Vehicle seat lock

Abstract

Vehicle seat lock, comprehensive a lock housing (1) with a base plate (2) connected to the seat, a ratchet (3) which is rotatably mounted in the lock housing (1) on the base plate (2) about a ratchet pin (4) from an open position to a closed position and has a recess (5) for engagement with a bracket (21) which is connected to a fixed part of the body, and a pawl (7) which is rotatably mounted on the base plate (2) about a pawl pin (8) in the opposite direction of rotation to the ratchet (3) from a locking position to an unlocking position and interacts with the ratchet (3), characterized by the fact that a cam (11) is rotatably mounted on the base plate (2), which is pivotable to engage with a first engagement arm (13) of a two-armed backlash compensation lever (14), wherein the two-armed backlash compensation lever (14) is rotatably mounted about a support pin (15) which is fixedly connected to the base plate (2), wherein a second backlash compensation arm (16) of the two-armed backlash compensation lever (14) is in force-fit contact with the bracket (21) in the closed position of the ratchet (3) in a direction which is substantially perpendicular to a lateral contact surface (5a) of the recess (5), and wherein the cam (11) or the pawl (7) is provided with a projection for the pawl (7) to engage with the cam (11) when the pawl (7) moves from the locking position to the unlocking position.

Description

field of technology

[0001] The invention relates to a vehicle seat lock comprising a lock housing with a base plate connected to the seat, a ratchet rotatably mounted in the lock housing on the base plate about a ratchet pin, which is provided with a recess for engagement with a bracket connected to a fixed part of the body and is rotatable from an open position to a closed position against the force of a ratchet spring, and a pawl rotatably mounted on the base plate about a pawl pin, which is rotatable in the opposite direction to the ratchet against the force of a pawl spring from a locking position to an unlocking position and cooperates with the ratchet. State of the art

[0002] A vehicle seat lock is typically located in the seat back and serves to engage or release a retaining element that is permanently attached to the vehicle body. This allows the seat back to be locked in one or more selected positions, secured in the selected position, and released again as needed. The retaining element, which is attached to the vehicle body, is engaged in the catch recess of the ratchet, which is rotatably mounted in the lock. The ratchet's catch recess is U-shaped, with its legs tapering from the opening towards the base of the recess. If the ratchet recess has a U-shape that does not taper significantly, the retaining element must have a diameter sufficiently smaller than the width of the recess to ensure that the ratchet can reliably engage the retaining element.After the locking element engages in the ratchet's recess, some play remains between the locking element and the recess walls, causing the seat back to pivot relative to the vehicle body. This play manifests as vibrations and rattling or knocking noises while driving.

[0003] From an internal source, the applicant is aware of a solution from invention application PV 2024-121, according to which a lock for securing a swiveling seat backrest of a vehicle comprises two ratchets which are coaxially and pivotably mounted in the lock housing on a bearing pin against the force of torsion springs between a closed position and an open position, wherein the ratchets have catch recesses for engaging a catch element of a fixed part of the vehicle body. The bearing pin of the ratchets extends through the bearing ends of the ratchets. Side walls of the catch recesses of the first ratchet that are further away from the bearing pin have a radial distance from the bearing pin that increases towards the bottom of the catch recesses. Side walls of the catch recesses of the first ratchet that are closer to the bearing pin have a radial distance from the bearing pin that decreases towards the bottom of the catch recesses.The side walls of the catch recesses of the second ratchet, closer to the pivot pin and those further away, can be adjusted relative to each other by moving the ratchets relative to one another. The physical design of the ratchet catch recesses causes the catch element to self-lock between opposing walls of the ratchet catch recesses when the ratchets are closed. While this solution eliminates play in the catch element within the ratchet catch recesses, it requires two ratchets and technically complex components, making the vehicle seat lock complex and expensive to manufacture.

[0004] A vehicle seat lock for eliminating play between the seat and the vehicle body is known from publication KR 2015 005 0064. The lock comprises a ratchet, which is rotatably mounted around a ratchet shaft and acted upon by a clockwise torsion spring, and a pawl, which is rotatably mounted around a pawl pin and acted upon by a counterclockwise torsion spring. The ratchet has a recess in its first section for engagement with a shackle and, in a subsequent second section, two radial projections for engagement with the pawl. In the closed position, the shackle is held by the ratchet, which is blocked against opening by the pawl. When closing, a projection of the ratchet and an engagement surface of the pawl engage first, forming a first locking section.The pawl spring pushes the pawl further counterclockwise, causing a projection on the pawl to engage with a ratchet surface. The continued movement of the pawl forces the ratchet into the closed position against the force of the ratchet spring, pulling the shackle inwards into the lock and gradually creating a gap in the first locking section. The play between the seat and the vehicle is reduced because the lock pulls the shackle with such force that the shackle either rests firmly against the lower projection of the ratchet, pressing the seat into its mounting elements, or the shackle is supported against the lock's base plate, preventing any relative movement of the seat against the vehicle.The elimination of play between the seat and the bodywork is thus ensured, however, the elimination of play in the bracket within the recess of the ratchet itself is not guaranteed. Subject matter of the invention

[0005] The disadvantages of the prior art are substantially eliminated, and the object of the invention is solved by a vehicle seat lock comprising a lock housing with a base plate connected to the seat, a ratchet rotatably mounted in the housing on the base plate about a ratchet pin, which is rotatable from an open position to a closed position, has a recess for engaging with a shackle connected to a fixed part of the bodywork and is rotatable against the force of a ratchet spring, and a pawl rotatably mounted on the base plate about a pawl pin, which is rotatable in the opposite direction to the ratchet against the force of a pawl spring from a locked position to an unlocked position and interacts with the ratchet, wherein the solution according to the invention is characterized in that a cam is rotatably mounted on the base plate.which is rotatable by the force of a cam spring in engagement with a first engagement arm of a two-armed backlash compensating lever, wherein the backlash compensating lever is rotatably mounted about a support pin fixedly connected to the base plate, wherein a second backlash compensating arm of the two-armed backlash compensating lever is in frictional contact with the bracket in the closed position of the ratchet in a direction that is substantially perpendicular to a lateral contact surface of the recess, and wherein the cam or the pawl is provided with a projection for the pawl to engage with the cam when the pawl moves from the locked position to the unlocked position.

[0006] Advantageously, the projection can be formed by a pin that is rigidly connected to an arm of the cam. Advantageously, a preload spring can be arranged between the second backlash-compensating arm of the backlash-compensating lever and the ratchet. Advantageously, the cam can be rotatably mounted on the pawl pin. Explanation of the drawings

[0007] The vehicle seat lock according to the invention is shown in the drawings, wherein Fig. 1 shows a cross-section through the lock in the locked position Fig. Figure 2 shows a cross-section through the lock in the unlocked position. Exemplary embodiments of the invention

[0008] According to Fig. In the figure 1, the vehicle seat lock is arranged in a housing 1, wherein a ratchet 3 is rotatably mounted on the base plate 2 of the housing, which is connected to the seat, about a ratchet pin 4 and can be rotated from an open position to the closed position shown against the force of a preload spring 19. The ratchet 3 is provided with a conventional recess 5 for gripping and engaging a shackle 21, which is connected to a fixed part of the body. A pawl 7 is rotatably mounted on the base plate 2 about a pawl pin 8, which can pivot from the locked position shown to an unlocked position and, in the locked position, engages in a stop (not shown) on the ratchet 3. The pawl 7 can be rotated from the locked position to the unlocked position in the opposite direction to the rotation of the ratchet 3 against the force of a pawl spring (not shown).A cam 11 is rotatably mounted on the base plate 2, preferably on the pawl pin 8. The cam 11 has a support arm 11a that terminates in a shaped contact surface 11b. A two-armed backlash compensation lever 14 is rotatably mounted on the base plate 2 about a support pin 15, with a radial first engagement arm 13 and a radial second backlash compensation arm 16. The cam 11 can be engaged by the force of a cam spring 12, with the support arm 11a interacting with an engagement surface 13a formed on the first engagement arm 13 of the backlash compensation lever 14.Due to the force exerted by the support arm 11a on the first engagement arm 13, a backlash compensation surface 16a of the second backlash compensation arm 16 of the backlash compensation lever 14 is in force-fit contact with the bracket 21 in the closed position of the ratchet 3, in a direction that is essentially perpendicular to a lateral contact surface 5a of the recess 5. A system consisting of a cam 11 and a backlash compensation lever 14 is used to compensate for backlash in the bracket 21 within the recess 5 of the ratchet 3. The cam 11 is mounted on the axis of rotation of the pawl pin 8 of the pawl 7. The backlash compensation lever 14 pivots about the support pin 15, which is fixedly connected to the base plate 2. The cam 11 has a specially designed contour that is in contact with the backlash compensation lever 14. The cam 11 is constantly acted upon by the spring force of the cam spring 12 in the direction of engagement with the play compensation lever 14.This causes the play-compensating lever 14 to be in force-fit contact with the shackle 21 and to press it against the wall of the recess 5 of the ratchet 3, thereby achieving permanent play compensation of the shackle 21 in all its positions within the recess 5 of the ratchet 3. This eliminates any play between the lock itself and the shackle 21. The shackle 21 is released when the locking pawl 7 is pivoted upwards by means of a handle, and also when the cam 11 is lifted via a pin 18, which is advantageously an integral part of the cam 11. The ratchet 3 and the play-compensating lever 14 share a common preload spring 19, which permanently preloads both components. When opening, the ratchet 3 rotates into the open position due to the preload spring 19.The cam 11 or the pawl 7 is provided with a projection for engaging the pawl 7 with the cam 11 when the pawl 7 moves from the locked position to the unlocked position. The purpose of the projection is that, when the pawl 7 moves out of engagement with the ratchet 3, the first engagement arm 13 is released. The force of the preload spring 19 releases the first engagement arm 13 as soon as the pawl 7 disengages from the ratchet 3. The projection can advantageously be formed by the pin 18, which is fixedly connected to an arm of the cam 11.

[0009] According to Fig.Figure 2 shows the vehicle seat lock in the open position. When the ratchet 3 pivots around the ratchet pin 4 into the open position, it releases the lever 21, and the seat with the lock can be folded down. When the ratchet 3 opens and the lever 21 is released, the force exerted by the lever 21 on the end face of the play-compensating surface 16a of the second play-compensating arm 16 ends, and the spring force of the preload spring 19 causes the play-compensating lever 14 to return to a starting position in which the first engagement arm 13 rests against a stop 1a of the housing 1. The pawl 7 abuts the pin 18, which is connected to the support arm 11a of the cam 11. In the open position of the lock, the locking pawl 7 is disengaged from the ratchet 3, and there is play between the engagement surface 13a of the first engagement arm 13 and the contact surface 11b of the cam 11. Industrial applicability

[0010] The vehicle seat lock according to the invention can be used in particular in the seat back of a motor vehicle. Reference symbol list 1 case 1a attack 2 Base plate 3 ratchets 4 ratchet pins 5 Exclusion 5a Side wall ratchet spring 7 Locking pawl 8 locking pawl pins 11 cam 11a Support arm 11b Plant area 12 Cam spring 13 first intervention arm 13a Intervention area 14 Play compensation levers 15 support pins 16 second equalizer arm 16a Frontal play compensation surface 17 lead 18 bolts 19 Preload spring 21 irons QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] KR 2015 005 0064

[0004]

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