Front-back swing adjusting mechanism and seat
By using a front-to-back swing adjustment mechanism, and through the cooperation of guide grooves and locking pins, the problem of cumbersome operation of traditional seat lumbar and headrest pillows is solved, achieving stable support and easy adjustment.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- HANGZHOU HEIBAIDIAO TECH CO LTD
- Filing Date
- 2025-06-26
- Publication Date
- 2026-05-05
AI Technical Summary
Traditional chairs have cumbersome lumbar and headrests that are easy to detach and do not provide stable support.
The device employs a front-to-back swing adjustment mechanism, including a fixed seat, a movable seat, and a locking element. It utilizes the cooperation of guide grooves and locking pins to provide stable support through elastic elements, and the position of the support unit can be adjusted by one hand.
It provides stable support, preventing the support unit from shifting abnormally backward. It is simple and convenient to operate, and the position can be adjusted with one hand.
Smart Images
Figure CN224193181U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of seat technology, specifically to a fore-and-aft swing adjustment mechanism and a seat. Background Technology
[0002] Traditional chairs provide support through seat cushions and backrests, with the backrest fixed relative to the seat cushion. The lack of lumbar or head support structures on the backrest leaves the user's head, neck, and lower back unsupported, leading to fatigue. To overcome these shortcomings, some office and study chairs are equipped with lumbar and headrests. To accommodate different body shapes and postures, these support units are adjustable, allowing them to swing back and forth relative to the backrest support. When the support unit is moved to the desired position, a locking mechanism secures it. Current locking mechanisms typically use a through-bolt to lock two rotating parts. Adjusting the support unit requires pulling the bolt with one hand and swinging the unit with the other, a cumbersome process. The bolt is prone to disengagement, making it difficult for the support unit to provide stable support; in other words, the support unit may shift abnormally backward. Utility Model Content
[0003] The purpose of this invention is to provide a front-to-back swing adjustment mechanism and a seat that is easy to operate and can provide stable support.
[0004] To achieve the above objectives, the present invention adopts the following technical solution:
[0005] The front and rear swing adjustment mechanism includes a fixed base, a movable base, and a locking component;
[0006] The movable seat includes a rotating end and a free end opposite to the rotating end. The rotating end is pivotally connected to the fixed seat so that the free end can swing back and forth relative to the fixed seat.
[0007] The free end of the movable seat is provided with a guide groove extending in the front-to-back direction. The guide groove includes a first side wall and a second side wall opposite to the first side wall. The first side wall is provided with a plurality of locking grooves recessed away from the second side wall. The plurality of locking grooves are arranged sequentially from front to back. The movable seat is provided with a guiding part, a first actuating part connected to the rear end of the guiding part, and a second actuating part located at the end of the plurality of locking grooves away from the first actuating part.
[0008] The fixed base is provided with a locking part, the locking member is installed on the fixed base and is provided with a locking pin extending into the guide groove. The locking member is installed on the fixed base and is configured to be able to move back and forth between a first position and a second position, and to swing left and right between a third position and a fourth position. When the locking member is in the first position, it has the freedom to swing between the third position and the fourth position. When the locking member is in the second position, the locking member cooperates with the locking part on the fixed base to keep the locking member in the fourth position.
[0009] An elastic element is provided between the fixed base and the locking element. The elastic element is used to apply elastic stress to the locking element so that the locking element always maintains the tendency to swing toward the third position.
[0010] When the locking member is in the third position, the locking pin is engaged in one of the slots. When the locking member is in the fourth position, the locking pin disengages from the slot and is placed in the guide groove. The guide part is used to guide the locking pin so that the locking member is in the fourth position. The first actuating part is used to push the locking pin forward when moving forward relative to the locking pin so that the locking member moves from the first position to the second position. The second actuating part is used to push the locking pin backward when moving backward relative to the locking pin so that the locking member disengages from the locking part.
[0011] Preferably, the locking groove includes a baffle extending from the first sidewall of the guide groove toward the direction away from the second sidewall, and an inclined guide wall extending from the end of the baffle away from the second sidewall to the first sidewall. When the locking member is in the third position, the locking pin abuts against the baffle. The inclined guide wall is used to push the locking pin toward the fourth position when the free end of the movable seat moves forward relative to the fixed seat.
[0012] Preferably, the guide groove includes a rear end wall connected between the rear ends of the first side wall and the second side wall, and a front end wall connected between the front ends of the first side wall and the second side wall. The rear end wall forms a first actuating part, and the front end wall forms a second actuating part. The portion of the guide groove located between the last side of the locking groove and the rear end wall forms a guiding part. The baffle of the frontmost locking groove is connected to the front end wall and is flush with each other.
[0013] Preferably, the cross-section of the locking post is elongated.
[0014] Preferably, the fixed seat includes two side walls and an outer end wall located between the ends of the two side walls away from the free end of the movable seat. The two side walls and the outer end wall together form a receiving groove with a front opening for accommodating the movable seat. The rotating end of the movable seat is pivotally connected to the ends of the two side walls away from the outer end wall via a pivot shaft. A guide groove is formed on the end face of the free end of the movable seat.
[0015] Preferably, a groove is provided on the outer end wall, which is recessed from its outer surface to its inner surface. A through groove is provided on the bottom surface of the groove, extending to the inner surface of the outer end wall. The locking member is placed in the groove, and the locking pin is inserted into the guide groove after passing through the through groove.
[0016] Preferably, the rear end face of the groove is provided with a first recessed notch, the locking part is a second recessed notch located on the front end face of the groove, the rear end of the locking member forms a rotating part and the front end forms a locking end, the rotating part is embedded in the first notch so that the locking member can swing left and right between the third position and the fourth position, when the locking member is in the second position, the rotating part is placed in the first notch and the locking end is placed in the second notch.
[0017] Preferably, the outer end wall of the fixed seat and the end face of the free end of the movable seat are both arc-shaped.
[0018] Preferably, a cover plate is detachably fixed to the outer end wall, the cover plate being placed outside the groove and sealing the outside of the locking member.
[0019] The seat includes the aforementioned fore-and-aft swing adjustment mechanism.
[0020] Compared with the prior art, the beneficial effects of this utility model are as follows:
[0021] The forward and backward swing adjustment mechanism of this utility model can provide stable support for the user's body, prevent the seat support unit from moving backward abnormally, and when it is necessary to adjust the forward and backward position of the support unit, the user can adjust the support unit by pushing it forward or backward with one hand. The operation process is simple and convenient. Attached Figure Description
[0022] Figure 1 This is a schematic diagram of the structure of this utility model;
[0023] Figure 2 for Figure 1 Schematic diagram of the central locking component;
[0024] Figure 3 for Figure 1 Schematic diagram of the structure of the movable seat;
[0025] Figure 4 This is a schematic diagram of the working state of this utility model;
[0026] Figure 5-8 This is a schematic diagram of the usage state of this utility model.
[0027] Wherein: 10, fixed seat; 101, side wall; 102, outer end wall; 103, receiving groove; 11, groove; 111, rear end face; 112, front end face; 113, first notch; 114, second notch; 12, through groove; 13, cover plate; 20, movable seat; 201, rotating end; 202, free end; 203, end face; 21, guide groove; 211, first side wall; 212, second side wall; 213, guiding part; 214, rear end wall; 215, front end wall; 22, locking groove; 221, baffle wall; 222, inclined guide wall; 30, locking element; 31, locking pin; 32, rotating part; 33, locking end; 40, spring; 50, rotating shaft. Detailed Implementation
[0028] The present invention will now be further described in conjunction with the accompanying drawings and specific embodiments. It should be noted that, without conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments. Unless otherwise specified, the materials and equipment used in this embodiment are all commercially available. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.
[0029] In the description of this application, it should be understood that the terms "upper," "lower," "front," "rear," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this application. In the description of this application, "a plurality of" means two or more, unless otherwise precisely specified.
[0030] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "connected," "linked," and "connected" should be interpreted broadly. For example, they can refer to a fixed connection, a connection through an intermediary, or a connection within two elements or an interaction between two elements. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.
[0031] like Figure 1 , 2As shown in Figures 3 and 4, this utility model discloses a front-to-back swing adjustment mechanism, specifically a front-to-back swing adjustment mechanism for a lumbar support assembly on a seat. It includes a fixed seat 10, a movable seat 20, a locking element 30, and a spring 40. The fixed seat 10 is mounted on the backrest support of the seat, and the lumbar support assembly is mounted on the movable seat 20. The movable seat 20 includes a rotating end 201 and a free end 202 opposite to the rotating end 201. The rotating end 201 is pivotally connected to the fixed seat 10 via a pivot 50, allowing the movable seat 20 to swing back and forth relative to the fixed seat 10. Consequently, the free end 202 of the movable seat 20 can swing back and forth relative to the fixed seat 10, meaning the lumbar support assembly mounted on the movable seat 20 can swing back and forth relative to the backrest support of the seat. The locking element 30 limits the degree of freedom of the movable seat 20 relative to the fixed seat 10.
[0032] Specifically, a guide groove 21 extending in the front-rear direction is provided on the free end 202 of the movable seat 20. The guide groove 21 includes a first sidewall 211 and a second sidewall 212 opposite to the first sidewall 211. A plurality of locking grooves 22 recessed away from the second sidewall 212 are provided on the first sidewall 211. The plurality of locking grooves 22 are arranged sequentially from front to back starting from the front end of the guide groove 21. The rear end of the guide groove 21 forms a rear end wall 214, which connects to the first sidewall 211 and the second sidewall. Between the rear ends of 212, the rear end of the guide groove 21 forms a blind end, and the front end of the guide groove 21 forms a front end wall 215. The front end wall 215 connects between the front ends of the first side wall 211 and the second side wall 212, so that the front end of the guide groove 21 forms a blind end. The foremost locking groove 22 connects to the front end wall 215, and the last locking groove 22 is spaced a certain distance from the rear end wall 214. The part of the guide groove 21 located between the rear end wall 214 and the last locking groove 22 forms a guide section 213.
[0033] A locking part is provided on the fixed base 10, and a locking member 30 is installed on the fixed base 10. A locking pin 31 is provided on the locking member 30 that extends into the guide groove 21. After the locking member 30 is installed on the fixed base 10, the locking member 30 is configured to be able to move relative to the fixed base 10 in the front-back direction and to swing relative to the fixed base 10 in the left-right direction.
[0034] Specifically, the locking member 30 can move back and forth between a first position located rearward relative to the fixed base 10 and a second position located forward relative to the fixed base 10. At the same time, the locking member 30 can swing between a third position located to the right relative to the fixed base 10 and a fourth position located to the left relative to the fixed base 10. The locking part on the fixed base 10 is used to lock the left and right swinging freedom of the locking member 30. When the locking member 30 is in the first position, the locking member 30 is separated from the locking part on the fixed base 10. At this time, the locking member 30 is not locked by the locking part, so that the locking member 30 has the left and right swinging freedom between the third and fourth positions. When the locking member 30 is in the second position, the locking member 30 is engaged with the locking part, and the locking part limits the left and right swinging freedom of the locking member 30, so that the locking member 30 can be held in the fourth position.
[0035] In other words, when the locking member 30 is in the first position, the locking member 30 has the freedom to swing left and right, and it can swing between the third position and the fourth position. When the locking member 30 is in the second position, the locking member 30 is limited by the locking part, so that the locking member 30 is held in the fourth position.
[0036] Spring 40 is disposed between fixed base 10 and locking member 30. It is used to apply elastic stress to locking member 30, so that locking member 30 always tends to swing toward the third position. That is, when locking member 30 is in the first position, since the degree of freedom of left and right swing of locking member 30 is not limited by locking part, the elastic stress of spring 40 can make locking member 30 be in the third position. When locking member 30 swings between the third position, locking pin 31 on it can swing between guide groove 21 and one of the locking grooves 22. That is, when locking member 30 is in the third position, locking pin 31 is placed in one of the locking grooves 22. Based on the elastic stress of spring 40, locking pin 31 can be kept in the state of being in one of the locking grooves 22. When locking member 30 is in the fourth position, locking member 30 swings to the left by a certain angle relative to its state when it is in the third position, so that locking pin 31 on it disengages from locking groove 22 and is placed in guide groove 21.
[0037] The guide portion 213 in the guide groove 21 guides the locking pin 31, so that when the locking pin 31 is located in the guide portion 213, the locking member 30 is in the fourth position. When the movable seat 20 swings forward until the locking pin 31 slides into the guide portion 213, the guide portion 213 restricts the locking pin 31, thereby restricting the locking member 30 in the fourth position. When the movable seat 20 continues to swing forward until the rear end wall 214 contacts the locking pin 31, the rear end wall 214 abuts against the locking pin. 31. As the movable seat 20 continues to swing forward, the rear end wall 214 will push the locking pin 31 forward, causing the locking member 30 to move forward from the first position to the second position. When the movable seat 20 swings backward until the front end wall 215 contacts the locking pin 31, the front end wall 215 abuts against the locking pin 31. As the movable seat 20 continues to swing backward, the front end wall 215 will push the locking pin 31 backward, causing the locking member 30 to move backward from the second position to the first position.
[0038] The aforementioned locking groove 22 includes a baffle 221 extending from the first sidewall 211 of the guide groove 21 in a direction away from the second sidewall 212, and an inclined guide wall 222 extending obliquely from the end of the baffle 221 away from the second sidewall 212 to the first sidewall 211. When the locking member 30 is in the third position, the locking pin 31 is placed in the locking groove 22, and the front end of the locking pin 31 abuts against the baffle 221. Since the extension direction of the baffle 221 is perpendicular to the extension direction of the guide groove 21, the locking pin 31 and the baffle 221 cooperate to limit the degree of freedom of the baffle 221 to move backward relative to the locking member 30, thereby limiting the degree of freedom of the movable seat 20 to swing backward relative to the fixed seat 10. At this time, the lumbar pillow assembly is subjected to the backward pressure from the user. When force is applied, the pressure is transmitted to the fixed seat 10 via the locking member 30, based on the support of the locking pin 31 on the stop wall 221. This allows the lumbar support assembly to provide stable support for the user. When the locking member 30 is in the third position, if the movable seat 20 is pulled forward by an external force, the movable seat 20 swings forward. The inclined guide wall 222 in the locking groove 22 pushes the locking pin 31 into the guide groove 21, causing the locking member 30 to swing from the third position to the fourth position. In this way, the locking pin 31 can disengage from the locking groove 22. That is, the locking groove 22 and the locking pin 31 cooperate to form a one-way mechanism. When the locking pin 31 is in the locking groove 22, the movable seat 20 can only swing forward and cannot swing backward. Figure 4 In the usage state shown, when the locking pin 31 is located in one of the slots 22, the movable seat 20 can stably support the user's waist backward pressure.
[0039] exist Figure 4 In the indicated usage state, if the lumbar support assembly is positioned too far back and needs to be adjusted forward, the movable seat 20 can be pulled forward to engage the locking pin 31 of the locking member 30 into the corresponding slot 22. (See also...) Figure 4-8 As shown, in Figure 4 In the indicated usage state, if the lumbar support assembly is positioned too far forward and needs to be adjusted backward, the movable seat 20 can be pulled forward. Figure 5 As shown, when the locking pin 31 disengages from the last side of the locking groove 22, the locking pin 31 will slide into the guide part 213 of the guide groove 21. At this time, the locking member 30 is in the first position in the front-back direction and in the fourth position in the left-right direction.
[0040] Then as Figure 6 As shown, continue pulling the movable seat 20 forward. The locking pin 31 contacts the rear end wall 214 and is pushed forward by the rear end wall 214. Since the locking pin 31 is confined in the guide part 213 at this time, it will not swing left and right. Therefore, when the rear end wall 214 pushes the locking pin 31 forward, the locking pin 31 will not fall into the locking groove 22. Continue pulling the movable seat 20 forward to the limit position. The locking pin 31 is pushed forward until the locking member 30 engages with the locking part on the fixed seat 10. At this time, the locking member 30 is in the second position in the front-back direction and in the fourth position in the left-right direction. It is confined in the fourth position by the locking part and the locking member 30. Figure 7 As shown, push the movable seat 20 backward until the front wall 215 of the guide groove 21 contacts the locking pin 31. (See figure) Figure 8 As shown, continue to push the movable seat 20 backward, and the front wall 215 will push the locking pin 31 forward a certain distance, so that the locking member 30 moves forward from the second position to the first position. Since the locking member 30 is no longer limited by the locking part at this time, based on the elastic stress of the spring 40, the locking member 30 swings from the fourth position to the third position. At this time, the locking pin 31 on the locking member 30 falls into the frontmost slot 22. Finally, according to the required position of the lumbar pillow assembly, swing the movable seat 20 forward appropriately so that the locking pin 31 falls into the corresponding slot 22, and the front and back adjustment of the lumbar pillow assembly can be completed.
[0041] Compared to existing technologies, the forward and backward swing adjustment mechanism of this utility model can provide stable support for the user's body, prevent the seat support unit from shifting backward abnormally, and when it is necessary to adjust the forward and backward position of the support unit, the user can adjust the support unit by pushing it forward or backward with one hand, which is simple and convenient.
[0042] It should be noted that this utility model utilizes the rear end wall 214 of the guide groove 21 as a toggle part. When the rear end wall 214 contacts the locking pin 31, it pushes the locking pin 31 forward. The front end wall 215 of the guide groove 21 serves as another toggle part. When the front end wall 215 contacts the locking pin 31, it pushes the locking pin 31 backward, thereby enabling the locking member 30 to move back and forth between the first and second positions. The components on the movable seat 20 used to toggle the locking pin 31 are not limited to the aforementioned rear end wall 214 and front end wall of the guide groove 21. 215, for example, a protrusion may be provided on the locking member 30 and two protrusions may be provided on the movable seat 20. When the movable seat 20 moves forward to the limit position, one of the protrusions pushes the protrusion, causing the locking member 30 to move forward. When the movable seat 20 moves backward to the limit position, the other protrusion pushes the protrusion, causing the locking member 30 to move backward. The guide part 213 is not necessarily formed by a part of the guide groove 21. It may also be other parts on the movable seat 20 used to move the protrusion so that the locking member 30 can swing.
[0043] In order to enable the locking post 31 to be able to be Figure 7 Change to Figure 8 During the process, it smoothly falls into the foremost locking groove 22, connecting the baffle 221 of the foremost locking groove 22 with the front end wall 215, and ensuring that the two are flush with each other. In this way, after the locking member 30 disengages from the locking part on the fixed base 10, the locking pin 31 can swing from the foremost position of the guide groove 21 and fall into the foremost locking groove 22.
[0044] The locking pin 31 is configured to have a long cross-section. After the locking pin 31 slides into the guide part 213, the locking pin 31 is guided by the first side wall 211 of the guide groove 21, so that the length direction of the cross-section of the locking pin 31 is consistent with the extension direction of the guide groove 21, thereby allowing the locking member 30 to swing from the third position to the fourth position.
[0045] The fixed base 10 includes two side walls 101 and an outer end wall 102. The two side walls 101 are arranged opposite to each other, and the outer end wall 102 is located between the ends of the two side walls 101 away from the free end 202 of the movable base 20. The two side walls 101 and the outer end wall 102 together form a receiving groove 103. The receiving groove 103 has an opening at the front and is used to receive the movable base 20. The rotating end 201 of the movable base 20 is pivotally connected to the ends of the two side walls 101 away from the outer end wall 102 by a pivot 50. The pivot 50 can be a locking screw to facilitate the installation of the movable base 20 on the fixed base 10. The guide groove 21 is formed on the end face 203 of the free end 202 of the movable base 20. The locking member 30 is installed on the outer end wall 102 of the fixed base 10. Specifically, a groove 11 is provided on the outer end wall 102, which is recessed from its outer surface to its inner surface. A through groove 12 extending to the inner surface of the outer end wall 102 is provided on the bottom surface of the groove 11. The locking member 30 is placed in the groove 11, and the locking pin 31 passes through the through groove 12 and is embedded in the guide groove 21.
[0046] A first recessed notch 113 is provided on the rear end face 111 of the groove 11, and a second recessed notch 114 is provided on the front end face 112 of the groove 11, forming the aforementioned locking part; correspondingly, a rotating part 32 is formed at the rear end of the locking member 30, and a locking end 33 is formed at the front end. The rotating part 32 is embedded in the first notch 113, allowing the rotating part 32 to rotate within the first notch 113, thereby allowing the locking member 30 to swing left and right between the third and fourth positions. When the locking member 30 is in the second position, such as Figure 7 As shown, the rotating part 32 is placed in the first notch 113, and the locking end 33 is placed in the second notch 114. When the front end wall 215 pushes the locking pin 31 backward, the locking end 33 can disengage from the second notch 114, causing the locking member 30 to move to the first position. At the same time, the elastic stress of the spring 40 is used to make the locking member 30 swing to the third position.
[0047] In this utility model, the outer end wall 102 of the fixed seat 10 is arc-shaped, and the end face 203 of the free end 202 of the movable seat 20 is also arc-shaped. The centers of the arc of the outer end wall 102 and the arc of the end face 203 both fall on the central axis of the rotating shaft 50.
[0048] To facilitate the installation of the locking element 30 and the spring 40, a cover plate 13 is detachably fixed on the outer end wall 102. The cover plate 13 is placed outside the groove 11 and covers the outside of the locking element 30.
[0049] It should be noted that the spring 40 of this utility model is used as an elastic element to apply elastic stress to the locking element 30 so that the locking element 30 always maintains the tendency to swing toward the third position. It can prevent the locking pin 31 of the locking element 30 from disengaging from the locking groove 22. In other embodiments, other elastic elements such as tension springs or elastic rubber blocks can be used to replace the spring 40.
[0050] The above example only illustrates the fore-and-aft swing adjustment mechanism of this utility model using the lumbar support assembly of a seat. The fore-and-aft swing adjustment mechanism of this utility model is also applicable to the headrest assembly, backrest assembly, etc. of a seat.
[0051] The seat of this utility model includes the aforementioned fore-and-aft swing adjustment mechanism. The other structures of the seat are the same as those in the prior art and will not be described in detail here.
[0052] Finally, it should be noted that the above embodiments are only optional embodiments of this utility model and should not be used to limit the scope of protection of this utility model. Any non-substantial changes and substitutions made by those skilled in the art based on this utility model shall fall within the scope of protection claimed by this utility model.
Claims
1. A back-and-forth swing adjustment mechanism, characterized in that, Includes fixed base, movable base, and locking components; The movable seat includes a rotating end and a free end opposite to the rotating end. The rotating end is pivotally connected to the fixed seat so that the free end can swing back and forth relative to the fixed seat. The free end of the movable seat is provided with a guide groove extending in the front-to-back direction. The guide groove includes a first side wall and a second side wall opposite to the first side wall. The first side wall is provided with a plurality of locking grooves recessed away from the second side wall. The plurality of locking grooves are arranged sequentially from front to back. The movable seat is provided with a guiding part, a first actuating part connected to the rear end of the guiding part, and a second actuating part located at the end of the plurality of locking grooves away from the first actuating part. The fixed base is provided with a locking part, the locking member is installed on the fixed base and is provided with a locking pin extending into the guide groove. The locking member is installed on the fixed base and is configured to be able to move back and forth between a first position and a second position, and to swing left and right between a third position and a fourth position. When the locking member is in the first position, it has the freedom to swing between the third position and the fourth position. When the locking member is in the second position, the locking member cooperates with the locking part on the fixed base to keep the locking member in the fourth position. An elastic element is provided between the fixed base and the locking element. The elastic element is used to apply elastic stress to the locking element so that the locking element always maintains the tendency to swing toward the third position. When the locking member is in the third position, the locking pin is engaged in one of the slots. When the locking member is in the fourth position, the locking pin disengages from the slot and is placed in the guide groove. The guide part is used to guide the locking pin so that the locking member is in the fourth position. The first actuating part is used to push the locking pin forward when moving forward relative to the locking pin so that the locking member moves from the first position to the second position. The second actuating part is used to push the locking pin backward when moving backward relative to the locking pin so that the locking member disengages from the locking part.
2. The forward and backward swing adjustment mechanism as described in claim 1, characterized in that, The locking groove includes a baffle extending from the first sidewall of the guide groove toward the direction away from the second sidewall, and an inclined guide wall extending from the end of the baffle away from the second sidewall toward the first sidewall. When the locking member is in the third position, the locking pin abuts against the baffle. The inclined guide wall is used to push the locking pin toward the fourth position when the free end of the movable seat moves forward relative to the fixed seat.
3. The forward and backward swing adjustment mechanism as described in claim 2, characterized in that, The guide groove includes a rear end wall connected between the rear ends of the first side wall and the second side wall, and a front end wall connected between the front ends of the first side wall and the second side wall. The rear end wall forms a first actuating part, and the front end wall forms a second actuating part. The part between the last side of the guide groove and the rear end wall forms a guiding part. The baffle of the frontmost side of the positioning groove is connected to the front end wall and is flush with each other.
4. The forward and backward swing adjustment mechanism as described in claim 3, characterized in that, The locking post has a long, narrow cross-section.
5. The forward and backward swing adjustment mechanism as described in claim 1, characterized in that, The fixed seat includes two side walls and an outer end wall located between the ends of the two side walls away from the free end of the movable seat. The two side walls and the outer end wall together form a receiving groove with a front opening for accommodating the movable seat. The rotating end of the movable seat is pivotally connected to the ends of the two side walls away from the outer end wall via a pivot shaft. A guide groove is opened on the end face of the free end of the movable seat.
6. The forward and backward swing adjustment mechanism as described in claim 5, characterized in that, A groove is provided on the outer end wall, which is recessed from its outer surface to its inner surface. A through groove is provided on the bottom surface of the groove, extending to the inner surface of the outer end wall. The locking member is placed in the groove, and the locking pin is inserted into the guide groove after passing through the through groove.
7. The forward and backward swing adjustment mechanism as described in claim 6, characterized in that, The rear end face of the groove is provided with a first recessed notch, and the locking part is a second recessed notch located on the front end face of the groove. The rear end of the locking member forms a rotating part and the front end forms a locking end. The rotating part is embedded in the first notch so that the locking member can swing left and right between the third position and the fourth position. When the locking member is in the second position, the rotating part is placed in the first notch and the locking end is placed in the second notch.
8. The forward and backward swing adjustment mechanism as described in claim 7, characterized in that, The outer end wall of the fixed seat and the end face of the free end of the movable seat are both arc-shaped.
9. The forward and backward swing adjustment mechanism as described in claim 5, characterized in that, A cover plate is detachably fixed to the outer end wall, the cover plate is placed outside the groove and covers the outside of the locking element.
10. A seat, characterized in that, Includes the forward and backward swing adjustment mechanism as described in any one of claims 1-9.