JP2009084789A - Closing force assisting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a closing force assisting device which enables a door to be surely closed by increasing only a closing force in the closing of the door, without increasing an operating physical force when the opening of the door is started. <P>SOLUTION: This closing force assisting device comprises: a first cam 11 which is positively rotated between a door closer and a closing spring 23 by the opening operation of the door so as to store a spring force in the closing spring 23; a second cam 12 which undergoes the transmission of the spring force of the closing spring 23 by coming into contact with the closing spring 23 in the closing operation of the door via the center of the rotation of the first cam 11; a locking member 14 which locks the rotation of the second cam 12 by abutting on the second cam 12 in the closing operation of the door via the first cam 11; and a guide member 19 which guides the locking member 14 so that the locking member 14 can abut on the second cam 12 in the opening operation of the door, and which guides the locking member 14 so that the locking member 14 can be released from the state of abutting on the second cam 12 on completion of the closing operation of the door. In the closed state of the door, the closing force assisting device is set so that a gap can be provided between the first and second cams 11 and 12 and the closing spring 13. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a closing force assisting device that assists a closing force when closing a door and can reliably close the door.

  Conventionally, a door closer is used to automatically close the door. However, since the door closer has only a predetermined range of closing force, if the door does not move well or the door does not close completely due to a strong wind environment, it is necessary to replace the door closer with a large closing force. There is. When a door closer having a large closing force is used as described above, an operation force when opening the door is inevitably increased, and a large operation force is particularly required when opening the door.

Japanese Patent Application Laid-Open No. 2005-16128 describes an auxiliary device that reduces an operation force when opening a door. This auxiliary device is provided with a motor and its rotation shaft for a door closer including a piston that linearly reciprocates and a coil spring that presses the piston. The piston meshes with a pinion that rotates the hinge shaft of the door, and the piston reciprocates when the door opens and closes. The coil spring urges the piston to move in the door closing direction. The motor is driven so as to eliminate the urging force of the coil spring acting on the piston, whereby the operation force at the beginning of opening the door can be reduced.
Japanese Patent Laid-Open No. 2005-16128

  However, since the conventional auxiliary device uses a motor, it is necessary to operate a motor switch before operating the door knob, which is a complicated operation. Also, it has the problem of not working at the time of power failure

  The present invention has been made in consideration of such problems, and without increasing the operating force at the beginning of opening when opening the door, only the closing force at the time of closing the door is increased. An object of the present invention is to provide a closing force assisting device and a door closer that can be reliably closed.

  The closing force assisting device according to the first aspect of the invention is a device for assisting the closing force of the door by the spring force of the closing spring during the closing operation of the door, and forward and reverse rotation between the door and the closing spring. A first cam that rotates forward by a door opening operation and stores a spring force in the closing spring; and a rotation center of the first cam that can rotate forward and backward. A second cam to which the closing spring contacts and the spring force of the closing spring is transmitted during operation is provided to be swingable to the first cam. When the door is closed, the second cam is abutted against the second cam. A lock member that contacts and locks the rotation of the second cam, and guides the lock member to abut against the second cam when the door is opened, while the lock member is closed when the door is closed. A guide member that guides the second cam so as to disengage from the contact with the second cam The provided, in the closed state of the door, characterized in that it is configured so as to have a gap between the spring closing the first and second cams.

  The invention according to claim 2 is the closing force assisting device according to claim 1, wherein the first cam includes a contact portion having a constant radius from a rotation center and contacting the closing spring, and the closing spring Is characterized in that a spring force is transmitted to the first cam from a position eccentric from the rotation center.

  The invention according to claim 3 is the closing force assisting device according to claim 1 or 2, wherein the second cam, the lock member, and the guide member are urged in the same direction as the forward rotation direction of the first cam. It is characterized by being.

  A fourth aspect of the present invention is the closing force assisting device according to any one of the first to third aspects, wherein the closing spring moves in the direction of the spring force and contacts the first cam and the second cam. And a detachable slider.

  Invention of Claim 5 is the closing force auxiliary | assistance apparatus of any one of Claims 1-4, Comprising: The said 2nd cam has a contact surface with which the said locking member contact | abuts, The contact surface is inclined toward the rocking locus side of the lock member.

  In the present invention, the first cam stores a spring force in the closing spring when the door is opened. The stored spring force is transmitted to the first cam via the second cam and the lock member during the door closing operation, and is transmitted from the first cam to the door. Therefore, the closing force when closing the door is increased, and the door can be reliably closed. Further, in the closed state of the door, a gap is formed between the first cam and the second cam and the closing spring, so that the force of the closing spring does not act on these cams and the door is opened. There is no need to increase the operating force at the beginning of opening.

  Hereinafter, the present invention will be described in detail with reference to the illustrated embodiments. In each embodiment, the same member is assigned the same reference numeral.

(First embodiment)
FIGS. 1-6 shows the structure of the closing force assistance apparatus in 1st Embodiment of this invention, FIGS. 7-11 shows the action | operation.

  The closing force assisting device 1 is attached to a door closer 2 as shown in FIGS. 1 and 2. The door closer 2 has a box-like closer body 2a for storing mechanical parts, and the closer body is attached to a building wall (not shown) via an arm portion 2b. A main shaft 3 protrudes from the closer body 2a, and a connecting shaft portion 51a of the first cam 11 described later is fitted to the main shaft 3. The connecting shaft portion 51a of the first cam 11 is a square shaft, and is connected to the main shaft 3 formed in the same shape via the joint member 9 so that the first cam 11 rotates with the main shaft 3. Are communicated to each other.

  As shown in FIGS. 3 to 6, the closing force assisting device 1 includes a first cam 11, a second cam 12, a lock member 14, a guide member 19, and a closing spring 23 in a space formed by the bases 17 and 18. Contained and configured.

  As shown in FIG. 6, the first cam 11 is integrally provided with a shaft body 51 that penetrates in the vertical direction. From the one end side (lower end side) to the other end side (upper end side), the shaft body 51 has the above-described rectangular connection shaft portion 51a, columnar first shaft portion 51b, columnar second shaft portion 51c, It is comprised from the square-shaped connection shaft part 51d. Then, the first cam portion 51b is inserted into the support hole 17a of the base 17, and the second shaft portion 51c is inserted into the support hole 18a of the base 18, so that the first cam 11 is directed to the bases 17 and 18 in the forward and reverse directions. Is rotatably supported.

  The first cam 11 rotates around the shaft body 51 as a rotation center. The first cam 11 has a shape in which a part of a circle is cut out, and a contact portion 11f is formed on an end surface of the cutout portion. The contact portion 11f comes into contact with a convex portion 22b of a slider 22 provided on a closing spring 23 described later. The slider 22 comes into contact with the contact portion 11f at a position eccentric from the rotation center (shaft body 51) of the first cam 11.

  The second cam 12 has a shaft hole 12a. When the second shaft portion 51c of the first cam 11 passes through the shaft hole 12a, the second cam 12 is attached to the first cam 11 so as to be rotatable forward and backward. It is done. Therefore, the shaft 51 is the center of rotation of the second cam 12 and is the same center of rotation as the first cam 11. A slot 12b is formed in the second cam 12, and the convex pin 11c of the first cam 11 is inserted into the slot 12b. Therefore, the rotation range of the second cam 12 is a range in which the convex pin 11c slides in the long hole 12b.

  A torsion spring 13 is disposed between the first cam 11 and the second cam 12, and the hook 13a of the torsion spring 13 is inserted into the hook hole 11d of the first cam 11, and the hook 13b is the second cam. Twelve hook holes 12c are inserted. As a result, the second cam 12 is urged to rotate by the torsion spring 13. The urging direction is a direction in which the first cam 11 rotates in the forward direction, and is a counterclockwise direction in this embodiment.

  On the outer peripheral surface of the second cam 12, an arc-shaped cam portion 12h, an arc-shaped small diameter portion 12e having a smaller diameter than the cam portion 12h, and a recess 12f in which the small diameter portion 12e is further recessed are formed in order. . Further, the second cam 12 is formed with a contact portion 12d with which the slider 22 comes into contact. As shown in FIGS. 3 and 4, the contact portion 12 d is curved in an arc shape so as to be positioned closer to the slider 22 than the first cam 11. The convex part 22b of the slider 22 contacts the second cam 12, and the spring force of the closing spring 23 is transmitted by this contact.

  The lock member 14 has a hook shape, and one side thereof is rotatably attached to the first cam 11 by an attachment shaft 15. The lock member 14 rotates (swings) about the mounting shaft 15 so that the lock portion 14a on the other side comes into contact with the second cam. The lock member 14 is urged to rotate counterclockwise by a torsion spring 16.

  A cylindrical ring portion 18 b formed on the base 18 is inserted into the guide member 19 and is prevented from coming off by a retaining ring 20. Therefore, the guide member 19 is rotatably attached to the base 18. A torsion spring 21 is disposed between the guide member 19 and the base 18, and the guide member 19 is urged to rotate in the same direction (counterclockwise) as the urging direction of the second cam 12 by the torsion spring 21. Has been. A convex pin 19 a is formed on the guide member 19, and the convex pin 19 a is inserted into the long hole 18 c of the base 18. As a result, the guide member 19 is rotatable within the length range of the long hole 18c. Further, the guide member 19 is formed with a curved guide portion 19b. The guide portion 19b is formed to have a radius substantially equal to the small diameter portion 12e of the second cam 12.

  As shown in FIG. 3, the closing spring 23 is a compression spring and is inserted into a lateral hole 17 b formed in the base 17. A closing spring 23 is inserted into the slider 22, and the spring force of the closing spring 23 acts, so that the slider 22 moves in the direction of the first cam 11 and the second cam 12. The slider 22 is slidably inserted in the lateral hole 17b of the base 17. This sliding stops when the flange 22a on one end side comes into contact with the step 17d of the lateral hole 17b. A convex portion 22 b that protrudes in an arc shape is formed at the tip of the slider 22, and the convex portion 22 b faces the first cam 11 and the second cam 12. The lateral hole 17b of the base 17 is sealed with a lid 24.

  In the above structure, the relationship between the spring force of the closing spring 23, which is a compression spring, the torsion spring 21 that urges the guide member 19 to rotate, and the torsion spring 16 that urges the lock member 14 to rotate is Force> Spring force of torsion spring 21> Spring force of torsion spring 16 Further, the spring force of the torsion spring 13 that urges the second cam 12 to rotate is set to be smaller than the spring force of the closing spring 23. Furthermore, when the door is completely closed, the clearance L is set between the convex portion 22b of the slider 22 and the second cam 12 (see FIG. 7).

  Next, the operation in this embodiment will be described with reference to FIGS.

  FIG. 7 shows a state in which the door is completely closed. The slider 22 is stopped by the flange portion 22a coming into contact with the stepped portion 17b of the base 17, and the contact portion between the convex portion 22b of the slider 22 and the second cam 12 is shown. A gap L is formed between 12d. Since the second cam 12 is urged to rotate counterclockwise by the torsion spring 13, the rotation is stopped when the elongated hole 12 b hits the convex pin 11 c of the first cam 11. Since the guide member 19 is urged to rotate counterclockwise by the torsion spring 21, the convex pin 19 a comes into contact with the elongated hole 18 c of the base 18 and stops.

  When the door is opened in the state of FIG. 7, the first cam 11 rotates counterclockwise in synchronization with the main shaft 3 of the door closer 2. Along with this, the second cam 12 also rotates counterclockwise in synchronization with the first cam 11, but when the contact portion 12 d comes into contact with the convex portion 22 b of the slider 22, the rotation stops. This is because the spring force of the closing spring 23 is larger than that of the torsion spring 13. At this time, since the guide member 19 is not related to the movement of the cams 11 and 12, it is in a stopped state.

  When the first cam 11 rotates counterclockwise, the lock member 14 also rotates counterclockwise. For this reason, the lock portion 14 a of the lock member 14 is transferred from the guide portion 19 b of the guide member 19 to the small diameter portion 12 e of the second cam 12. At this time, since the guide portion 19b and the small diameter portion 12e have substantially the same diameter, the lock portion 14a of the lock member 14 can move smoothly. Since the range in which only the first cam 11 rotates in the above is only twisting the torsion spring 13, it can be moved with a very small force. By matching this range with a range that requires a very large force at the beginning of opening the door, which is a characteristic of the door closer, the operating force for opening the door will change even if the closing force assisting device 1 is attached to the door closer 2. There is no.

  FIG. 8 shows a state where a range in which a very large force is required at the start of opening the door is passed. In this state, for example, the door is opened about 15 °. When the door is opened so far, the contact portion 11 f of the first cam 11 also hits the convex portion 22 b of the slider 22. Accordingly, the first cam 11 is rotated by the opening operation of the door, and the closing spring 23 is compressed. Due to this compression, the closing spring 23 stores a spring force that assists the closing force of the door. This range is a range in which a very large force at the beginning of opening the door is required and the door can be opened with a small force. Therefore, even if a force for compressing the closing spring 23 is applied. The door can be opened lightly.

  FIG. 9 shows a state where the door is further opened to allow people to enter and exit. In this state, for example, the door is opened about 45 °. Both the first cam 11 and the second cam 12 rotate counterclockwise, and the contact position with the convex portion 22b of the slider 22 has a constant radius from the contact portions 11f and 12d of the first cam 11 and the second cam 12. Move to the cam surface you have. The radius on the cam surface is set so that the first cam 11 has a radius R1 and the second cam 12 has a radius R2, and the radius R1 is slightly larger than the radius R2. Accordingly, only the first cam 11 is in contact with the convex portion 22 b of the slider 22 at this position.

  Since the second cam 12 is always urged to rotate counterclockwise by the torsion spring 13, when the contact with the convex portion 22b of the slider 22 is lost, the other end of the elongated hole 12b of the second cam 12 is the first end. The cam 11 rotates counterclockwise until it hits the convex pin 11c of the cam 11, and the second cam 12 stops rotating due to contact with the convex pin 11c. When only the second cam 12 rotates counterclockwise, the recess 12 f of the second cam 12 moves to a position facing the lock portion 14 a of the lock member 14. Since the lock member 14 is urged to rotate counterclockwise by the torsion spring 16, the lock member 14 rotates counterclockwise. As a result, the lock portion 14 a of the lock member 14 falls from the small diameter portion 12 e of the second cam 12 into the recess 12 f. Due to this depression, the lock portion 14 a of the lock member 14 comes into contact with the contact surface 12 g of the second cam 12.

  In the first cam 11, the radius R1 of the cam surface is a constant radius from the center of rotation (shaft body 51). Therefore, even if the first cam 11 further rotates (that is, the door is opened) The closing spring 23 is not compressed. For this reason, the operating force for opening the door does not increase.

  FIG. 10 shows a state in which the door opened as described above is closed by the force of the door closer 2. In this state, the closing force assisting device 1 starts assisting the closing force.

  When the door is closed, the first cam 11 and the second cam 12 rotate in the clockwise direction. FIG. 10 shows a state in which the door has an opening angle of 30 °. When the door is closed to this angle, the spring force of the closing spring 23 acts on the second cam 12 through the convex portion 22b of the slider 22, and This is the force that rotates the two cams 12 in the clockwise direction. However, since the clockwise rotation of the second cam 12 is locked by the lock member 14, this force is transmitted from the contact surface 12 g of the second cam 12 to the lock portion 14 a of the lock member 14 and further to the first cam 11. Is done. Accordingly, this force rotates the main shaft 3 of the door closer 2 in the direction in which the door is closed, and the closing force of the door of the door closer 2 can be increased.

  When the door is further closed from the state of FIG. 10, the lock portion 14 a of the lock member 14 comes into contact with the guide portion 19 b of the guide member 19. The guide member 19 is urged to rotate counterclockwise by the torsion spring 21, but the lock member 14 is strongly transmitted clockwise by the second cam 12, and therefore the lock member 14 is guided by the guide member 19. Rotate clockwise.

  FIG. 11 shows a state in which the closing force assisting by the closing force assisting device 1 has been completed, for example, a state immediately before the door whose door has an opening angle of 2 ° is completely closed.

  In this state, the flange portion 22 a of the slider 22 hits the stepped portion 17 d of the base 17, and the projecting portion 22 b of the slider 22 is in contact with the contact portion 12 d of the second cam 12. The guide member 19 is further rotated clockwise by the lock member 14.

  When the door is slightly closed from the state of FIG. 11, the first cam 11 and the second cam 12 rotate in the clockwise direction, and therefore, between the convex portion 22 b of the slider 22 and the contact portion 12 d of the second cam 12, A slight gap L is generated (see FIG. 7). When the gap L is generated, the spring force of the closing spring 23 that has acted on the second cam 12 is lost, and no large force acts on the lock member 14. At this time, since the spring force of the torsion spring 16 is smaller than the spring force of the torsion spring 21, the guide member 19 rotates counterclockwise by the force of the torsion spring 21 and returns to the state of FIG. In this case, the gap L may be such that the spring force of the closing spring 23 does not act on the second cam 12 and is negligible, and does not hinder the assist of the closing force.

  In such an embodiment, the closing force when closing the door is increased by the spring force of the closing spring 23 stored in the first cam 11, and the door can be reliably closed. In the fully closed state of the door, a gap is formed between the first cam 11 and the second cam 12 and the closing spring 23, so that the spring force of the closing spring 23 does not act on the first cam. There is no need to increase the operating force at the beginning of opening the door.

  In this embodiment, even when the door is partially opened and closed, the next opening and closing is normally performed without malfunction. For example, even if the door is closed and the door is closed and the door is closed as it is, the closing force (spring force) is accumulated in the closing spring 23 if the door is opened to the extent that the next person enters and exits. Operates normally. Further, it is not necessary to open the door to the fully open position for the closing spring 23 to accumulate the closing force, and the closing force is accumulated if the door is opened to the extent that a person enters and exits. Furthermore, since the spring force of the closing spring 23 is not working near the fully open door, no force acts on the main shaft of the door closer. For this reason, there is no influence on the door stop function in the fully open position of the door closer. The door stop function is a function for stopping the opening of the door when the door is opened about 90 °.

(Second Embodiment)
FIG. 12 shows a second embodiment of the present invention. In the figure, the chain line indicates the swing locus of the lock portion 14 a at the tip of the lock member 14. In this embodiment, the contact surface 12g of the second cam 12 is greatly inclined toward the swing locus side of the lock member 14. By tilting in this way, when the second cam 12 rotates counterclockwise and is locked by the lock portion 14a of the lock member 14, the lock portion 14a of the lock member 14 is brought into contact with the contact surface 12g of the second cam 12. You can always touch. Thereby, at the moment when the spring force (closing assisting force) of the closing spring 23 acts on the second cam 12, the sound generated by the contact surface 12g of the second cam 12 contacting the locking portion 14a of the locking member 14 is generated. Can be prevented.

(Third embodiment)
FIG. 13 shows a third embodiment of the present invention. In this embodiment, a viscous fluid 25 such as viscous grease is sealed between the ring portion 18 b of the base 18 and the guide member 19. The viscous particles 25 are sealed by a seal 28. Thereby, since the guide member 19 rotates at a slow speed, it is possible to prevent generation of sound when the convex pin 19a hits the elongated hole 18c of the base 18.

(Fourth embodiment)
FIG. 14 shows a fourth embodiment of the present invention. In this embodiment, a shaft portion 22d extending in the axial direction is formed inside the slider 22, and a screw portion 22c is formed inside the shaft portion 22d. Further, a bolt 26 is passed through the lid 24, and the bolt 26 is screwed into the threaded portion 22 c of the slider 22. The outer shape of the slider 22 is preferably non-circular.

  In this structure, the size of the gap L between the convex portion 22b of the slider 22 and the contact portion 12d of the second cam 12 can be adjusted by adjusting the bolt 26 and the screw portion 22c. For this reason, when attaching the closing force assisting device 1 to the door closer 2, even if the gap L changes depending on the rotational position of the main shaft 3 of the door closer 2, the bolt 26 can be rotated to adjust the gap L to a certain amount. Further, the gap L can be made as small as possible, and a closing assisting force in the closing operation of the door can be exhibited.

(Fifth embodiment)
FIG. 15 shows a fifth embodiment of the present invention. In this embodiment, a roller 27 is rotatably attached to the convex portion 22 b of the slider 22. Therefore, since the frictional force at the time of contact between the first cam 11 and the second cam 12 and the slider 22 is reduced, there is an advantage that durability is improved.

(Sixth embodiment)
FIG. 16 shows a sixth embodiment of the present invention. In this embodiment, the first cam 11 has a structure in which a pair is provided across the second cam 12. That is, the first cam 11 is arranged so as to sandwich the second cam 12. By disposing the pair of first cams 11 in this way, a biased load is not applied regardless of which cam the convex portion 22b of the slider 22 contacts, and stable operation is possible.

  In this embodiment, the first cam 11 is separate from the shaft body 51, and the first cam 11 is fixed to the shaft body 51 by fitting the shaft body 51. 51e is a fitting part of the first cam 11 in the shaft body 51, and the outer shape is formed in a non-circular shape, whereby the first cam 11 can rotate integrally with the shaft body 51.

(Seventh embodiment)
FIG. 17 shows a seventh embodiment of the present invention. In this embodiment, the first to sixth embodiments described above are incorporated into the door closer 31. The door closer 31 includes a box-like closer main body 2a attached to the door and a main shaft 3 penetrating the closer main body 2a in the thickness direction, and the main shaft 3 is connected to the door via the arm portion 2b. Therefore, when the door is opened and closed, the main shaft 3 rotates in the forward and reverse directions.

  A cylinder 32 is formed inside the closer body 2a, and a piston 33 is disposed inside the cylinder 32 so as to be capable of reciprocating. The piston 33 is engaged with the main shaft 3, and the main shaft 3 rotates in the forward and reverse directions when the piston 33 reciprocates. A coil spring 34 that presses the piston 33 is provided inside the cylinder 32. The coil spring 34 urges the piston 33 to urge the main shaft 3 to rotate in the door closing direction via the piston 33, thereby applying a closing force to the door.

  In this embodiment, the first cam 11 is formed integrally with the main shaft 3 and rotates forward and backward with the main shaft 3 as the door is opened and closed. A second cam 12 is attached to the first cam 11 so as to rotate forward and backward. A closing spring 23 abuts on the second cam 12 via a slider 22, and the spring force of the closing spring 23 is transmitted. A lock member 14 that abuts against the second cam 12 and locks the rotation of the second cam 12 is attached to the first cam 11 so as to be swingable. While the lock member 14 is guided so as to come into contact with the second cam 12, the lock member 14 is provided with a guide member 19 that is released from contact with the second cam 12 when the door closing operation is finished. The structure described in Examples 1 to 6 is used for the above structure.

  Thus, by incorporating a mechanism for assisting the opening and closing force into the closer body 2a, the door closing force is very strong, and when opening the door, the door closer 31 can be operated efficiently with an extremely small force. .

It is a front view which shows the state which attached the closing force assistance apparatus in Example 1 to the door closer. It is a side view of a closing force auxiliary device. It is the sectional view on the AA line in FIG. It is the BB sectional view taken on the line in FIG. It is CC sectional view taken on the line in FIG. It is a disassembled perspective view which shows main structures. It is a side view which shows the main structures of the state in which the door is closed completely. It is a side view which shows the main structures of the state which started door opening. It is a side view which shows the main structures of the state which opened the door to the angle which a person can go in and out. It is a side view which shows the main structures of the state which started the closing operation of a door. It is a side view which shows the main structures of a state just before a door closes completely. It is a side view which shows the main structures of 2nd Embodiment. It is sectional drawing which shows the main structures of 3rd Embodiment. It is sectional drawing of 4th Embodiment. It is sectional drawing of 5th Embodiment. It is sectional drawing of 6th Embodiment. It is sectional drawing of 7th Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Closing force assisting device 2, 31 Door closer 2a Closer body 3 Main shaft 11 First cam 11f Contact portion 12 Second cam 12d Contact portion 12e Small diameter portion 12g Contact surface 13 Torsion spring 14 Lock member 14a Lock portion 16 Torsion springs 17, 18 Base 19 Guide member 21 Torsion spring 22 Slider 23 Closing spring 32 Cylinder 33 Piston 34 Coil spring 51 Shaft

Claims (5)

A device that assists the closing force of the door closer by the spring force of the closing spring when the door is closed.
A first cam that is disposed between the door closer and the closing spring so as to be able to rotate in the forward and reverse directions, and that rotates forward by an opening operation of the door and stores a spring force in the closing spring;
A second cam provided at the rotation center of the first cam so as to be able to rotate in the forward and reverse directions, and when the door is closed, the closing spring contacts and the spring force of the closing spring is transmitted;
A locking member provided on the first cam so as to be swingable, and locking the rotation of the second cam in contact with the second cam when the door is closed;
When the door opening operation is performed, the lock member is guided so as to contact the second cam, and when the door closing operation is completed, the lock member is guided so as to be detached from the contact with the second cam. A guide member,
The closing force assisting device is set to have a gap between the first cam and the second cam and the closing spring in the closed state of the door.   The first cam and the second cam have a contact portion having a constant radius from a rotation center and contacting the closing spring, and the closing spring applies a spring force from a position eccentric from the rotation center. 2. The closing force assisting device according to claim 1, wherein the closing force assisting device transmits to two cams.   2. The second cam and the guide member are urged in the same direction as the positive rotation direction of the first cam, and the lock member is urged toward the rotation center of the second cam. Or the closing force assistance apparatus of 2 description.   The closing force assist according to any one of claims 1 to 3, wherein the closing spring includes a slider that moves in the direction of the spring force and contacts and separates from the first cam and the second cam. apparatus.   The said 2nd cam has a contact surface with which the said lock member contacts, The said contact surface inclines toward the rocking locus side of the said lock member, The 1st characterized by the above-mentioned. 5. The closing force assisting device according to any one of 4 above.

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