locking mechanism provided in one embodiment of this application; Figure 4 for Figure 3 An exploded view of the handrail locking mechanism shown. Figure 5 for Figure 1 The diagram shows the relative positions of the components of the handrail locking mechanism when the handrail is in position A. Figure 6 for Figure 1 The diagram shows the locking cam that holds the handrail in position E. Figure 7 for Figure 1 The diagram shows the relative positions of each component when the unlocking cam unlocks the retaining block and the locking cam when the handrail is in position E. Figure 8 for Figure 1 The diagram shows the locking cam returning to the locked position when the handrail is in position E. Figure 9 for Figure 1 The diagram shows the positions of the components in the handrail locking mechanism when the handrail is in position B. Figure 10 for Figure 1 The diagram shows the positions of the components in the handrail locking mechanism when the handrail is in position C. Figure 11 for Figure 1 The diagram shows the positions of the components in the handrail locking mechanism when the handrail is in position D. Figure 12 for Figure 3 An exploded view of the locking cam, camshaft sleeve, return spring, and handrail shaft in the handrail locking mechanism shown. Figure 13 for Figure 3 The diagram shows the assembly of the return spring, camshaft sleeve, and slide plate in the handrail locking mechanism. Figure 14 for Figure 3 A schematic diagram of some components in the handrail locking mechanism shown; Figure 15 for Figure 14 The image shows the front view of the assembled components. Figure 16 This is a schematic diagram of the transition plate and ratchet in the handrail locking mechanism; Figure 17 for Figure 6 The diagram shows the difference in rotation angle between the locking cam and the armrest shaft. Figure 1 The document provides five positions for the handrail rotation: A, B, C, D, and E. A represents the lowest position of the handrail within the locking range, B represents the highest position within the locking range, and E represents a specific position within the locking range. C and D represent positions outside the locking range.

[0025] This application provides a seat, including a backrest 102, a seat cushion 103, and armrests 101. This seat can be used in automobiles, i.e., as a car seat. Of course, it can also be applied to other fields, such as massage chairs. The backrest 102 provides support for the user's back, and the armrests provide support for the user's arms.

[0026] In this embodiment, the armrest is connected to the backrest 102 via an armrest locking mechanism 200. The armrest can rotate within the locking range via the armrest locking mechanism 200 and be constrained to several positions or any position within the locking range. When the armrest moves out of the locking range, it can rotate freely relative to the backrest 102 without being locked.

[0027] In this embodiment, the handrail locking mechanism 200 includes a handrail shaft 17, a slide plate 6, a ratchet 4, an unlocking cam 7, a locking cam 15, a return spring 9, and a protective sleeve 8. The protective sleeve 8 can limit the axial movement of the ratchet 4 relative to the slide plate 6, thereby maintaining the relative axial stability of the internal components (locking cam 15, retaining block 5, unlocking cam 7), and the protective sleeve 8 can limit the ratchet 4 to be approximately concentric with the slide plate 6 when rotating. The slide plate 6, ratchet 4, unlocking cam 7, and locking cam 15 are all provided with coaxial through holes, and the handrail shaft 17 passes through the through holes of the slide plate 6, ratchet 4, unlocking cam 7, and locking cam 15. That is, the slide plate 6, ratchet 4, unlocking cam 7, and locking cam 15 are sleeved on the handrail shaft 17. The locking cam 15 and the unlocking cam 7 can rotate circumferentially with the armrest shaft 17. The armrest shaft 17 and the locking cam 15 can be circumferentially limited by toothed engagement, and the armrest shaft 17 and the unlocking cam 7 can also be circumferentially limited by toothed engagement. Alternatively, the armrest shaft 17 and the locking cam 15 can also be engaged by grooves and protrusions on their sides to allow the locking cam 15 to rotate with the armrest shaft 17. Similarly, the armrest shaft 17 and the unlocking cam 7 can also be engaged by grooves and protrusions on their sides to allow the unlocking cam 7 to rotate with the armrest shaft 17.

[0028] In this embodiment, the ratchet 4 can be directly or indirectly fixed to the backrest 102. This application shows that the armrest locking mechanism 200 also includes a transition plate 1, and the ratchet 4 is fixed to the transition plate 1. The ratchet 4 can be fixedly connected to the transition plate 1 by welding, or it can be fixedly connected to the transition plate 1 by non-welding methods such as bolts or riveting. The transition plate 1 is fixed to the backrest 102. The transition plate 1 can be fixedly connected to the backrest 102 by welding, or it can be fixedly connected to the backrest 102 by non-welding methods such as bolts or riveting.

[0029] Welded connections take up less space, which is beneficial for miniaturizing the handrail locking mechanism 200. Of course, non-welded connections make it easier to disassemble the handrail locking mechanism 200, facilitate the replacement of some parts of the handrail locking mechanism 200, and reduce maintenance costs.

[0030] In one specific embodiment, the mounting surface of the ratchet 4 is provided with two first half-punch protrusions 41, and the transition plate 1 is provided with two mounting holes. The first half-punch protrusions 41 correspond one-to-one with the mounting holes, and the first half-punch protrusions 41 are inserted into the mounting holes and welded together. Of course, it is also possible to provide the first half-punch protrusions 41 on the transition plate 1 and the mounting holes on the ratchet 4. In this embodiment, the ratchet 4 and the transition plate 1 are reliably fixed by local welding connection, and the connection occupies little space.

[0031] In this embodiment of the application, the armrest shaft 17 can be connected to the armrest by welding or other means.

[0032] The slider 16 and the retaining block 5 are slidably disposed on the slide plate 6. Correspondingly, the slide plate 6 has a first slide groove 61 and a second slide groove 62, both of which extend radially. The slider 16 slides relative to the slide plate 6 along the first slide groove 61. The retaining block 5 slides relative to the slide plate 6 along the second slide groove 62. The number of sliders 16 can be at least one, with one slider 16 corresponding to one first slide groove 61. The figure shows an embodiment with two sliders 16, which are symmetrically distributed about the center of the slide plate 6. Of course, the number of sliders 16 can also be three or four or more. The end of the slider 16 away from the handrail shaft 17 is provided with teeth that mesh with the ratchet 4. The more sliders 16 there are, the greater the meshing force between the slider 16 and the ratchet 4, thus improving the reliability of the handrail in the locked state.

[0033] Similarly, the number of retaining blocks 5 can be one or more. In one embodiment, the side of the slide plate 6 is provided with multiple protrusions 63, and a first slide groove 61 or a second slide groove 62 is formed between adjacent protrusions 63. The figure shows an example where the side of the slide plate 6 is provided with four protrusions 63, and the number of first slide grooves 61 is two or one. The four protrusions 63 have the same structure, so the first slide groove 61 and the second slide groove 62 have essentially the same structure.

[0034] In this embodiment, a return spring 9 is also connected between the slide plate 6 and the locking cam 15. The main function of the return spring 9 is to provide the restoring force for the locking cam 15 to return to the locking position.

[0035] When the handrail locking mechanism 200 of this application is in use, taking the movement of the handrail in the locking range as an example, the handrail drives the handrail shaft 17 to rotate around the central axis of the handrail shaft 17. The handrail shaft 17 drives the locking cam 15 to rotate in the unlocking direction (clockwise). Its locking surface gradually moves away from the locking surface of the slider 16. The return spring 9 is also subjected to a counterclockwise force. One end of the return spring 9 is connected to the slide plate 6, so the slide plate 6 is also subjected to a counterclockwise force. Since the slider 16 resists the counterclockwise rotation of the slide plate 6, the counterclockwise rotational force on the slide plate 6 is ultimately applied to the slider 16. As the locking cam 15 rotates away from the slider 16, the slider 16 moves downward after being subjected to force, always in contact with the locking cam 15. The teeth of the slider 16 gradually disengage from the ratchet 4, thereby realizing the upward adjustment of the handrail.

[0036] When the handrail stops at any position in the locking range, the locking cam 15 can return to the initial locking position under the action of the return spring 9, and the slider 16 returns to the position of engaging with the ratchet 4. Furthermore, due to the obstruction of the bottom contour of the locking cam 15 and the slider 16, it cannot rotate counterclockwise, thus achieving the function of reverse locking.

[0037] Please refer to Figure 6When the armrest drives the armrest shaft 17 to rotate to a specified angle, the slider 16 and the ratchet 4 are in a non-engaged position. The retaining block 5 restricts the circumferential rotation of the locking cam 15, and the locking cam 15 cannot return to the locked position. Therefore, the armrest can be adjusted clockwise or counterclockwise within a certain range, so that the adjustment angle of the armrest is larger and interference with the seat cushion is avoided when the armrest is in the lowest critical position.

[0038] When the armrest shaft 17 rotates into the armrest locking range, as it rotates in a preset direction (counterclockwise as shown in the figure, corresponding to the armrest rotating downwards), the armrest shaft 17 first drives the unlocking cam 7 to rotate. The unlocking cam 7 drives the holding block 5 to move radially outwards to release the lock on the locking cam 15. During the rotation of the unlocking cam 7, the armrest shaft 17 rotates relative to the locking cam 15 during its free travel. After the locking cam is unlocked, it returns to the locked position under the action of the return spring 9, and the slider 16 of the armrest locking mechanism moves to the position where it engages with the ratchet 4. In this way, the locking cam 15 returns to the locked state, realizing the function of unidirectional adjustment, thereby enabling locking at any position within the locking range and increasing the armrest locking range, making it suitable for seats in a zero-gravity posture.

[0039] Please refer to the following: Figure 7 , Figure 8 as well as Figure 17 It is understood that the relative motion angle between the armrest shaft 17 and the unlocking cam 7 is less than the relative motion angle between the armrest shaft 17 and the locking cam 15 (assuming the relative motion angle between the armrest shaft 17 and the unlocking cam 7 is a (a=0 in the patent figure), and the relative motion angle between the armrest shaft 17 and the locking cam 15 is b, then a < b must be satisfied). During the reverse motion, the armrest shaft 17 will first drive the unlocking cam 7 to rotate clockwise. The irregular protrusion on the unlocking cam 7 contacts the boss on the retaining block 5 and pushes the retaining block 5 to move outward, releasing the interlocking state between the retaining block 5 and the locking cam 15. Once the retaining block 5 is released from the interlocking with the locking cam 15, the retaining block 5, the slider 16, and the slide plate 6 can move counterclockwise under the force of the return spring 9. The slider 16 can move outward along the locking surface of the slider 16 during the counterclockwise movement of the slide plate 6 until it engages with the ratchet 4.

[0040] This allows the handrail to continue rotating upwards, thus adjusting its angle.

[0041] The retaining block 5 may be provided with a recess 51, and the locking cam 15 may be provided with a locking part 155. The locking part 155 may be a protrusion, which is inserted into the recess 51 to restrict the rotation of the locking cam 15.

[0042] In one embodiment, the armrest shaft 17 is provided with a first spline tooth 173, and the center hole of the locking cam has a second spline tooth 151. The first spline tooth 173 and the second spline tooth 151 are in clearance fit so that the armrest shaft 17 can rotate relative to the locking cam during the unlocking process at a designated position. The spline-driven circumferential transmission structure between the two is relatively simple and has good adjustment continuity.

[0043] In one specific embodiment, the outer surface of the armrest shaft 17 is provided with a non-circular toothed surface. The roots of a group of adjacent first spline teeth 173 of the armrest shaft 17 are connected by an arc, and the distance between them is greater than the distance between other adjacent first spline teeth 173. The center holes of the locking cam and the unlocking cam 7 are non-circular holes to match the armrest shaft 17. In this way, the armrest shaft 17 can be installed at a specific angle, ensuring the uniqueness of the assembly angle and preventing incorrect installation.

[0044] There are multiple ways to set the locking surfaces between the slider 16 and the locking cam 15. This application provides a specific setting method.

[0045] Please refer to Figures 5 to 11 14. In one embodiment, the outer peripheral wall of the locking cam 15 includes a first protrusion 153, and the end of the slider 16 opposite to the locking cam 15 includes a first groove 161. The first protrusion 153 is inserted into the interior of the first groove 161. When the locking cam 15 rotates circumferentially, the locking cam 15 drives the slider 16 to move radially by abutting against each other through the inner walls of the first protrusion 153 and the first groove 161.

[0046] Furthermore, the outer peripheral wall of the locking cam 15 also includes a second protrusion 154, and the end of the slider 16 opposite to the locking cam 15 also includes a second groove 162. The second protrusion 154 is inserted into the interior of the second groove 162. When the locking cam 15 rotates circumferentially, the locking cam 15 abuts against the inner wall of the second groove 162 through the second protrusion 154, and together with the inner wall of the first protrusion 153 and the first groove 161, drives the slider 16 to move radially. In this embodiment, the contact surface between the locking cam 15 and the slider 16 is relatively large, the driving stability is relatively high, and excessive local force can be avoided to prevent damage to the locking cam 15 or the slider 16.

[0047] In this embodiment, the handrail locking mechanism 200 may further include a camshaft sleeve 18. The camshaft sleeve 18 includes a sleeve section and an annular protrusion protruding from the outer periphery of the sleeve section. The sleeve section is fitted onto the handrail shaft 17. The annular protrusion and the locking cam 15 are circumferentially limited and connected. One end of the return spring 9 is limited and connected to the side of the slide plate 6 facing the camshaft sleeve 18, and the other end is limited and connected to the peripheral wall of the sleeve section. In a specific embodiment, one end of the return spring 9 is hooked into the groove on the side of the slide plate 6, and the other end is hooked into the groove on the peripheral wall of the sleeve section, reducing the space required for the installation of the return spring 9. The camshaft sleeve 18 and the locking cam 15 may also have a concave-convex fit and be welded together at the concave-convex fit position. For example, the side of the locking cam 15 is provided with a second half-punch protrusion 152, and the annular protrusion is provided with a hole 181 that mates with the second half-punch protrusion 152. The second half-punch protrusion 152 is inserted into the hole 181 and welded together.

[0048] In this embodiment, the camshaft sleeve 18 provides a base for the installation of the return spring 9, which can optimize the force on the locking cam 15.

[0049] In this embodiment, the handrail locking mechanism 200 may further include an elastic retaining spring 2. A countersunk hole is provided on one side of the ratchet 4, and the elastic retaining spring 2 is installed in the countersunk hole. An annular groove is provided on the handrail shaft 17, and the elastic retaining spring 2 protrudes partially and engages with the annular groove to limit the axial position of the handrail shaft 17 and the ratchet 4.

[0050] In this embodiment of the application, the handrail locking mechanism 200 may further include a retaining spring 3, the slide plate 6 is provided with a mounting groove, the retaining spring 3 is disposed inside the mounting groove, and the retaining spring 3 applies a radial force to the retaining block 5 toward the locking cam 15 so that the retaining block 5 abuts against the locking cam 15.

[0051] After the armrest in this application moves out of the locking zone, that is, when the armrest is not in the locking zone, the retaining block 5 can engage with the locking cam 15 to lock it, so as to prevent the locking cam 15 from returning to the locking position. The slider 16 and the ratchet 4 are in a non-engaged state, so the position of the armrest can be adjusted at will, and can be adjusted to the backrest 102 position.

[0052] As shown in the figure, after the handrail rotates away from the highest boundary position of the locking zone, the holding block 5 will engage with the locking cam 15 to lock it, preventing the locking cam 15 from returning to the locked position. At this time, the handrail can rotate freely, further improving the flexibility of the handrail.

[0053] The seat provided in this application includes the aforementioned armrest locking mechanism 200, and therefore also has the aforementioned technical effects of the armrest locking mechanism 200.

[0054] In the description of embodiments of this application, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus.

[0055] In the description of embodiments of this application, the terms "perpendicular," "parallel," and "equal" include the described situation and situations that are similar to the described situation, where the range of similar situations is within an acceptable deviation range, wherein the acceptable deviation range is, for example, within 5°, 8°, or 10°. "Perpendicular" includes absolute perpendicularity and approximately perpendicularity, wherein the acceptable deviation range for approximately perpendicularity can also be, for example, within 5°, 8°, or 10°. "Equal" includes absolute equality and approximately equality, wherein the acceptable deviation range for approximately equality can be, for example, the difference between two equal persons being less than or equal to 5%, 8%, or 10% of either one.

[0056] The above are merely preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A handrail locking mechanism, characterized in that, Includes an armrest shaft (17), on which an unlocking cam (7) and a locking cam (15) are fitted. When the armrest shaft rotates into the armrest locking range, the rotation angle of the armrest shaft (17) relative to the locking cam (15) is greater than the rotation angle of the armrest shaft relative to the unlocking cam, so that the armrest shaft (17) first drives the unlocking cam (7) to rotate to release the locking cam (15) from the position.

2. The handrail locking mechanism according to claim 1, characterized in that, The handrail shaft is also fitted with a sliding plate (6) and a ratchet (4). The sliding plate (6) is provided with a slider (16) that can move back and forth in the radial direction and a retaining block (5). The outer end of the slider (16) can engage with the ratchet (4). A return spring (9) is connected between the sliding plate (6) and the locking cam (15). After the locking cam is unlocked, it returns to the locked position under the action of the return spring (9) so that the slider (16) engages with the ratchet (4).

3. The handrail locking mechanism according to claim 2, characterized in that, The slide plate (6) is provided with a retaining block (5) that can reciprocate radially. When the handrail rotates to the designated position, the retaining block (5) locks with the locking cam (15) to restrict the locking cam (15) from returning to the locked position. The slider (16) and the ratchet (4) are in a non-engaged state. When the handrail rotates to the handrail locking range, the handrail shaft first drives the unlocking cam (7) to rotate. The unlocking cam (7) drives the retaining block (5) to move radially outward to release the lock on the locking cam (15). During the rotation of the unlocking cam (7), the handrail shaft rotates relative to the locking cam (15) during its free stroke.

4. The handrail locking mechanism according to claim 3, characterized in that, The armrest shaft is provided with a first spline tooth, and the center hole of the locking cam has a second spline tooth. The first spline tooth and the second spline tooth are in clearance fit so that the armrest shaft can rotate relative to the locking cam during the unlocking process of the locking cam at the designated position.

5. The handrail locking mechanism according to claim 4, characterized in that, The outer surface of the armrest shaft is provided with a non-shaped tooth surface. The tooth roots of a group of adjacent first spline teeth of the armrest shaft are connected by an arc, and the distance between them is greater than the distance between other adjacent first spline teeth. The center holes of the locking cam and the unlocking cam (7) are non-shaped holes to match the armrest shaft.

6. The handrail locking mechanism according to any one of claims 1 to 5, characterized in that, The outer peripheral wall of the locking cam (15) includes a first protrusion, and the end of the slider (16) opposite to the locking cam (15) includes a first groove. The first protrusion is inserted into the interior of the first groove. When the locking cam (15) rotates circumferentially, the locking cam (15) drives the slider (16) to move radially by abutting against the inner wall of the first protrusion and the first groove.

7. The handrail locking mechanism according to claim 6, characterized in that, The outer peripheral wall of the locking cam (15) also includes a second protrusion, and the end of the slider (16) opposite to the locking cam (15) also includes a second groove. The second protrusion is inserted into the interior of the second groove. When the locking cam (15) rotates circumferentially, the locking cam (15) abuts against the inner wall of the second groove through the second protrusion, and the first protrusion and the inner wall of the first groove abut against each other together drive the slider (16) to move radially.

8. The handrail locking mechanism according to any one of claims 3 to 5, characterized in that, It also includes a camshaft sleeve (18), which includes a sleeve section and an annular protrusion protruding from the outer periphery of the sleeve section. The sleeve section is fitted onto the armrest shaft. The annular protrusion is circumferentially limited to the locking cam (15). One end of the return spring (9) is limited to the side of the slide plate (6) facing the camshaft sleeve (18), and the other end is limited to the peripheral wall of the sleeve section. Alternatively / when the handrail is not in the handrail locking range, the holding block (5) engages with the locking cam (15) to restrict the locking cam (15) from returning to the locking position, and the slider (16) is in a non-engaged state with the ratchet (4).

9. The handrail locking mechanism according to any one of claims 3 to 5, characterized in that, It also includes an elastic retaining ring (2), one side of the ratchet (4) is provided with a countersunk hole, the elastic retaining ring (2) is installed in the countersunk hole, the armrest shaft is provided with an annular groove, the elastic retaining ring (2) is partially protruding and engaged in the annular groove to limit the axial position of the armrest shaft and the ratchet (4); Or / and, also includes a transition plate (1), one of the transition plate (1) and the ratchet (4) is provided with a boss, and the other is provided with a mounting hole, the boss is inserted into the mounting hole and the two are welded together; Alternatively and / or, it also includes a retaining spring (3), the slide plate (6) is provided with a mounting groove, the retaining spring (3) is disposed inside the mounting groove, the retaining spring (3) applies a radial force to the retaining block (5) toward the locking cam (15) so that the retaining block (5) abuts against the locking cam (15).

10. A type of seat, characterized in that, Includes the armrest locking mechanism according to any one of claims 1 to 9, wherein the armrest shaft is connected to the armrest of the seat, and the ratchet (4) is directly or indirectly connected to the backrest (102) of the seat.

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