JP4958521B2 - Reaction force adjusting method and mechanism for locking mechanism - Google Patents

Description

  The present invention relates to a reaction force adjustment method and mechanism for a locking mechanism that swings a supported member with respect to a support member. More specifically, the present invention relates to a reaction force adjusting method and mechanism suitable for use in a chair locking mechanism.

  As a conventional locking mechanism that makes it possible to tilt the seat and back of the chair back and forth, for example, as shown in FIG. 5, the front seat frame 101 fixed to the leg 106 and swingable with respect to the leg 106 are possible. A rear seat frame 102 and a reaction force applying mechanism 107 that is interposed between the frames 101 and 102 and applies a force to return the rear seat frame 102 to the initial position by pushing the lower end backward. There is a thing (patent document 1). In this conventional locking mechanism, the reaction force applying mechanism 107 is rotatably connected to the front seat frame 101 and the rear seat frame 102 via spring mounts 108 at both ends, using the compression coil spring 104 as a reaction force source. ing. Both spring mounts 108 are connected by passing through the connecting shafts 109 and 110 in a state where the holes of both seat frames 101 and 102 and the holes of the spring mount 108 are aligned. In this chair, when a seated person applies a load to the seat 103 and the backrest 105, the rear seat frame 102 tilts backward against the reaction force applying mechanism 107, thereby enabling locking.

JP 2000-139604 A

  However, in the conventional locking mechanism disclosed in Patent Document 1, the magnitude of the reaction force caused by the compression coil spring 104 when a load is applied to the seat 103 or the backrest 105 is constant, and the reaction force of the locking operation is reduced. The user cannot adjust the size appropriately. For this reason, if a compression coil spring having a weak reaction force is used, the backrest 105 will easily come into contact with the last part when a heavy weight person sits down, and the reaction force is strong. When the compression coil spring is used, the rocking operation becomes heavy, and a large force is required to tilt the backrest 105 when a light weight person sits down. For this reason, it is difficult to say that a comfortable user experience can be provided according to the attributes and preferences of the user.

  In addition, the reaction force of the coil spring is greatly different between when the coil spring is expanded and contracted small and when it is expanded and contracted greatly. The conventional locking mechanism disclosed in Patent Document 1 uses the compression coil spring 104 as a reaction force source for the locking operation. Therefore, the reaction force differs greatly between when the locking is shallow and when the locking is deep, and the reaction force of a certain size. It is hard to say that comfortable use is realized by supporting the seated person with force.

  Thus, the present invention can easily adjust the magnitude of the reaction force of the locking operation of the supported member that is swingably connected to the support member, and can exhibit an appropriate reaction force for a wide range of loads. Another object of the present invention is to provide a locking mechanism reaction force adjusting method and mechanism that can reduce the change in the magnitude of the reaction force according to the degree of locking.

  In order to achieve such an object, the reaction force adjusting method for a locking mechanism according to claim 1 connects the support member and the supported member so as to be swingable, and interposes a fluid spring between the support member and the supported member. The support member or the supported member and the fluid spring are moved to change the angle between the supported member and the fluid spring at the initial position to move the supported member to the initial position. The magnitude of the reaction force of the fluid spring biased to the position is adjusted.

  According to a second aspect of the present invention, there is provided a reaction force adjusting mechanism for a locking mechanism comprising: a support member; a supported member that is swingably connected to the support member; one end is rotatably connected to the support member; A fluid spring rotatably connected to the supported member, and a connecting shaft moving means for moving the connecting shaft of the supporting member or the supported member and the fluid spring are provided.

  Therefore, according to the reaction force adjusting method and mechanism for the locking mechanism, the angle between the supported member and the fluid spring is changed by moving the connecting shaft center of the supporting member or the supported member and the fluid spring. Therefore, the force acting in the direction to return the supported member to the initial position changes, and the apparent magnitude of the reaction force of the fluid spring that urges the supported member relative to the support member is adjusted.

  Further, the fluid spring has a small change in the magnitude of the reaction force when it is expanded and contracted small and when it is expanded and contracted greatly, that is, when the rocking is shallow and deep. Therefore, according to the first and second aspects of the invention, since the fluid spring is used as a reaction force source for urging the supported member, the magnitude of the reaction force is kept almost constant regardless of the degree of locking. It is.

  Furthermore, in the case of a coil spring, it is necessary to incorporate it while being compressed in order to obtain an appropriate reaction force after installation. On the other hand, a fluid spring generates a predetermined load even when it is fully extended. It is possible to make the installation work easier.

  According to a third aspect of the present invention, in the reaction force adjusting mechanism for the locking mechanism according to the second aspect, the fluid spring incorporates a piston in the cylinder, and the spaces on both sides of the piston in the cylinder are communicated with each other by a communication path. It is made to have a structure. In the case of the fluid spring having this structure, the magnitude of the reaction force exerted regardless of the position of the piston, that is, regardless of the degree of expansion / contraction of the fluid spring, is kept substantially constant. Therefore, a substantially constant reaction force is exhibited regardless of the degree of locking.

  According to a fourth aspect of the present invention, in the reaction force adjusting mechanism for the locking mechanism according to the second or third aspect, the connecting shaft center moving means is configured to connect the connecting shaft center to the support member or the supported member and the fluid spring. Is moved on an arc centered on the connection center opposite to the connection axis. In this case, when moving the connecting shaft center of the fluid spring, the length of the fluid spring is kept constant and does not change. You can move easily.

  According to a fifth aspect of the present invention, in the reaction force adjusting mechanism for a locking mechanism according to any of the second to fourth aspects, the supported member is maximally swung from the initial position with respect to the supporting member. In the projection onto the plane orthogonal to the rotation axis, the angle formed by the direction from the center of rotation of the supported member toward the point of action of the fluid spring with respect to the supported member and the extension direction of the fluid spring is 60 degrees or less. I am doing so. Here, the force (hereinafter referred to as an effective reaction force) that causes the fluid spring to return the supported member to the initial position is proportional to sin θ ′ when the angle is θ ′. Therefore, the range of change in the effective reaction force can be increased in the case of changing in the range close to 0 degrees compared to the case of changing in the range close to 90 degrees. For example, sin 65 ° is about 0.91 and sin 90 ° is 1.00. Therefore, when the angle θ ′ is changed in the range of 65 to 90 degrees, the effective reaction force is reduced. It can only be changed about 1.1 times. On the other hand, since sin5 ° is about 0.087 and sin30 ° is about 0.42, when the angle θ ′ is changed in the range of 5 to 30 degrees, The effective reaction force can be changed by about 5 times within the same range of 25 degrees. For this reason, in the case of the invention described in claim 5, the change width of the effective reaction force of the fluid spring can be increased.

  According to the reaction force adjusting method and mechanism for a locking mechanism according to claim 1 and 2, since the size of the angle formed by the supported member and the fluid spring can be changed, the supported member is urged against the supporting member. It is possible to adjust the apparent magnitude of the reaction force of the fluid spring, and to ensure a comfortable feeling by demonstrating an appropriate reaction force for a wide range of loads according to the user's attributes, preferences or usage. can do. In addition, the apparent magnitude of the reaction force of the fluid spring that biases the supported member can be adjusted simply by moving the connecting axis of the fluid spring. An adjustment mechanism can be configured, and manufacturing effort and cost can be reduced. And by adjusting the reaction force by changing the angle of the fluid spring, the operating force required for adjustment can be reduced compared to the case of adjusting the reaction force by expanding and contracting the coil spring, thereby improving operability. In addition, the reaction force adjustable range can be expanded.

  In addition, since the magnitude of the reaction force can be kept almost constant regardless of the degree of locking, when the reaction force adjusting method and mechanism for the locking mechanism is used for a locking mechanism of a chair, for example, the posture is Even when it changes, it is possible to support the seated person with a reaction force of almost a constant magnitude and improve the comfort of use.

  Furthermore, since the assembly work of the reaction force adjustment mechanism is facilitated, the assembly work can be made efficient.

  Further, according to the reaction force adjusting mechanism for the locking mechanism according to the third aspect, the magnitude of the reaction force exerted regardless of the degree of expansion and contraction of the fluid spring is maintained substantially constant. However, when applied to a rocking mechanism of a chair, for example, when the posture changes, the seated person is always supported by a reaction force of a substantially constant magnitude. The user experience can be improved.

  Further, according to the reaction force adjusting mechanism for the locking mechanism according to the fourth aspect, the connecting shaft center can be easily moved by the connecting shaft center moving means, so that the comfort of use can be improved.

  Further, according to the reaction force adjusting mechanism for the locking mechanism according to the fifth aspect, the change range of the effective reaction force of the fluid spring can be increased, so that an appropriate reaction force is exerted for a wider range of loads. Comfortable comfort can be secured.

  Hereinafter, the configuration of the present invention will be described in detail based on the best mode shown in the drawings.

  FIG. 1 to FIG. 4 show an example of the embodiment of the reaction force adjusting method and mechanism for the locking mechanism of the present invention. In this locking mechanism reaction force adjusting method, the supporting member 2 and the supported member 4 are slidably coupled, and a fluid spring 31 is interposed between the supporting member 2 and the supported member 4, By moving the connecting shaft 29 that connects the fluid spring 31 to change the angle between the supported member 4 and the fluid spring 31 at the initial position, the supported member 4 is moved to the initial position with respect to the supporting member 2. The magnitude of the reaction force of the urging fluid spring 31 is adjusted.

  The locking mechanism reaction force adjusting method is implemented as a locking mechanism reaction force adjusting mechanism of the present invention. The reaction force adjusting mechanism 1 of this embodiment in which the method of the present invention is applied to a chair locking mechanism 6 includes a support member 2, a supported member 4 that is swingably connected to the support member 2, and one end of the support member. 2, a fluid spring 31 that is rotatably connected to the support member 4, and a connecting shaft 29 that moves the connecting shaft 29 that connects the support member 2 and the fluid spring 31. 18.

  The locking mechanism 6 is capable of swinging a synchro frame (also referred to as a swinging member) 4 as a supported member around a rotation shaft 3 at one location with respect to a main frame (also referred to as a base) 2 as a support member. It is something to support. That is, the main frame 2 and the sync frame 4 are connected to each other so as to be swingable by the rotation shaft 3.

  In the present embodiment, a seat 7 (not shown in FIG. 2) is supported above the main frame 2 and the sync frame 4, and a back support that supports a backrest (not shown) on the sync frame 4. A hook 8 is attached.

  The main frame 2 has a bottom plate 2a and left and right outer walls 2b and 2b. Further, the main frame 2 has a gas spring support portion 26 fitted to an upper portion of a leg 25 in which a gas spring is built in an upper end portion. Thereby, the main frame 2 is fixed to the upper part of the leg 25 and the seat 7 is supported via the main frame 2.

  The seat 7 includes, for example, a seat plate serving as a core material, a cushion placed on the seat plate, and an upholstery covering the cushion. The seat 7 is supported by a seat support hole 22 formed in the front end portion of the main frame 2 by a front seat support shaft 23 so that the front portion can be moved back and forth and swingable, and the sync frame 4 is supported by a rear seat support shaft 27. The rear part is supported to be swingable. As a result, the rear portion of the seat 7 moves up and down as the synchro frame 4 swings, and the front portion swings while slightly moving back and forth, and the backrest and the seat 7 perform a locking operation in conjunction with each other.

  The sync frame 4 is formed with a stopper 28 that regulates the swingable angle. The stopper 28 abuts against the upper end surface of the outer wall 2b of the main frame 2 as the sync frame 4 tilts, thereby restricting the sync frame 4 from tilting further and acting on the backrest and the seat 7 at that time. Support the load.

  In the present embodiment, the locking mechanism 6 has a reaction force applying mechanism 5 that urges the synchro frame 4 toward the initial position. The reaction force applying mechanism 5 functions to return the initial position by applying a reaction force to the backrest and the tilt of the seat 7 by urging the front end portion of the synchro frame 4 backward. The state where the front end portion of the sync frame 4 is pushed back fully, that is, the rear side of the sync frame 4 is pulled up fully is the initial position, and FIGS. 1 and 2 show the initial position.

  The reaction force applying mechanism 5 of the present embodiment includes a front spring mount 11 and a rear spring mount 12 that are guided by a sliding shaft 10 and can change the interval, and a spring 9 interposed between the spring mounts 11 and 12. Prepare. The front spring mount 11 and the rear spring mount 12 hold the spring 9 so that it does not buckle when the sync frame 4 is inclined and external force is applied to the reaction force applying mechanism 5 to compress the spring 9. The front spring mount 11 is inserted into a support hole 17 formed at the center of a mount receiving rib 16 integrally formed with the main frame 2 and is supported so as to be slightly movable, that is, with some play. The rear spring mount 12 has an engagement hook 14 at the rear end, and an engagement shaft 15 attached to the front end of the synchro frame 4 enters the engagement hook 14 so that the synchro frame 4 and the rear spring mount 12 are connected. It is rotatably connected.

  The locking mechanism 6 includes a reaction force adjusting mechanism 1 that is interposed between the main frame 2 and the sync frame 4 and that can adjust the magnitude of the reaction force against the tilt of the sync frame 4.

  The reaction force adjusting mechanism 1 of the present embodiment includes a fluid spring 31 that urges the rear end portion of the sync frame 4 upward, and a connecting axis moving means that is interposed between the front end portion of the fluid spring 31 and the main frame 2. 18.

  In the present embodiment, a gas spring is used as the fluid spring 31. The gas spring 31 of this embodiment has a structure in which a piston (not shown) connected to a shaft 31b is built in a cylinder 31a, and spaces on both sides of the piston in the cylinder 31a are communicated by a communication path. With this structure, the gas spring 31 exhibits a reaction force having a substantially constant magnitude regardless of the position of the piston.

  The gas spring 31 includes an operation mechanism 33 on the distal end side of the shaft 31b protruding from the cylinder 31a. Since the operation mechanism of the gas spring and its attachment mode itself are well-known techniques, the details are omitted here (for example, Patent Document 1). The operation mechanism 33 according to the present embodiment includes an operation arm 34 that presses the adjustment pin 32 at the tip of the shaft 31b of the gas spring 31, and an operation arm 34 that is rotatably supported around a shaft portion 39 and is fixed to the gas spring 31. The support frame 35 includes a wire 36 having one end coupled to the operation arm 34 for rotating the operation arm 34, and a tube 37 that slidably accommodates the wire 36. Note that the wire 36 and the tube 37 are not shown in FIG.

  Then, by pulling the other end of the wire 36 and rotating the operation arm 34 and pushing the adjustment pin 32, the valve provided in the communication path in the cylinder 31a is opened, and the gas spring 31 can be expanded and contracted. Can be locked. Further, by loosening the wire 36 and pulling out the adjustment pin 32, the valve is closed and the length of the gas spring 31 is fixed, and the main frame 2, the sync frame 4 and the gas spring 31 form a triangular frame. 4 is locked and cannot be locked.

  The support frame 35 is supported so as to be rotatable with respect to the sync frame 4 about a support shaft 38. Thereby, the gas spring 31 is rotatably connected to the synchro frame 4.

  The connecting shaft moving means 18 includes a fitting arcuate surface 21 formed at the rear ends of both outer walls 2b, 2b of the main frame 2, two pin gears 20 fitted to each of the fitting arcuate surfaces 21, It comprises a connecting shaft 29 that connects the pin gears 20 on both sides, and an arc guide portion 19 that has a long hole 19 a that passes through the connecting shaft 29.

  The fitting arc surface 21 includes an arc section 21b in which the rear ends of both outer walls 2b, 2b of the main frame 2 are cut into an arc shape centering on the support shaft 38 at the initial position, and a recess formed in the arc section 21b. 21a.

  The pin gear 20 is composed of two circular side plates 20a facing each other and pins 20b sandwiched between the side plates 20a and 20a and provided at right angles thereto. A connecting shaft 29 passes through the center of the side plate 20a. The pins 20b are arranged around the connecting shaft 29 with a space therebetween. The pin gear 20 of this embodiment has four pins 20b. The position of the connecting shaft 29 is fixed by fitting the pin 20b into the recess 21a of the fitting arcuate surface 21.

  The gas spring 31 has a cylindrical bearing 31c at the tip. And the through-hole of the bearing part 31c supports the connection shaft 29 so that sliding is possible. Thereby, the gas spring 31 is rotatably connected to the main frame 2. The axis of the connecting shaft 29 is the connecting axis between the main frame 2 and the gas spring 31.

  One end of the connecting shaft 29 extends from the main frame 2 to the vicinity of the position where the seated person sitting on the seat 7 naturally lowers his / her arm. A handle 24 is attached to the end of the connecting shaft 29 that extends greatly from the main frame 2. As described above, the reaction force adjusting mechanism 1 can be easily operated by disposing the handle 24 near the position where the seated person naturally lowers his / her arm away from the main frame 2.

  The arc guide portion 19 is provided at the rear portion of the main frame 2 so as to face the inner sides of the outer walls 2b and 2b. The arc guide portion 19 has an arc-shaped long hole 19 a that penetrates and supports the connecting shaft 29 that penetrates the center of the pin gear 20.

  The shape of the lower end surface of the long hole 19a is formed so as to coincide with the arc shape of the arc cross section 21b before the recess 21a of the fitting arc surface 21 of the main frame 2 is formed. Further, the arc guide portion 19 is arranged so that the arc cross section 21 b of the fitting arc surface 21 and the lower end surface of the long hole 19 a of the arc guide portion 19 coincide with the axial direction of the connecting shaft 29.

  The operation of the reaction force adjusting mechanism 1 of the locking mechanism 6 described above will be described below.

  First, when the valve in the cylinder 31a is opened by the operation of the operation mechanism 33 including the wire 36, the locking mechanism 6 is brought into a lockable state. The user can lean the backrest against the reaction force applied by the spring 9 and the gas spring 31 by leaning on the backrest, but if the load applied to the backrest is weakened or released, The backrest and the seat 7 are returned to the initial position by the reaction force of the spring 9 and the gas spring 31.

  The reaction force adjustment is normally performed at the initial position. However, when the handle 24 is gripped and the connecting shaft 29 is rotated, the pin gear 20 rotates while the pin 20b is fitted in the recess 21a of the fitting arcuate surface 21. As a result, the axis of the connecting shaft 29, that is, the connecting axis of the main frame 2 and the gas spring 31 moves. And the magnitude | size of the angle which the synchro flame | frame 4 and the gas spring 31 in an initial position changes by this connection shaft center moving. Since the arc guide portion 19 is an arc centered on the support shaft 38 at the initial position, the gas spring 31 does not expand and contract when the reaction force adjustment operation is performed at the initial position as described above. There is no need for an operating force to shorten the distance. In addition, when the user determines a desired reaction force, the user tries to lock from the initial position. From this point, the above-described configuration based on the assumption that the reaction force adjustment operation is performed at the initial position is preferable. is there.

  Here, the force that the gas spring 31 acts on the synchro frame 4 will be described in more detail. When viewed from the side, a support shaft 38 (with respect to the sync frame 4) that is the connection center between the sync frame 4 and the support frame 35 of the gas spring 31 from the axial center of the rotation shaft 3 that is the connection center between the sync frame 4 and the main frame 2 The direction toward the axial center of the gas spring 31) and the direction from the axial center of the coupling shaft 29, which is the coupling center of the gas spring 31 and the main frame 2, to the axial center of the support shaft 38 (extension of the gas spring 31). If the angle formed by the direction, that is, the direction of the force of the gas spring 31 itself is θ, the force (hereinafter referred to as effective reaction force) that causes the gas spring 31 to act in the direction to return the synchro frame 4 to the initial position is as follows. It is proportional to sin θ. Obviously, if θ is 0 ° or more and 90 ° or less, the effective reaction force increases as θ increases, and the change rate of the effective reaction force relative to θ increases as θ decreases.

  The idea of adjusting the reaction force by changing θ is the idea of the present invention, but the range in which θ is changed is not particularly limited. On the other hand, since the range of change in effective reaction force can be increased in the case of changing in the range close to 0 degrees compared to the case of changing in the range close to 90 degrees, for example, the backrest has tilted most backward. The value θ ′ of θ in the state is preferably 60 degrees or less, more preferably 45 degrees or less, and most preferably 30 degrees or less. In the present embodiment, the angle is changed in a range from about 5 degrees to about 30 degrees.

  As described above, by changing the angle between the sync frame 4 and the gas spring 31, the force acting in the direction of returning the sync frame 4 to the initial position changes, and the sync frame with respect to the main frame 2 is changed. The apparent magnitude of the reaction force of the gas spring 31 urging 4 is adjusted.

  The seated person adjusts the reaction force by operating the handle 24 while the backrest and the seat 7 are locked so that the reaction force is suitable for the user's preference and use condition.

  In addition, although the above-mentioned form is an example of the suitable form of this invention, it is not limited to this, A various deformation | transformation implementation is possible in the range which does not deviate from the summary of this invention. For example, in the present embodiment, in addition to the reaction force adjusting mechanism 1, a reaction force applying mechanism 5 that urges the synchro frame 4 toward the initial position is provided. Not a required configuration. That is, it is good also as a structure which does not have the reaction force provision mechanism 5, but is provided only with the reaction force adjustment mechanism 1. FIG.

  In the present embodiment, the locking mechanism 6 is configured so that the backrest and the seat 7 perform the locking operation in conjunction with each other. However, the present invention is applied to a locking mechanism in which only the backrest performs the locking operation. It is also possible to apply to a locking mechanism in which only the seat performs a locking operation.

  Furthermore, although this embodiment demonstrated the case where the reaction force adjustment mechanism 1 was applied to the locking mechanism of a chair, the reaction force adjustment method of this invention and the application object of a mechanism are not restricted to this, A support member is used. On the other hand, it can be applied as a mechanism for adjusting the reaction force with respect to the entire locking mechanism for swinging the supported member.

  In the present embodiment, the example in which the reaction force is adjusted by moving the coupling axis between the main frame 2 and the gas spring 31 has been described. However, the present invention is not limited to this, and the sync frame 4 and the gas spring are not limited thereto. It is also possible to adjust the reaction force by moving the connecting axis with 31.

It is sectional drawing which shows an example of embodiment of the reaction force adjustment mechanism for locking mechanisms which applied the reaction force adjustment method for locking mechanisms of this invention to the locking mechanism of a chair, and shows the state which has a to-be-supported member in an initial position. It is a top view of the reaction force adjustment mechanism for locking mechanisms of this embodiment, and shows the state where a supported member is in an initial position. It is a figure which shows the connection axial center moving means part of the reaction force adjustment mechanism for locking mechanisms of this embodiment. (A) is sectional drawing between the outer wall of a main frame, and a circular arc guide part. (B) is sectional drawing between a circular arc guide part and a gas spring. It is sectional drawing of the reaction force adjustment mechanism for locking mechanisms of this embodiment, and is a figure showing the change of the angle of the fluid spring by a connection shaft center moving. It is a side view which shows the chair provided with the conventional locking device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Reaction force adjustment mechanism 2 Support member 4 Supported member 29 Connecting shaft 31 Fluid spring 31a Cylinder

Claims (5)

  A support member and a supported member are pivotably connected, and a fluid spring is interposed between the support member and the supported member, and a connecting shaft center of the support member or the supported member and the fluid spring is provided. The reaction force of the fluid spring that urges the supported member toward the initial position relative to the support member by changing the angle formed by the supported member and the fluid spring at the initial position The reaction force adjusting method for a locking mechanism, wherein the size of the locking mechanism is adjusted.   A support member; a supported member that is swingably connected to the support member; a fluid spring having one end rotatably connected to the support member and the other end rotatably connected to the supported member; A locking mechanism reaction force adjusting mechanism comprising: a connecting shaft center moving means for moving a connecting shaft center between the supporting member or the supported member and the fluid spring.   The reaction force adjusting mechanism for a locking mechanism according to claim 2, wherein the fluid spring has a structure in which a piston is built in a cylinder, and spaces on both sides of the piston in the cylinder are communicated by a communication path. .   The connecting shaft center moving means is configured to place the connecting shaft center on an arc centering on a connection center on the side opposite to the connection shaft among the connection centers of the support member or the supported member and the fluid spring. The reaction force adjusting mechanism for a locking mechanism according to claim 2 or 3, wherein the mechanism is moved.   The supported member from the center of rotation of the supported member in the projection onto the plane orthogonal to the rotation axis of the supported member in a state where the supported member swings to the maximum extent from the initial position with respect to the supporting member. 5. The locking mechanism according to claim 2, wherein an angle formed by a direction of the fluid spring with respect to a point of action of the fluid spring and an extension direction of the fluid spring is 60 degrees or less. Reaction force adjustment mechanism.

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