Door closer

Abstract

To increase the degree of freedom in designing a cam in a door closer provided with the cam.SOLUTION: The cam includes a first transmission cam surface and a second transmission cam surface which are provided at positions different from each other in a first direction, and a first buffer cam surface and a second buffer cam surface which are provided at positions different from each other in the first direction; a transmission roller includes a first transmission follower 13b facing the first transmission cam surface and a second transmission follower 13a facing the second transmission cam surface; a buffer roller includes a first buffer follower 17a facing the first buffer cam surface and a second buffer follower 17b facing the second buffer cam surface; at a transmission switching angle, a state in which the first transmission cam surface is in contact with the first transmission follower 13b is switched to a state in which the second transmission cam surface is in contact with the second transmission follower 13a; and at a buffer switching angle, a state in which the first buffer cam surface is in contact with the first buffer follower 17a is switched to a state in which the second buffer cam surface is in contact with the second buffer follower 17b.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a door closer equipped with a cam. [Background technology]

[0002] In a door closer equipped with a cam, as in Patent Document 1 below, the cam elastically deforms a spring when the door opens. This type of cam-equipped configuration can generate a large closing force just before the door is fully closed. However, the closing force tends to be insufficient at relatively large opening angles. Furthermore, the cam moves a buffer piston when the door closes. Therefore, the amount of movement of the buffer piston is small, making it difficult to adjust the flow rate of hydraulic oil. This type of cam-equipped configuration places significant constraints on the design of the cam. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 5-20547 Summary of the Invention [Problem to be solved by the invention]

[0004] An object of the present invention is to increase the degree of freedom in designing a cam in a door closer equipped with a cam. [Means for solving the problem]

[0005] The door closer according to the present invention comprises a main shaft that rotates around an axis in a first direction in association with the opening and closing operation of the door, a cam that is provided on the main shaft and rotates together with the main shaft, a transmission roller that comes into contact with the cam, a slider that moves together with the transmission roller in a second direction perpendicular to the first direction in association with the rotation of the main shaft, and a closing spring that is elastically deformed by the slider when the door is opened and restored when the door is closed to apply a closing force to the main shaft via the slider, the cam having a first transmission cam surface and a second transmission cam surface that are provided at different positions from each other in the first direction, and the transmission roller facing the first transmission cam surface. The door has a first transmission follower that faces the first transmission follower and a second transmission follower that faces the second transmission cam surface, and from the closed door state to a predetermined transmission switching angle, the first transmission cam surface contacts the first transmission follower and the second transmission cam surface does not contact the second transmission follower, and at the transmission switching angle, the state changes from one in which the first transmission cam surface contacts the first transmission follower to one in which the second transmission cam surface contacts the second transmission follower, and at an opening angle greater than the transmission switching angle, the first transmission cam surface does not contact the first transmission follower and the second transmission cam surface contacts the second transmission follower.

[0006] With this configuration, the cam switches from the first transmission cam surface to the second transmission cam surface at the transmission switching angle. This allows for greater freedom in cam design compared to a single cam configuration, and allows for stronger closing force. In particular, the closing force can be strengthened at a relatively large opening angle.

[0007] In particular, it is preferable that the first transmission follower and the second transmission follower are provided coaxially with each other, and that the second transmission follower has a larger diameter than the first transmission follower. With this configuration, the transmission roller can be easily configured.

[0008] The door closer according to the present invention comprises a main shaft that rotates around an axis in a first direction in accordance with the opening and closing operation of the door, a cam that is provided on the main shaft and rotates together with the main shaft, a buffer roller that comes into contact with the cam, a buffer piston that moves together with the buffer roller in a second direction perpendicular to the first direction in accordance with the rotation of the main shaft to buffer the closing operation of the door, and a buffer spring that biases the buffer piston toward the main shaft, wherein the cam has a first buffer cam surface and a second buffer cam surface that are provided at different positions in the first direction, and the buffer roller has a first buffer follower that faces the first buffer cam surface and a second buffer follower that faces the second buffer follower. The door has a second buffer cam surface and an opposing second buffer follower, and from the closed door state up to a predetermined buffer switching angle, the first buffer cam surface contacts the first buffer follower and the second buffer cam surface does not contact the second buffer follower, and at the buffer switching angle, the state changes from one in which the first buffer cam surface contacts the first buffer follower to one in which the second buffer cam surface contacts the second buffer follower, and at an opening angle greater than the buffer switching angle, the first buffer cam surface does not contact the first buffer follower and the second buffer cam surface contacts the second buffer follower.

[0009] With this configuration, the cam switches from the first buffer cam surface to the second buffer cam surface at the buffer switching angle. This allows for greater freedom in cam design compared to a single cam configuration, making it easier to increase the amount of movement of the buffer piston. This makes it easier to control the door closing speed.

[0010] In particular, it is preferable that the first buffer follower and the second buffer follower are provided coaxially with each other, and the first buffer follower has a larger diameter than the second buffer follower. With this configuration, the buffer roller can be easily configured.

[0011] The door closer according to the present invention includes a main shaft that rotates around an axis in a first direction as the door opens and closes, a cam that is attached to the main shaft and rotates together with the main shaft, a transmission roller that comes into contact with the cam, a slider that moves together with the transmission roller in a second direction perpendicular to the first direction as the main shaft rotates, a closing spring that is elastically deformed by the slider when the door opens and returns to its original shape when the door closes, applying a closing force to the main shaft via the slider, a buffer roller that comes into contact with the cam, and a slider that moves together with the buffer roller in the second direction as the main shaft rotates. a buffer piston that moves to buffer the closing operation of the door, and a buffer spring that biases the buffer piston toward the main shaft, the cam has a first transmission cam surface and a second transmission cam surface that are provided at different positions in the first direction from each other, and a first buffer cam surface and a second buffer cam surface that are provided at different positions in the first direction from each other, the transmission roller has a first transmission follower that faces the first transmission cam surface and a second transmission follower that faces the second transmission cam surface, and from the closed door state to a predetermined transmission switching angle, the first transmission cam surface acts as the first transmission follower, At the transmission switching angle, the first transmission cam surface switches from contacting the first transmission follower to contacting the second transmission follower, and at an opening angle greater than the transmission switching angle, the first transmission cam surface does not contact the first transmission follower, and the second transmission cam surface contacts the second transmission follower. The buffer roller is connected to the first buffer follower facing the first buffer cam surface and the second buffer cam surface facing the second buffer cam surface. From the closed door state up to a predetermined buffer switching angle, the first buffer cam surface contacts the first buffer follower and the second buffer cam surface does not contact the second buffer follower, and at the buffer switching angle, the state changes from the first buffer cam surface contacting the first buffer follower to the second buffer cam surface contacting the second buffer follower, and at an opening angle greater than the buffer switching angle, the first buffer cam surface does not contact the first buffer follower and the second buffer cam surface contacts the second buffer follower.

[0012] With this configuration, the cam switches from the first transmission cam surface to the second transmission cam surface at the transmission switching angle. Also, the cam switches from the first buffer cam surface to the second buffer cam surface at the buffer switching angle. Therefore, compared to a single cam configuration, the degree of freedom in cam design is increased, the closing force can be increased, and the travel distance of the buffer piston can be easily increased.

[0013] In particular, it is preferable that the first transmitting cam surface and the second buffer cam surface are provided at different circumferential positions on the first peripheral surface of the cam, and the second transmitting cam surface and the first buffer cam surface are provided at different circumferential positions on the second peripheral surface of the cam. This configuration makes it easy to configure the cam. [Effects of the Invention]

[0014] As described above, the cam switches during the door opening operation, which increases the degree of freedom in cam design. [Brief explanation of the drawings]

[0015] [Figure 1] 3A and 3B show a door closer in a closed state according to an embodiment of the present invention, in which FIG. 3A is a plan view and FIG. 3B is a cross-sectional view taken along line AA of FIG. [Figure 2] FIG. [Figure 3] 4A and 4B are perspective views showing the main parts of the door closer. [Figure 4] FIG. [Figure 5] 4A and 4B are plan views showing the cam of the door closer. [Figure 6] 1A and 1B are perspective views showing the main parts of the door closer, in which FIG. 1A shows the door in a closed state and FIG. 1B shows the door at a 45-degree opening angle. [Figure 7] 1A and 1B are perspective views showing the main parts of the door closer, in which FIG. 1A shows the state where the door is opened at an 80-degree angle, and FIG. 1B shows the state where the door is opened at an 120-degree angle. [Figure 8]This shows the main parts of the door closer in the closed state, with (a) being a cross-sectional view from above and (b) being a cross-sectional view from the front. [Figure 9] This shows the case where the door opening angle at the key part of the door closer is 45 degrees, (a) is a cross-sectional view from the top, and (b) is a cross-sectional view from the front. [Figure 10] This shows the case where the door opening angle at the key part of the door closer is 80 degrees, (a) is a cross-sectional view from the top, and (b) is a cross-sectional view from the front. [Figure 11] This shows the case where the door opening angle at the key part of the door closer is 120 degrees, (a) is a cross-sectional view from the top, and (b) is a cross-sectional view from the front. [Figure 12] 6 is a graph showing the relationship between the door opening angle and the amount of movement of the slider. [Figure 13] Graph showing the relationship between door opening angle and closing force. [Figure 14] 10 is a graph showing the relationship between the door opening angle and the movement amount of the buffer piston. [Figure 15] FIG. 10 is a cross-sectional view of a main part of a door closer according to another embodiment of the present invention. [Figure 16] FIG. 10 is a cross-sectional view of a main part of a door closer according to another embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0016] A door closer according to one embodiment of the present invention will be described below with reference to FIGS. 1 to 14. As shown in FIG. 1, the door closer in this embodiment includes a door closer main body 1, a mounting plate 2, and an arm 3. The door closer is of a sliding type. Note that hatching is omitted in FIG. 1(b) and other figures. The door closer main body 1 is attached to a door or a door frame. The door rotates around an axis in the up-down direction. When the door closer main body 1 is attached to the door, a rail (not shown) extending in the left-right direction (horizontal direction) is attached to the door frame. The door closer of this embodiment is of a concealed type, and the door closer main body 1 is placed inside the door. The door closer main body 1 is screwed to the door via the mounting plate 2. The mounting plate 2 is screwed to the top surface of the door closer main body 1. Note that the left-right direction is the direction along the surface of the door and is the radial direction with respect to the center of rotation of the door. Furthermore, the front-rear direction is the normal direction to the surface of the door. In this embodiment, the up-down direction is the first direction, and the left-right direction is the second direction.

[0017] Fig. 1 shows the door closer when the door is fully closed. The door closer body 1 includes a housing 10, a main shaft 11, a cam 12, a transmission roller 13, a slider 14, a first spring 15 and a second spring 16 as closing springs, a buffer roller 17, a buffer piston 18, and a third spring 19 as a buffer spring.

[0018] The housing 10 has a rectangular parallelepiped shape that is long in the left-right direction as a whole. In Fig. 1, the right side as you face it will be simply referred to as the right side, and the left side as you face it will be simply referred to as the left side. In this embodiment, the rotation center of the door is located on the left side of the door closer main body 1, but it may also be located on the right side.

[0019] The housing 10 has one accommodation chamber 20 extending in the left-right direction. The housing 10 has openings at both left and right ends, and both left and right openings are sealed by end caps 21. The space between the left and right end caps 21 forms the accommodation chamber 20, which is filled with hydraulic oil. The accommodation chamber 20 contains a slider 14, a transmission roller 13, a first spring 15, a second spring 16, a buffer roller 17, a buffer piston 18, and a third spring 19. The mounting plate 2 is fixed to the housing 10 with screws.

[0020] The inner surface of housing 10 is the wall surface of accommodation chamber 20. The wall surface of accommodation chamber 20 is a peripheral surface that is circular in cross section except for the vicinity of main shaft 11. Accommodation chamber 20 has a first center line T1 that extends in the left-right direction. In a plan view, main shaft 11, transmission roller 13, slider 14, first spring 15, second spring 16, buffer roller 17, buffer piston 18, and third spring 19 are arranged on first center line T1 of accommodation chamber 20. Therefore, main shaft 11, transmission roller 13, slider 14, first spring 15, second spring 16, buffer roller 17, buffer piston 18, and third spring 19 are positioned on the same line that extends along the left-right direction in a plan view. 1(b) , the slider 14, the first spring 15, the second spring 16, the buffer piston 18, and the third spring 19 are located on the same line (on the first center line T1) along the left-right direction and at the same height in the up-down direction. The transmission roller 13, the slider 14, the first spring 15, and the second spring 16 are located on the right side of the main shaft 11, and the buffer roller 17, the buffer piston 18, and the third spring 19 are located on the opposite side, that is, the left side, of the main shaft 11.

[0021] The axial direction of the main shaft 11 is the vertical direction. The main shaft 11 rotates around its vertical axis. The main shaft 11 is rotatably supported by the housing 10. As shown in Figure 1, the main shaft 11 is positioned to the left of the center of the housing 10 in the horizontal direction. As shown in Figure 1(a), the main shaft 11 is located approximately in the center of the housing 10 in the front-to-rear direction. The upper end of the main shaft 11 protrudes upward from the housing 10 and also protrudes upward from the mounting plate 2. A first end of the arm 3 is attached to the upper end of the main shaft 11 so as not to rotate relative to it. A second end of the arm 3 is engaged with the rail described above. When the door rotates, the second end of the arm 3 slides left and right while being guided by the rail. The main shaft 11 rotates together with the arm 3 as the door opens and closes.

[0022] A first bearing holder 22 and a second bearing holder 23 are attached to the top and bottom surfaces of the housing 10, respectively. The main shaft 11 is rotatably supported by the first bearing holder 22 and the second bearing holder 23 via bearings. As shown in FIGS. 2 and 3, the main shaft 11 is composed of two separate upper and lower members. That is, the main shaft 11 is composed of a first shaft member 11a located on the upper side and a second shaft member 11b located on the lower side. FIG. 2 is an exploded view of the main parts showing the relationship between the main shaft 11 and cam 12, the slider 14 and transmission roller 13, the buffer piston 18 and buffer roller 17. FIG. 3 is a perspective view of the main shaft 11, where (a) shows only the second shaft member 11b, and (b) shows the first shaft member 11a attached to the second shaft member 11b. The first shaft member 11a and the second shaft member 11b are detachably connected to each other at the top and bottom. The first shaft member 11a and the second shaft member 11b are unable to rotate relative to each other, but rotate as a unit.

[0023] The first shaft member 11a is rotatably supported by a first bearing holder 22, and the second shaft member 11b is rotatably supported by a second bearing holder 23. A cam 12 is provided on the second shaft member 11b. The cam 12 is provided integrally with the second shaft member 11b, but may be a separate member.

[0024] <Cam 12> The cam 12 has a two-stage structure, consisting of two plate cams arranged one above the other. The cam 12 is made up of an upper cam 12a located on the upper side and a lower cam 12b located on the lower side. The upper cam 12a and the lower cam 12b rotate integrally together with the main shaft 11. The upper cam 12a and the lower cam 12b have different shapes. The upper cam 12a and the lower cam 12b are adjacent to each other vertically. The upper cam 12a is located above the first center line T1, and the lower cam 12b is located below the first center line T1. Although the upper cam 12a and the lower cam 12b are integrally formed, they may also be separate components.

[0025] Figures 4 and 5 show the details of the upper cam 12a and the lower cam 12b. Figure 4 is a plan view showing the shape of the cam surfaces of the upper cam 12a and the lower cam 12b, Figure 5(a) is a plan view showing the shape of the cam surface of the upper cam 12a, and Figure 5(b) is a plan view showing the shape of the cam surface of the lower cam 12b. Both Figures 4 and 5 show the closed door state (0 degrees), and the door opens counterclockwise as viewed from the paper. The rotation direction of the main shaft 11 and cam 12 when the door opens is indicated by arrow P. Furthermore, the center line of the main shaft 11, which is the center of the cam 12, is indicated by symbol Q.

[0026] The upper cam 12a has a first peripheral surface 30. A second transmission cam surface 31 and a first buffer cam surface 32 are provided on the first peripheral surface 30. The second transmission cam surface 31 extends from a start point 31a to an end point 31b. The first buffer cam surface 32 extends from a start point 32a to an end point 32b. The second transmission cam surface 31 and the first buffer cam surface 32 are both located on the left side of the entire circumference of the first peripheral surface 30. The second transmission cam surface 31 and the first buffer cam surface 32 are provided at different positions on the first peripheral surface 30 and are spaced apart from each other in the circumferential direction. In a plan view, the second transmission cam surface 31 is located forward of a second center line T2 that passes through the center line of the main shaft 11 and extends in the left-right direction, and is located left of a third center line T3 that passes through the center line of the main shaft 11 and extends in the front-rear direction. The first buffer cam surface 32 is located rearward of the second center line T2 and leftward of the third center line T3. The second transmission cam surface 31 and the first buffer cam surface 32 are located on opposite sides of the second center line T2 in the front-to-rear direction.

[0027] The lower cam 12b has a second peripheral surface 33. A first transmission cam surface 34 and a second buffer cam surface 35 are provided on the second peripheral surface 33. The first transmission cam surface 34 extends from a starting point 34a to an end point 34b. The second buffer cam surface 35 extends from a starting point 35a to an end point 35b. The first transmission cam surface 34 and the second buffer cam surface 35 are provided at different positions on the second peripheral surface 33 and are spaced apart from each other in the circumferential direction. The first transmission cam surface 34 is located forward of the second center line T2 and straddles the third center line T3. The second buffer cam surface 35 is located rearward of the second center line T2 and straddles the third center line T3. The first transmission cam surface 34 and the second buffer cam surface 35 are located on opposite sides of each other in the front-to-rear direction with respect to the second center line T2.

[0028] The upper cam 12a and lower cam 12b having such shapes are stacked one on top of the other as shown in Figure 4. The first transmission cam surface 34 and the second transmission cam surface 31 are both located forward of the second center line T2. The first transmission cam surface 34 and the second transmission cam surface 31 are provided at different circumferential positions from each other, with the second transmission cam surface 31 located downstream of the first transmission cam surface 34 in the direction of rotation of the main shaft 11 during the door-opening operation. The first buffer cam surface 32 and the second buffer cam surface 35 are both located rearward of the second center line T2. The first buffer cam surface 32 and the second buffer cam surface 35 are provided at different circumferential positions from each other, with the second buffer cam surface 35 located downstream of the first buffer cam surface 32 in the direction of rotation of the main shaft 11 during the door-opening operation. The starting point 34a of the first transmission cam surface 34 is located on the right side, and the starting point 32a of the first buffer cam surface 32 is located on the left side. The starting point 34a of the first transmission cam surface 34 and the starting point 32a of the first buffer cam surface 32 are both located on the second center line T2 and are positioned 180 degrees opposite each other.

[0029] <Transmission roller 13 and slider 14> The slider 14 has a cylindrical shape with the first center line T1 as its axis. The slider 14 abuts against the wall surface of the accommodation chamber 20 (the inner surface of the housing 10) and is supported by the wall surface of the accommodation chamber 20. When the slider 14 moves in the left-right direction, it is guided by the wall surface of the accommodation chamber 20 and slides along the wall surface of the accommodation chamber 20. The slider 14 is formed with a through-hole (not shown) for communicating hydraulic oil in the left-right direction.

[0030] The transmission roller 13 is disposed on the left side of the slider 14. A first support shaft 40 having an axis extending in the vertical direction is attached to the slider 14. The transmission roller 13 is rotatably supported on the first support shaft 40 via a bearing. The transmission roller 13 rotates in contact with the cam 12. The transmission roller 13 is a cam follower. The transmission roller 13 has two stages, an upper stage and an lower stage, corresponding to the cam 12. The transmission roller 13 has an upper transmission roller 13a facing the upper cam 12a and a lower transmission roller 13b facing the lower cam 12b. The upper transmission roller 13a is a second transmission follower, and the lower transmission roller 13b is a first transmission follower. The upper transmission roller 13a and the lower transmission roller 13b are coaxial with each other. The upper transmission roller 13a has a larger diameter than the lower transmission roller 13b. The upper transmission roller 13a and the lower transmission roller 13b are formed integrally with each other, but may be separate bodies. The upper transmission roller 13a and the lower transmission roller 13b are adjacent to each other vertically. The upper transmission roller 13a is located above the first center line T1, and the lower transmission roller 13b is located below the first center line T1. The first transmission cam surface 34 of the lower cam 12b, the second transmission cam surface 31 of the upper cam 12a, the upper transmission roller 13a, and the lower transmission roller 13b form a first cam switching mechanism for generating a closing force.

[0031] The transmission roller 13 and slider 14 move together in the left-right direction. When the door opens, the slider 14 is pushed to the right by the cam 12, compressing the first spring 15 and the second spring 16. When the door closes, the slider 14 is pushed to the left by the elastic restoring forces of the first spring 15 and the second spring 16, causing the main shaft 11 to generate a closing force for closing the door. A key groove 41 is provided on the outer peripheral surface of the slider 14 along the left-right direction. A restriction pin 42, the tip of which protrudes into the accommodation chamber 20, is attached to the housing 10. The tip of the restriction pin 42 engages with the key groove 41. This restricts the rotation of the slider 14 around the axis in the left-right direction relative to the housing 10. In other words, the restriction pin 42 functions as a rotation stopper for the slider 14. A locking pin 43 is attached to the right end surface of the slider 14. The end of the locking pin 43 protrudes from the right end surface of the slider 14, and the first spring 15 is locked to the protruding portion.

[0032] <First spring 15 and second spring 16> The first spring 15 and the second spring 16 are disposed on the right side of the slider 14. The first spring 15 and the second spring 16 bias the slider 14 to the left, i.e., toward the main shaft 11. The first spring 15 and the second spring 16 are coil springs and compression springs. The first spring 15 is interposed between the slider 14 and the spring retainer 44. The left end of the first spring 15 abuts against the right end surface of the slider 14. The left end of the first spring 15 is engaged with a locking pin 43, which restricts the rotation of the first spring 15 around its axis in the left-right direction. The spring retainer 44 is located on the right side of the first spring 15. The right end of the first spring 15 abuts against the spring retainer 44. The locking pin 43 is attached to the left end surface of the spring retainer 44. The right end of the first spring 15 is locked to the locking pin 43, and the locking pin 43 restricts the relative rotation of the first spring 15 and the spring presser 44 around the axis in the left-right direction.

[0033] The second spring 16 is interposed radially inside the first spring 15. The second spring 16 has a smaller diameter than the first spring 15. The second spring 16 is weaker than the first spring 15, and the spring force of the second spring 16 is smaller than the spring force of the first spring 15. The first spring 15 is the main spring, and the second spring 16 is the sub-spring. The second spring 16 is also located between the slider 14 and the spring retainer 44.

[0034] The spring retainer 44 is guided by the wall surface of the accommodation chamber 20 and is movable in the left-right direction. An adjustment shaft 45 passes through the spring retainer 44 in the left-right direction. The adjustment shaft 45 has a male thread portion that is screwed into the female thread portion of the spring retainer 44. The spring retainer 44 can be moved in the left-right direction by rotating the adjustment shaft 45. When the spring retainer 44 moves to the left, the first spring 15 and the second spring 16 are compressed, and the spring force becomes stronger. Conversely, when the spring retainer 44 moves to the right, the amount of compression of the first spring 15 and the second spring 16 decreases, and the spring force becomes weaker.

[0035] The adjustment shaft 45 passes through the right end cap 21. The adjustment shaft 45 is rotatably supported by the end cap 21. The right end of the adjustment shaft 45 protrudes outside the end cap 21, and a first adjustment gear 46 is attached to that right end. The first adjustment gear 46 meshes with a second adjustment gear 47. The second adjustment gear 47 is located below the mounting plate 2. An operation shaft 48 is rotatably supported by the mounting plate 2. The second adjustment gear 47 is attached to the lower end of the operation shaft 48. The second adjustment gear 47 can be rotated by rotating the operation shaft 48 from above the mounting plate 2. By rotating the first adjustment gear 46 via the second adjustment gear 47, the adjustment shaft 45 can be rotated, and the spring holder 44 can be moved left and right. In this embodiment, the spring presser 44, the adjustment shaft 45, the first adjustment gear 46, the second adjustment gear 47, and the operation shaft 48 constitute a spring force adjustment mechanism.

[0036] The accommodation chamber 20 accommodates a foam rubber 49. The foam rubber 49 is for absorbing expansion caused by a rise in temperature of the hydraulic oil. The foam rubber 49 is, for example, rod-shaped. The foam rubber 49 is, for example, disposed radially inside the second spring 16.

[0037] <Buffer roller 17 and buffer piston 18> The buffer piston 18 is cylindrical with its axis coincident with the first center line T1. The buffer piston 18 abuts against the wall surface of the accommodation chamber 20 (the inner surface of the housing 10) and is supported by the wall surface of the accommodation chamber 20. When the buffer piston 18 moves in the left-right direction, it is guided by the wall surface of the accommodation chamber 20 and slides along the wall surface of the accommodation chamber 20.

[0038] The buffer roller 17 is disposed to the right of the buffer piston 18. The buffer roller 17 and buffer piston 18 move together in the left-right direction. A second support shaft 50 having an axis in the vertical direction is attached to the right of the buffer piston 18. The buffer roller 17 is rotatably supported on the second support shaft 50. The buffer roller 17 rotates in contact with the cam 12. The buffer roller 17 is a cam follower. The buffer roller 17 is located on the opposite side of the main shaft 11 from the transmission roller 13 in the left-right direction. The buffer roller 17 and transmission roller 13 face each other in the left-right direction with the main shaft 11 in between.

[0039] The buffer rollers 17 are configured in two stages, upper and lower, corresponding to the cams 12. The buffer rollers 17 have an upper buffer roller 17a facing the upper cam 12a and a lower buffer roller 17b facing the lower cam 12b. The upper buffer roller 17a is a first buffer follower, and the lower buffer roller 17b is a second buffer follower. The upper buffer roller 17a and the lower buffer roller 17b are coaxial with each other. The upper buffer roller 17a has a larger diameter than the lower buffer roller 17b. The upper buffer roller 17a has a smaller diameter than the upper transmission roller 13a, and the lower buffer roller 17b has a smaller diameter than the lower transmission roller 13b. The upper buffer roller 17a and the lower buffer roller 17b are formed integrally with each other, but may be separate bodies. The upper buffer roller 17a and the lower buffer roller 17b are adjacent to each other vertically. The upper buffer roller 17a is located above the first center line T1, and the lower buffer roller 17b is located below the first center line T1. The first buffer cam surface 32 of the upper cam 12a, the second buffer cam surface 35 of the lower cam 12b, the upper buffer roller 17a, and the lower buffer roller 17b form a second cam switching mechanism for controlling the door closing speed.

[0040] The buffer piston 18 divides the storage chamber 20 into two regions, left and right. The housing 10 is provided with a flow control passage (not shown) for controlling the door-closing speed. The buffer piston 18 buffers the door-closing operation by forcing hydraulic oil into the flow control passage during the door-closing operation. The buffer piston 18 is provided with a buffer head 51 on the left side of the second support shaft 50. The buffer piston 18 has a spring hole 52 that opens to its left end face. The buffer head 51 is inserted into and fixed in the spring hole 52. A communication hole 53 is formed on the right side of the spring hole 52, penetrating the spring hole 52 and the region of the storage chamber 20 to the right of the buffer piston 18 in the left-right direction.

[0041] A third spring 19 is positioned in the spring hole 52. The third spring 19 is interposed between the buffer head 51 and the left end cap 21. The third spring 19 is a coil spring and a compression spring. The third spring 19 urges the buffer head 51 to the right. The buffer piston 18 is urged to the right by the third spring 19. The third spring 19 is weaker than the first spring 15 and the second spring 16.

[0042] A through-hole 54 is formed in the center of the buffer head 51 along the left-right direction. The through-hole 54 is adjacent to the communication hole 53 and communicates with the communication hole 53. A check valve is provided in the through-hole 54. During the door-opening operation, the buffer piston 18 moves to the right. During the door-opening operation, a ball 55, which serves as the valve body of the check valve, moves to the left, opening the valve and allowing hydraulic oil to pass through the through-hole 54. On the other hand, during the door-closing operation, the buffer piston 18 moves to the left. During the door-closing operation, the check valve ball 55 is pushed to the right by the hydraulic pressure of the hydraulic oil, closing the through-hole 54 and preventing hydraulic oil from passing through the through-hole 54. During the door-closing operation, hydraulic oil is pushed to the left by the buffer piston 18 and forced into the flow control flow path, which serves as a bypass. The hydraulic oil travels through the flow control flow path to the area to the right of the buffer piston 18. An adjustment valve 56 is provided in the flow control flow path to control the flow rate of hydraulic oil flowing through the flow control flow path. The adjustment valve 56 is adjustable from the top of the housing 10. By controlling the flow rate of the hydraulic oil flowing through the flow rate control passage, the degree of cushioning during the door closing operation can be adjusted.

[0043] A key groove 41 is provided on the outer peripheral surface of the buffer piston 18 along the left-right direction. A restricting pin 42 with a tip end protruding into the accommodation chamber 20 is attached to the housing 10. The tip end of the restricting pin 42 engages with the key groove 41. This restricts the rotation of the buffer piston 18 around the axis in the left-right direction relative to the housing 10. In other words, the restricting pin 42 functions as a rotation stopper for the buffer piston 18.

[0044] <Door opening action> Next, the operation of the door as it opens from the closed state will be described in order. Figures 6(a) and 8 show the closed door state. In the closed door state, the upper cam 12a abuts against the upper buffer roller 17a but does not abut against the upper transmission roller 13a. The first buffer cam surface 32 of the upper cam 12a abuts against the upper transmission roller 13a. The lower cam 12b abuts against the lower transmission roller 13b but does not abut against the lower buffer roller 17b. The first transmission cam surface 34 of the lower cam 12b abuts against the lower transmission roller 13b. In the closed door state, the slider 14 is moved to the leftmost position, the first spring 15 and the second spring 16 are in their most extended states, the buffer piston 18 is moved to the leftmost position, and the third spring 19 is in their most compressed state.

[0045] As the door opens, the main shaft 11 rotates together with the arm 3, and the upper cam 12a and lower cam 12b rotate together with the main shaft 11. The first transmission cam surface 34 of the lower cam 12b pushes the lower transmission roller 13b to the right, causing the slider 14 to slide to the right. The slider 14 pushes and compresses the first spring 15 and the second spring 16. The first transmission cam surface 34 moves the lower transmission roller 13b significantly to the right, particularly at the beginning of opening, causing the first spring 15 and the second spring 16 to compress significantly.

[0046] The first buffer cam surface 32 of the upper cam 12a has the longest distance from the center of the cam 12 at its starting point 32a. As the upper cam 12a rotates, the distance of the first buffer cam surface 32 from the center of the cam 12 gradually decreases. As a result, the buffer piston 18 is pushed to the right by the third spring 19 and moves.

[0047] <Buffer switching angle> 6(b) and 9 show the state when the door is opened at a 45-degree angle. In this embodiment, the door opening angle of 45 degrees is the buffer switching angle. In this state, the first transmission cam surface 34 of the lower cam 12b continues to contact the lower transmission roller 13b. The upper cam 12a does not contact the upper transmission roller 13a. Meanwhile, the first buffer cam surface 32 of the upper cam 12a reaches its end point 32b and ends contact with the upper buffer roller 17a. Conversely, the start point 35a of the second buffer cam surface 35 of the lower cam 12b contacts the lower buffer roller 17b. That is, at a 45-degree opening angle, the contact state between the first buffer cam surface 32 and the upper buffer roller 17a ends, and the contact state between the second buffer cam surface 35 and the lower buffer roller 17b begins. In this way, at a 45-degree opening angle, the cam surface switches from the first buffer cam surface 32 to the second buffer cam surface 35. Therefore, the buffer piston 18 can continue to move to the right.

[0048] <Transmission switching angle> 7(a) and 10 show the state where the door opening angle (door opening angle) is 80 degrees. In this embodiment, the door opening angle of 80 degrees is the transmission switching angle. In this state, the first transmission cam surface 34 of the lower cam 12b reaches its end point 34b and ends contact with the lower transmission roller 13b. Conversely, the start point 31a of the second transmission cam surface 31 of the upper cam 12a contacts the upper transmission roller 13a. That is, at an opening angle of 80 degrees, the contact state between the first transmission cam surface 34 and the lower transmission roller 13b ends, and the contact state between the second transmission cam surface 31 and the upper transmission roller 13a begins. In this way, at an opening angle of 80 degrees, the cam surface switches from the first transmission cam surface 34 to the second transmission cam surface 31. Therefore, the slider 14 can continue to move to the right, and the first spring 15 and the second spring 16 can be compressed by the slider 14. On the other hand, the second buffer cam surface 35 of the lower cam 12b continues to contact the lower buffer roller 17b, and the upper cam 12a does not contact the upper buffer roller 17a.

[0049] <Maximum movement angle> Figures 7(b) and 11 show the state when the door is opened at an angle of 120 degrees. In this state, the second transmission cam surface 31 of the upper cam 12a continues to contact the upper transmission roller 13a, but the second transmission cam surface 31 reaches near its end point 31b. The lower cam 12b does not contact the lower transmission roller 13b. The slider 14 is close to its maximum movement state to the right. Meanwhile, the second buffer cam surface 35 of the lower cam 12b continues to contact the lower buffer roller 17b, but the second buffer cam surface 35 reaches near its end point 35b. The upper cam 12a does not contact the upper buffer roller 17a. The buffer piston 18 is close to its maximum movement state to the right. Furthermore, after this, even if the door opening angle exceeds 120 degrees, within a small range, the second transmission cam 12 of the upper cam 12a abuts against the upper transmission roller 13a, and the second buffer cam surface 35 of the lower cam 12b abuts against the lower buffer roller 17b.

[0050] FIG. 12 shows the relationship between the door opening angle and the amount of movement of the slider 14. In this graph, the upper line (two-stage cam) shows the amount of movement of the slider 14 in this embodiment, and the lower line (single cam) shows the amount of movement of the slider 14 in a configuration in which the cam 12 is configured with a single cam and does not have a cam switching mechanism. As such, the two-stage cam can move the slider 14 even at relatively large opening angles compared to a single cam, thereby compressing the first spring 15 and the second spring 16. FIG. 13 shows the relationship between the door opening angle and the closing force (torque). As can be seen from this graph, the two-stage cam has an improved closing force at opening angles of 80 degrees or more compared to a single cam. Furthermore, with the two-stage cam, the closing force peaks around 90 degrees.

[0051] 14 shows the relationship between the door opening angle and the amount of movement of the buffer piston 18. In this way, the configuration of the upper and lower two-stage cam 12 can increase the amount of movement of the buffer piston 18 over the entire range compared to a single cam configuration without a cam switching mechanism. Therefore, the flow rate of the hydraulic oil flowing through the flow control flow path can be increased, making it easier to adjust the door closing speed.

[0052] In this embodiment, the upper transmitting rollers 13a have a larger diameter than the lower transmitting rollers 13b. However, for example, the upper transmitting rollers 13a and the lower transmitting rollers 13b may have the same diameter, or the upper transmitting rollers 13a may have a smaller diameter than the lower transmitting rollers 13b. As an example, FIG. 15 shows a case where the upper transmitting rollers 13a and the lower transmitting rollers 13b have the same diameter. In this case, the upper transmitting rollers 13a and the lower transmitting rollers 13b are not coaxial, but have different support shafts. That is, the upper support shaft 60 supporting the upper transmitting rollers 13a is closer to the main shaft 11 than the lower support shaft 61 supporting the lower transmitting rollers 13b, and the upper transmitting rollers 13a are closer to the main shaft 11 than the lower transmitting rollers 13b. The same applies to the upper buffer rollers 17a and the lower buffer rollers 17b. The upper buffer rollers 17a and the lower buffer rollers 17b may have the same diameter, or the upper buffer rollers 17a may have a smaller diameter than the lower buffer rollers 17b.

[0053] Furthermore, while the cam 12, transmission rollers 13, and buffer rollers 17 are configured in two vertical stages, they may also be configured in three vertical stages. For example, as shown in FIG. 16, the cam 12 may be configured as three plate cams, namely, a first cam 71, a second cam 72, and a third cam 73, from top to bottom. In this case, the first cam 71 and the third cam 73 may have the same shape and replace the upper cam 12a, and the second cam 72 may replace the lower cam 12b. The transmission rollers 13 may be configured as, from top to bottom, a first transmission roller 81, a second transmission roller 82, and a third transmission roller 83. In this case, the first transmission roller 81 and the third transmission roller 83 may have the same diameter and replace the upper transmission roller 13a, and the second transmission roller 82 may replace the lower transmission roller 13b. The buffer rollers 17 may be configured as, from top to bottom, a first buffer roller 91, a second buffer roller 92, and a third buffer roller 93. In this case, the first buffer rollers 91 and the third buffer rollers 93 may have the same diameter and may be used in place of the upper buffer rollers 17a, and the second buffer rollers 92 may be used in place of the lower buffer rollers 17b. In this way, it is also preferable to have a vertically symmetrical configuration.

[0054] While the upper cam 12a is provided with the second transmission cam surface 31 and the first buffer cam surface 32, the second transmission cam surface 31 and the first buffer cam surface 32 may be provided separately above and below. That is, the second transmission cam surface 31 and the first buffer cam surface 32 may be provided separately on different circumferential surfaces. For example, the first upper cam and the second upper cam may be provided with the second transmission cam surface 31 and the first buffer cam surface 32, respectively. Similarly, the lower cam 12b is provided with the first transmission cam surface 34 and the second buffer cam surface 35, but the first transmission cam surface 34 and the second buffer cam surface 35 may be provided separately above and below. That is, the first transmission cam surface 34 and the second buffer cam surface 35 may be provided separately on different circumferential surfaces. For example, the first transmission cam surface 34 and the second buffer cam surface 35 may be provided respectively on the first lower cam and the second lower cam. Furthermore, the transmission rollers 13 and the buffer rollers 17 may also be provided in multiple levels above and below.

[0055] Furthermore, although a cam switching mechanism is provided on both the slider 14 side and the buffer piston 18 side, it may be provided only on the slider 14 side or only on the buffer piston 18 side. Also, the buffer piston 18 may be driven by a mechanism other than the cam 12, or the slider 14 may be driven by a mechanism other than the cam 12. [Explanation of symbols]

[0056] 1 Door closer body 2 Mounting Plate 3 Arm 10. Housing 11 Spindle 11a First shaft member 11b Second shaft member 12 Cam 12a upper cam 12b Lower Cam 13 Transmission roller 13a Upper transmission roller (second transmission follower) 13b Lower transmission roller (first transmission follower) 14 Slider 15 First spring (closing spring) 16 Second spring (closing spring) 17 Buffer roller 17a Upper buffer roller (first buffer follower) 17b Lower buffer roller (second buffer follower) 18 Buffer piston 19 Third spring (buffer spring) 20 Containment Room 21 End cap 22 First bearing holder 23 Second bearing holder 30 First peripheral surface 31 Second transmission cam surface 32 First buffer cam surface 33 Second peripheral surface 34 First transmission cam surface 35 Second buffer cam surface 40 1st spindle 41 Keyway 42 Regulatory pin 43 Locking pin 44 Spring holder 45 Adjustment axis 46 First adjusting gear 47 Second adjusting gear 48 Operation axis 49 Foam rubber 50 2nd spindle 51 Buffer head 52 Spring hole 53 Communication hole 54 Through hole 55 balls 56 Regulating valve 60 Upper support shaft 61 Lower support shaft 71 First Cam 72 Second Cam 73 Third Cam 81 First Transmission Roller 82 Second transmission roller 83 Third Transmission Roller 91 First shock absorber roller 92 Second shock absorber roller 93 Third shock absorber roller T1 1st center line T2 2nd center line T3 3rd Cancellation Line

Claims

1. a main shaft that rotates around an axis in a first direction in accordance with the opening and closing operation of the door; a cam provided on the main shaft and rotating together with the main shaft; a transmission roller that contacts the cam; a slider that moves together with the transmission roller in a second direction perpendicular to the first direction in accordance with the rotation of the main shaft; a closing spring that is elastically deformed by the slider when the door is opened and returns to its original shape when the door is closed, and applies a closing force to the main shaft via the slider; Equipped with the cam has a first transmission cam surface and a second transmission cam surface provided at different positions in the first direction; The transmission roller has a first transmission follower facing the first transmission cam surface and a second transmission follower facing the second transmission cam surface, From the closed state to the predetermined transmission switching angle, the first transmission cam surface contacts the first transmission follower, and the second transmission cam surface does not contact the second transmission follower, At the transmission switching angle, the state where the first transmission cam surface contacts the first transmission follower is switched to the state where the second transmission cam surface contacts the second transmission follower, At an opening angle greater than the transmission switching angle, the first transmission cam surface does not contact the first transmission follower, and the second transmission cam surface contacts the second transmission follower.

2. 2. The door closer according to claim 1, wherein the first transmission follower and the second transmission follower are provided coaxially with each other, and the second transmission follower has a larger diameter than the first transmission follower.

3. a main shaft that rotates around an axis in a first direction in accordance with the opening and closing operation of the door; a cam provided on the main shaft and rotating together with the main shaft; a buffer roller that contacts the cam; a buffer piston that moves together with the buffer roller in a second direction perpendicular to the first direction as the main shaft rotates to buffer the closing operation of the door; a buffer spring that biases the buffer piston toward the spindle; Equipped with the cam has a first buffer cam surface and a second buffer cam surface provided at different positions in the first direction; The buffer roller has a first buffer follower facing the first buffer cam surface and a second buffer follower facing the second buffer cam surface, From the closed door state to a predetermined buffer switching angle, the first buffer cam surface contacts the first buffer follower, and the second buffer cam surface does not contact the second buffer follower; At the buffer switching angle, the first buffer cam surface switches from contacting the first buffer follower to contacting the second buffer follower, At an opening angle greater than the buffer switching angle, the first buffer cam surface does not contact the first buffer follower, and the second buffer cam surface contacts the second buffer follower.

4. 4. The door closer according to claim 3, wherein the first buffer follower and the second buffer follower are arranged coaxially with each other, and the first buffer follower has a larger diameter than the second buffer follower.

5. a main shaft that rotates around an axis in a first direction in accordance with the opening and closing operation of the door; a cam provided on the main shaft and rotating together with the main shaft; a transmission roller that contacts the cam; a slider that moves together with the transmission roller in a second direction perpendicular to the first direction in accordance with the rotation of the main shaft; a closing spring that is elastically deformed by the slider when the door is opened and returns to its original shape when the door is closed, and applies a closing force to the main shaft via the slider; a buffer roller that contacts the cam; a buffer piston that moves in the second direction together with the buffer roller as the main shaft rotates to buffer the closing operation of the door; a buffer spring that biases the buffer piston toward the spindle; Equipped with the cam has a first transmission cam surface and a second transmission cam surface provided at positions different from each other in the first direction, and a first buffer cam surface and a second buffer cam surface provided at positions different from each other in the first direction, The transmission roller has a first transmission follower facing the first transmission cam surface and a second transmission follower facing the second transmission cam surface, From the closed state to the predetermined transmission switching angle, the first transmission cam surface contacts the first transmission follower, and the second transmission cam surface does not contact the second transmission follower, At the transmission switching angle, the state where the first transmission cam surface contacts the first transmission follower is switched to the state where the second transmission cam surface contacts the second transmission follower, At an opening angle greater than the transmission switching angle, the first transmission cam surface does not contact the first transmission follower, and the second transmission cam surface contacts the second transmission follower, The buffer roller has a first buffer follower facing the first buffer cam surface and a second buffer follower facing the second buffer cam surface, From the closed door state to a predetermined buffer switching angle, the first buffer cam surface contacts the first buffer follower, and the second buffer cam surface does not contact the second buffer follower; At the buffer switching angle, the first buffer cam surface switches from contacting the first buffer follower to contacting the second buffer follower, At an opening angle greater than the buffer switching angle, the first buffer cam surface does not contact the first buffer follower, and the second buffer cam surface contacts the second buffer follower.

6. the first transmitting cam surface and the second buffering cam surface are provided at different positions in the circumferential direction on the first peripheral surface of the cam; 6. The door closer according to claim 5, wherein the second transmitting cam surface and the first buffering cam surface are provided at different positions in the circumferential direction on the second peripheral surface of the cam.

Images