Door closer

Abstract

To improve workability when changing a stop angle.SOLUTION: The door closer comprises: a bracket 1; a stop member 32; a link 2 that rotates around an axis line 3 relative to the bracket 1 and the stop member 32 in accordance with an opening / closing action of a door; a stop mechanism that holds the door at a stop angle by stopping a rotation of the link 2 relative to the stop member 32 when the door is at the stop angle; an operation member 7 operated by an operator in a first direction and a second direction, which holds the stop member 32 at an engagement position when operated in the first direction and enables the stop member 32 to be moved from the engagement position to an engagement release position when operated in the second direction; and an auxiliary tool 4 that receives a force from the operation member 7 when the operation member 7 is operated in the second direction, and applies the received force to the stop member 32 to move the stop member 32 to the engagement release position side.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a door closer equipped with a stop mechanism that holds a door open. [Background technology]

[0002] The door closer described in Patent Document 1 below is equipped with a stop mechanism for holding the door at a predetermined opening angle, i.e., the stop angle. To change the stop angle, the plate cam is lowered from the engagement position to the disengagement position, rotated relative to the serration shaft, and then raised back to the engagement position. When the plate cam descends from the engagement position to the disengagement position, it falls naturally under its own weight. However, frictional forces in various parts may prevent the plate cam from falling under its own weight. Therefore, an operator must manually lower the plate cam.

[0003] Furthermore, the door closer described in Patent Document 2 below is equipped with a spring that biases an upper bush having serrations toward the disengagement position. When the stop angle is changed, the upper bush is prone to falling due to the biasing force of the spring. However, even if the biasing force of the spring is acting on the upper bush, it is not guaranteed that the upper bush will fall when the stop angle is changed, which would still require more work for the worker. Furthermore, when raising the upper bush from the disengagement position to the engagement position, the upper bush must be raised against the biasing force of the spring, which reduces workability. Using a strong spring to ensure the upper bush falls further reduces workability when raising the upper bush to the engagement position. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 3811360 [Patent Document 2] Patent No. 3564113

Summary of the Invention

Problems to be Solved by the Invention

[0005] An object of the present invention is to improve workability when changing the stop angle.

Means for Solving the Problems

[0006] The door closer according to the present invention includes a bracket provided with a first serration around a predetermined axis, a second serration meshing with the first serration, the second serration being movable along the axis between a meshing position where the second serration meshes with the first serration and a disengaged position where the second serration is separated from the first serration, and when in the meshing position, rotation with respect to the bracket becomes impossible and the door can be held at the stop angle, and when in the disengaged position, rotation with respect to the bracket becomes possible and the stop angle can be adjusted, a stop member, a link that rotates around the axis with respect to the bracket and the stop member in the meshing position as the door opens and closes, a stop mechanism that holds the door at the stop angle by stopping the rotation of the link with respect to the stop member in the meshing position when the door reaches the stop angle, an operation member that is operated by an operator in a first direction and a second direction, holds the stop member in the meshing position when operated in the first direction, and makes the stop member movable from the meshing position to the disengaged position when operated in the second direction, and an auxiliary tool that receives a force from the operation member when the operation member is operated in the second direction and acts the received force on the stop member to move the stop member toward the disengaged position side.

[0007] According to this configuration, when changing the stop angle, the operator operates the operating member in the second direction. When the operating member is operated in the second direction, the stop member can move from the engaged position toward the disengaged position. Then, when the operating member is operated in the second direction, the auxiliary tool receives a force from the operating member. The auxiliary tool applies the force received from the operating member to the stop member, causing the stop member to move toward the disengaged position. Since the auxiliary tool moves the stop member toward the engaged position in this way, the operator only needs to operate the operating member in the second direction, eliminating the need for a separate operation to move the stop member toward the disengaged position.

[0008] In particular, it is preferable that the auxiliary tool includes a pressure-receiving piece that receives a force from the operating member, an acting piece that abuts against at least one of the stop member and the link and applies a force to move the stop member toward the disengaged position directly or via the link, and a connecting piece that connects the pressure-receiving piece and the acting piece. According to this configuration, when the operating member is operated in the second direction, a force acts from the operating member on the pressure-receiving piece of the auxiliary tool. The force received by the pressure-receiving piece from the auxiliary tool is transmitted to the acting piece via the connecting piece. Since the acting piece is in contact with the stop member or the link, the force transmitted to the acting piece acts directly on the stop member or acts on the stop member via the link. The stop member moves to the disengaged position due to the force from the acting piece.

[0009] Furthermore, the operating member is a bolt, and the pressure-receiving piece is provided with an operation hole for operating the head of the bolt. When the bolt is operated in the second direction, it is preferable that the head of the bolt presses against the peripheral portion of the operation hole. According to this configuration, since the pressure-receiving piece is provided with the operation hole, the head of the bolt can be easily operated by a tool via the pressure-receiving piece. Then, when the bolt is operated in the second direction, the head of the bolt presses against the peripheral portion of the operation hole in the pressure-receiving piece, so that a force surely acts from the bolt on the pressure-receiving piece.

[0010] Further, it is preferable that a receiving recess for engaging the head of the bolt is provided in the peripheral portion of the operation hole. According to this configuration, when the bolt is operated in the second direction, the head of the bolt engages with the receiving recess of the pressure receiving piece, so that the force from the bolt acts on the pressure receiving piece reliably.

Effects of the Invention

[0011] As described above, when changing the stop angle, the auxiliary tool is moved to the disengaged position of the stop member by receiving the force from the operation member, so that the workability when changing the stop angle is improved and the work burden on the operator is reduced.

Brief Description of the Drawings

[0012]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Embodiments for Carrying Out the Invention

[0013] Hereinafter, a door closer according to an embodiment of the present invention will be described with reference to the drawings. The door closer in this embodiment includes a door closer body (not shown) attached to one of a door and a door frame, a bracket 1 attached to the other of the door and the door frame, a link mechanism that connects the door closer body and the bracket 1, and an auxiliary tool 4 that is detachably attached when adjusting the stop angle. In this embodiment, a case where the door closer body is attached to the door and the bracket 1 is attached to the door frame will be described. The link mechanism includes a first link (not shown) and a second link 2 (link). One end of the first link is connected to the main shaft of the door closer body, and the first link rotates together with the main shaft about the main shaft. One end of the second link 2 is rotatably connected to the other end of the first link. Then, as shown in FIG. 1, the bracket 1 is rotatably connected to the other end of the second link 2. The door rotates, for example, about an axis in the vertical direction. The main shaft has an axis in the vertical direction. The rotation axis between the first link and the second link 2 is along the vertical direction, and the rotation axis between the second link 2 and the bracket 1 is also along the vertical direction. This rotation axis between the second link 2 and the bracket 1 will be referred to as the bracket axis 3. The bracket 1 is screwed, for example, from below into the fitting hole of the building hardware on the upper frame of the door frame.

[0014] Figures 1 and 2 show the state where the door closer is installed and the door can be held at the stop angle, and Figure 3 shows the state during the operation of adjusting the stop angle. The serration shaft 5 extends downward from the bracket 1. The serration shaft 5 is fixed to the bracket 1 by caulking. The serration shaft 5 is located on the bracket axis 3. The serration shaft 5 is cylindrical, and an internal thread portion 6 is formed at the lower part of its inner peripheral surface, and a bolt 7 is screwed into the internal thread portion 6. The bolt 7 is located on the bracket axis 3. The bolt 7 has a head 8 and a shaft portion 9, and the head 8 is located on the lower side. That is, the bolt 7 is screwed into the serration shaft 5 from the lower side. When the bolt 7 is rotated in the tightening direction which is the first direction, the bolt 7 rises, and when the bolt 7 is rotated in the loosening direction which is the second direction, the bolt 7 descends.

[0015] A first serration 10 is formed on the outer peripheral surface of the serration shaft 5. The first serration 10 is a vertical serration extending in the vertical direction, and is formed over the entire circumference of the serration shaft 5 centered on the bracket axis 3. The first serration 10 is formed in the central part of the entire length of the serration shaft 5, and the first serration 10 is not formed in the upper and lower parts of the outer peripheral surface of the serration shaft 5. The upper part of the outer peripheral surface of the serration shaft 5 is an upper support surface 11, which is adjacent to the upper side of the first serration 10. The lower part of the outer peripheral surface of the serration shaft 5 is a lower support surface 12, which is adjacent to the lower side of the first serration 10. The lower support surface 12 has a smaller diameter than the upper support surface 11.

[0016] The other end of the second link 2 branches vertically and has a pair of plate-like branched pieces facing each other vertically. The upper branched piece 20 and the lower branched piece 21, which are a pair of upper and lower branched pieces, are respectively rotatably supported by the serration shaft 5. The upper branched piece 20 is supported by the upper support surface 11 of the serration shaft 5 via a cylindrical upper bush 30, and the lower branched piece 21 is supported by the lower support surface 12 of the serration shaft 5 via a cylindrical lower bush 31. A lower flange 31a is formed at the lower end of the lower bush 31.

[0017] A slit 22 extending in the horizontal direction is formed between the upper branch piece 20 and the lower branch piece 21. A plate-shaped stop member 32 is disposed in the slit 22. The serration shaft 5 penetrates the stop member 32 in the vertical direction. The stop member 32 is located above the lower bush 31. A through hole through which the serration shaft 5 is inserted is formed in the stop member 32, and a second serration 33 that meshes with the first serration 10 is formed on the wall surface of this through hole.

[0018] The stop member 32 is movable along the vertical direction with respect to the serration shaft 5. Specifically, it is movable between an engagement position where the second serration 33 meshes with the first serration 10 and a disengagement position where the second serration 33 disengages from the first serration 10. The states shown in FIGS. 1 and 2 are the states where the stop member 32 is located at the engagement position, and the state shown in FIG. 3 is the state where the stop member 32 is located at the disengagement position. When the stop member 32 is at the engagement position, the stop member 32 becomes non-rotatable with respect to the serration shaft 5. When the stop member 32 is at the disengagement position, the stop member 32 becomes rotatable about the bracket axis 3 with respect to the serration shaft 5.

[0019] The bolt 7 fastens the stop member 22 to the bracket 1. The states shown in FIGS. 1 and 2 are the states where the bolt 7 is tightened, and the stop member 32 has reached the upper end portion 10a of the first serration 10 and cannot rise further. The state shown in FIG. 3 is the state where the bolt 7 is loosened to a predetermined position, and the stop member 32 is separated downward from the serration shaft 5.

[0020] Also, the position where the stop member 32 reaches the upper end portion 10a of the first serration 10 is defined as the meshing position. Further, the disengaged position is defined as the position where the second serration 33 is completely separated downward from the first serration 10. Note that the stop member 32 can further descend from the state where the second serration 33 is separated downward from the first serration 10. Therefore, the disengaged position shown in FIG. 3 is an example.

[0021] FIG. 4 shows the stop member 32 in a single state. The stop member 32 is plate-shaped with the direction of the bracket axis 3 as the plate thickness direction. The peripheral portion of the upper surface of the stop member 32 is stepped down compared to the portion around the through-hole and is partially thin. The peripheral portion of the upper surface of the stop member 32 serves as the contact surface 34 against which the auxiliary tool 4 abuts. Also, on the upper surface of the stop member 32, an engaging cylinder portion 35 is formed around the through-hole and projects upward from the contact surface 34. By making the periphery of the engaging cylinder portion 35 one step lower and forming a thin portion, the gap between the upper branch piece 20 and the upper surface of the stop member 32 can be enlarged.

[0022] A cam surface 36 is formed on the peripheral surface of the stop member 32. The stop member 32 is a plate cam. As shown in FIGS. 2 and 3, a stop ball 37 abuts against the cam surface 36 of the stop member 32 from the outside. The stop ball 37 is built into the base end portions of the upper branch piece 20 and the lower branch piece 21 in the second link 2. Also, the second link 2 has a spring (not shown) that presses the stop ball 37 toward the stop member 32 built therein.

[0023] When the door rotates with the second serration 33 of the stop member 32 engaged with the first serration 10 of the serration shaft 5, the second link 2 rotates with respect to the serration shaft 5 as the door opens and closes, and the stop ball 37 rolls along the circumferential direction of the cam surface 36 while contacting the cam surface 36. An engagement recess 38 is formed at a predetermined position of the cam surface 36 as shown in FIG. 4. As the second link 2 rotates with respect to the serration shaft 5 and the stop member 32 as the door opens, the stop ball 37 rolls on the cam surface 36 and eventually engages with the engagement recess 38. FIG. 2 shows a state in which the stop ball 37 is engaged with the engagement recess 38. When the stop ball 37 engages with the engagement recess 38, the second link 2 can no longer rotate substantially with respect to the stop member 32. Therefore, the door stops at its opening angle and is held at that opening angle. The opening angle of the door when it is held open is referred to as the stop angle. The stop angle can be arbitrarily changed by setting the stop member 32 to the disengaged position. In the present embodiment, the engagement recess 38 of the stop member 32, the stop ball 37, and the spring constitute a stop mechanism for holding the door open.

[0024] The upper end surface of the above-described lower bush 31 is in contact with the lower surface of the stop member 32. In the state where the second serration 33 is engaged with the first serration 10 as shown in FIGS. 1 and 2, the lower bush 31 presses the stop member 32 upward, and the stop member 32 has reached the upper end portion 10a of the first serration 10 and is in a state where it cannot rise further. Therefore, the stop member 32 is sandwiched vertically between the lower bush 31 and the upper end portion 10a of the first serration 10.

[0025] A pressing plate 39 is disposed below the lower bush 31. The pressing plate 39 is disk-shaped, and its peripheral portion is in contact with the lower flange 31a of the lower bush 31. In the present embodiment, the lower bush 31 and the pressing plate 39 are configured as separate members, but they may be configured as a single member. A lower cover 40 is disposed below the pressing plate 39. The lower cover 40 covers substantially the entire lower surface of the pressing plate 39 from below.

[0026] The operating member in this embodiment is the bolt 7 described above. The head 8 of the bolt 7 is of the truss screw type, and the top surface 8a of the head 8 of the bolt 7 is dome-shaped or hemispherical. An engagement groove 8b for the tip of a driver as the tool 100 is formed at the center of the top surface 8a of the head 8 of the bolt 7. The engagement groove 8b is cross-shaped, and thus, a plus driver is used. The shaft portion 9 of the bolt 7 penetrates the pressing plate 39 and the lower cover 40 in the vertical direction and is screwed into the female screw portion 6 of the serration shaft 5. Incidentally, a spring washer 41 is disposed between the head 8 of the bolt 7 and the lower cover 40.

[0027] When changing and adjusting the stop angle in the door closer as described above, the auxiliary tool 4 is used. The auxiliary tool 4 is shown in Fig. 5. The auxiliary tool 4 is generally U-shaped and has a pressure receiving piece 50, an acting piece 51, and a connecting piece 52. The auxiliary tool 4 is preferably made of sheet metal. The pressure receiving piece 50 and the acting piece 51 face each other in the vertical direction. The pressure receiving piece 50 is located on the lower side, and the acting piece 51 is located on the upper side. The pressure receiving piece 50 and the acting piece 51 are parallel to each other. The connecting piece 52 connects the pressure receiving piece 50 and the acting piece 51 vertically. The pressure receiving piece 50 and the acting piece 51 extend from the connecting piece 52 in the horizontal direction and in a predetermined direction. The direction in which the pressure receiving piece 50 and the acting piece 51 extend from the connecting piece 52 is referred to as the extending direction. Also, the direction orthogonal to the extending direction in plan view is referred to as the width direction.

[0028] An operation hole 53 is provided in the pressure receiving piece 50. The operation hole 53 is located on the bracket axis 3. The operation hole 53 is a through hole that penetrates the pressure receiving piece 50. The operation hole 53 is formed to be large enough for the tip of the tool 100 to be inserted, and preferably, when the pressure receiving piece 50 is viewed from below, the head 8 of the bolt 7 located above the pressure receiving piece 50 can be visually recognized through the operation hole 53. Also, the operation hole 53 has a smaller diameter than the head 8 of the bolt 7, and the head 8 of the bolt 7 cannot pass through the operation hole 53.

[0029] In the upper part of the wall surface of the operation hole 53, a receiving recess 54 with which the top surface 8a of the head 8 of the bolt 7 can engage is formed. The receiving recess 54 is formed on the upper surface of the pressure receiving piece 50 and at the opening edge of the operation hole 53. The receiving recess 54 has, for example, a tapered shape that expands in diameter upward. The peripheral edge of the top surface 8a of the head 8 of the bolt 7 abuts against the receiving recess 54.

[0030] A notch 55 is formed in the acting piece 51. The notch 55 opens toward the side opposite to the connecting piece 52. The notch 55 is formed in a U shape so as to be notched from the tip end portion to the base end portion in the extending direction of the acting piece 51, that is, toward the connecting piece 52. The width W of the notch 55 corresponds to and is substantially the same as the outer diameter D of the engaging cylinder portion 35 of the stop member 32 described above. By forming the notch 55 in the acting piece 51, a pair of abutting arms 56 are formed on the acting piece 51. The pair of abutting arms 56 face each other in the width direction and are located on both sides of the notch 55. The abutting arm 56 extends toward the side opposite to the connecting piece 52 with the connecting piece 52 side as the base end portion and the side opposite to the connecting piece 52 as the tip end portion. That is, the abutting arm 56 extends along the extending direction. The abutting arm 56 extends beyond the position of the bracket axis 3 in the extending direction.

[0031] Fig. 6 shows the relationship between the auxiliary tool 4 and the stop member 32. The acting piece 51 of the auxiliary tool 4 is placed on the upper surface of the stop member 32. The acting piece 51 overlaps the upper side of the stop member 32, and the lower surface of the acting piece 51 abuts against the upper surface of the stop member 32. The pair of abutting arms 56 on the acting piece 51 abut against the abutting surface 34 of the stop member 32. Further, when the engaging cylinder portion 35 of the stop member 32 engages with the notch 55 of the acting piece 51 in the extending direction and the engaging cylinder portion 35 abuts against the innermost part of the notch 55, the acting piece 51 can no longer move to the right in the drawing in the extending direction. [[ID=X]] [[ID=Y]]

[0032] [[ID=Z]] Next, the operation procedure for changing the stop angle of the door closer attached to the door and the door frame will be described. First, prepare the auxiliary tool 4 as shown in FIG. 1, and attach the auxiliary tool 4 to the door closer as shown in FIG. 7. Specifically, insert the working piece 51 of the auxiliary tool 4 into the gap between the stop member 32 and the upper branch piece 20 from the tip side of the upper branch piece 20 and the lower branch piece 21. Insert the working piece 51 from the tip side of the second link 2 toward the stop ball 37, and place the working piece 51 on the stop member 32. More specifically, engage the engaging cylinder portion 35 of the stop member 32 with the notch portion 55 of the working piece 51, and place the pair of abutting arm portions 56 of the working piece 51 on the abutting surface 34 of the stop member 32. Push the working piece 51 until the engaging cylinder portion 35 of the stop member 32 reaches the innermost part of the notch portion 55 of the working piece 51 and the working piece 51 of the auxiliary tool 4 can no longer move toward the stop ball 37. When the stop member 32 is in the meshing position as shown in FIGS. 1 and 2, the vertical gap T1 between the upper branch piece 20 and the abutting surface 34 of the stop member 32 is larger than the thickness T2 (vertical dimension) of the working piece 51.

[0033] In the state where the auxiliary tool 4 is attached to the door closer in the meshing state as shown in FIG. 7, the connecting piece 52 extends downward so as to bypass the radial outside of the stop member 32, the lower branch piece 21, the lower bush 31, the pressing plate 39, the lower cover 40, and the head 8 of the bolt 7. The connecting piece 52 is located radially outside the tip of the lower branch piece 21, and a predetermined gap exists between the tip of the lower branch piece 21 and the connecting piece 52. Further, the pressure receiving piece 50 is located below the head 8 of the bolt 7. The pressure receiving piece 50 is located at a predetermined distance below the head 8 of the bolt 7. Therefore, a gap exists between the upper surface of the pressure receiving piece 50 and the head 8 of the bolt 7. However, the upper surface of the pressure receiving piece 50 may be in contact with the head 8 of the bolt 7. Thus, the vertical interval T3 between the pressure receiving piece 50 and the working piece 51 in the auxiliary tool 4 is set to be equal to or greater than the vertical distance T4 between the upper surface of the stop member 32, which is the abutting surface 34 in this embodiment, and the top surface 8a of the head 8 of the bolt 7.

[0034] The operation hole 53 of the pressure-receiving piece 50 is located on the bracket axis 3 and is aligned with the head 8 of the bolt 7. That is, the operation hole 53 of the pressure-receiving piece 50 is located directly below the head 8 of the bolt 7. Therefore, when looking at the pressure-receiving piece 50 from below, the center of the top surface 8a of the head 8 of the bolt 7 can be visually recognized through the operation hole 53, and the engagement groove 8b for the tool 100 can be visually recognized. However, as will be described later, the operation hole 53 of the pressure-receiving piece 50 may be horizontally displaced with respect to the head 8 of the bolt 7.

[0035] After attaching the auxiliary tool 4 in this way, as shown in FIGS. 7 and 8(a), the tip of the tool 100 is inserted into the operation hole 53 and the tip of the tool 100 is engaged with the engagement groove 8b of the head 8 of the bolt 7. Then, the tool 100 is rotated in the direction of loosening the bolt 7 (the second direction). As the bolt 7 is loosened, the head 8 of the bolt 7 descends and approaches the pressure-receiving piece 50. Eventually, as shown in FIGS. 8(b) and 9, the top surface 8a of the head 8 of the bolt 7 abuts against the pressure-receiving piece 50 and engages with the receiving recess 54. Since the top surface 8a of the head 8 of the bolt 7 engages with the receiving recess 54 in this way, even if the operation hole 53 of the pressure-receiving piece 50 is horizontally displaced with respect to the head 8 of the bolt 7, the displacement will be corrected. Incidentally, as shown by the two-dot chain line in FIGS. 8(b) and 9, the lower cover 40 may descend together with the bolt 7 due to its own weight. Similarly, the pressing plate 39 may also descend together with the lower cover 40 due to its own weight.

[0036] Then, when the tool 100 is further rotated in the loosening direction from the state where the head 8 of the bolt 7 abuts against the pressure receiving piece 50 as shown in FIGS. 8(b) and 9, as the head 8 of the bolt 7 descends, the head 8 of the bolt 7 presses the pressure receiving piece 50 downward. That is, the pressure receiving piece 50 receives a downward force from the head 8 of the bolt 7. This force is transmitted to the acting piece 51 via the connecting piece 52 and becomes a force for pushing down the acting piece 51. Along with such further descending movement of the bolt 7, the acting piece 51 pushes down the stop member 32. When the downward force of the acting piece 51 acts on the stop member 32, as shown in FIG. 10, the stop member 32 descends from the meshing position to the disengaged position, and the second serration 33 moves away from the first serration 10 of the serration shaft 5 downward. Along with the descent of the stop member 32, the upper branch piece 20 and the lower branch piece 21 also move downward. Also, the lower bush 31 descends so as to be pushed by the stop member 32. Note that, as shown by the dashed two-dot line in FIG. 10, the lower cover 40 may descend together with the bolt 7 due to its own weight, and similarly, the pressing plate 39 may descend together with the lower cover 40 due to its own weight.

[0037] As described above, in the door closer according to the present embodiment, when changing the stop angle, by attaching the auxiliary tool 4, the auxiliary tool 4 pushes down the stop member 32 as the bolt 7 is loosened. Therefore, even when the stop member 32 does not fall due to its own weight, the stop member 32 can be surely descended, and the second serration 33 of the stop member 32 can be separated downward from the first serration 10 of the serration shaft 5. Accordingly, the stop member 32 can be surely descended to the disengaged position, and the stop angle can be adjusted smoothly. Further, since the operator only needs to perform the operation of loosening the bolt 7, the work load is reduced.

[0038] Also, regarding the attachment operation of the auxiliary tool 4, it only requires a simple attachment operation of inserting the working piece 51 between the upper branch piece 20 and the stop member 32. Furthermore, by inserting the working piece 51 of the auxiliary tool 4, the operation hole 53 of the pressure receiving piece 50 is automatically positioned directly below the bolt 7, so that the bolt 7 can be quickly loosened by the tool 100 through the operation hole 53. Moreover, when looking up at the pressure receiving piece 50 from below, the head 8 of the bolt 7 can be visually recognized through the operation hole 53, so that the tool 100 can be safely inserted into the operation hole 53 for work. Additionally, at the stage when the auxiliary tool 4 is attached, a gap is provided between the head 8 of the bolt 7 and the pressure receiving piece 50, so that when the bolt 7 is loosened, the self-weight of the auxiliary tool 4 also acts on the stop member 32. Moreover, the stop member 32 may start to free fall before the head 8 of the bolt 7 reaches the pressure receiving piece 50. When the stop member 32 starts to free fall in this way, the auxiliary tool 4 can be removed and the loosening operation of the bolt 7 can be continued.

[0039] In addition, in this embodiment, the receiving recess 54 was provided at the upper opening edge of the operation hole 53, but the receiving recess 54 may not be provided. The shape of the head 8 of the bolt 7 is also arbitrary, and the top surface 8a may not be spherical but flat. The bolt 7 may be configured to contact the flat upper surface of the pressure receiving piece 50 and push down the pressure receiving piece 50. The head 8 of the bolt 7 may have a shape with a flange.

[0040] Also, the contact surface 34 and the engaging cylinder portion 35 are provided on the upper surface of the stop member 32, but the contact surface 34 and the engaging cylinder portion 35 may not be provided, and the upper surface of the stop member 32 may be a flat surface.

[0041] In addition, in the above embodiment, the working piece 51 of the auxiliary tool 4 is configured to contact the upper surface of the stop member 32, but the working piece 51 may be configured to contact, for example, the upper surface of the lower branch piece 21 or the upper surface of the upper branch piece 20.

Explanation of Reference Numerals

[0042] 1 Bracket 2 Second Link 3 Bracket Axis 4 Auxiliary Tool 5 Serration Axis 6 Female Screw Portion 7 Bolt (Operating Member) 8 Head 8a Top Surface 8b Engagement Groove 9 Shaft Portion 10 First Serration 10a Upper End Portion 11 Upper Support Surface 12 Lower Support Surface 20 Upper Branch Piece 21 Lower Branch Piece 22 Slit 30 Upper Bush 31 Lower Bush 31a Lower Flange 32 Stop Member 33 Second Serration 34 Contact Surface 35 Engagement Cylinder Portion 36 Cam Surface 37 Stop Ball (Stop Mechanism) 38 Engagement Concave Portion (Stop Mechanism) 39 Pressing Plate 40 Lower Cover 41 Spring Washer 50 Pressure-Receiving Piece 51 Acting Piece 52 Connecting Piece 53 Operation Hole 54 Receiving Concave Portion 55 Notch 56 Contact Arm Portion 100 Tool

Claims

1. A bracket provided with a first serration around a predetermined axis, a second serration meshing with the first serration is provided, and the second serration is movable along the axis between a meshing position where the second serration meshes with the first serration and a disengaged position where the second serration is separated from the first serration. When in the meshing position, rotation with respect to the bracket becomes impossible and the door can be held at a stop angle. When in the disengaged position, rotation with respect to the bracket becomes possible and the stop angle can be adjusted. A stop member, a link that rotates around the axis with respect to the bracket and the stop member in the meshing position as the door opens and closes, a stop mechanism that holds the door at the stop angle by stopping the rotation of the link with respect to the stop member in the meshing position when the door reaches the stop angle, an operating member that is operated by an operator in a first direction and a second direction. When operated in the first direction, the stop member is held in the meshing position. When operated in the second direction, the stop member can be moved from the meshing position to the disengaged position, an auxiliary tool that receives a force from the operating member when the operating member is operated in the second direction and acts the received force on the stop member to move the stop member toward the disengaged position side, A door closer comprising the above.

2. The auxiliary tool has a pressure-receiving piece that receives a force from the operating member, an acting piece that abuts against at least one of the stop member and the link and directly or via the link acts a force toward the disengaged position on the stop member, and a connecting piece that connects the pressure-receiving piece and the acting piece. The door closer according to Claim 1.

3. The operating member is a bolt, and the pressure-receiving piece is provided with an operating hole for operating the head of the bolt. When the bolt is operated in the second direction, the head of the bolt presses the peripheral portion of the operating hole. The door closer according to Claim 2.

4. A receiving recess for engaging the head of the bolt is provided in the peripheral portion of the operating hole. The door closer according to Claim 3.

Images