Rotary damper

Abstract

This invention can improve the responsiveness of the valve and significantly reduce the oil resistance acting on the vane when the valve core receives oil pressure from the opposite direction. The present invention provides a rotary damper having a first valve (12) disposed in a first oil passage (11). The rotary damper comprises: an oil chamber (7) filled with oil; a vane (6) located in the oil chamber (7); a groove (14) formed on the vane (6) and functioning as the valve body of the first valve (12); a valve core (15) of the first valve (12) that moves while in contact with the bottom surface (17) of the groove (14); and an elastic body (29) that imparts elastic force to the valve core (15) so that the valve core (15) contacts the wall surface (13) of the oil chamber (7) when there is no oil flow. The bottom surface (17) of the groove (14) is inclined, thereby the valve core (15) which contacts the wall surface (13) of the oil chamber (7) when receiving oil pressure from one direction separates from the wall surface (13) of the oil chamber (7) when receiving oil pressure from the opposite direction.

Description

Technical Field

[0001] The present invention relates to a rotary damper having a valve disposed in an oil circuit. Background Technology

[0002] Patent Document 1 discloses a rotary damper having a valve disposed in an oil passage. This rotary damper includes: an oil chamber filled with oil, a vane located in the oil chamber, a groove formed on the vane and functioning as an oil passage, a valve core that moves while contacting the end face of the vane, and an elastic body that imparts elastic force to the valve core so that the valve core contacts one face of the vane when there is no oil flow. The valve core contacts one face of the vane when receiving oil pressure from one direction, and separates from one face of the vane when receiving oil pressure from the opposite direction. This rotary damper improves the responsiveness of the valve by imparting elastic force to the valve core with the elastic body. However, this rotary damper is configured such that the groove formed on the vane functions as an oil passage, and the valve core, by blocking the groove, receives oil pressure from the opposite direction and separates from one face of the vane. The elastic body deforms when the valve core separates from one face of the vane, but the deformation of the elastic body is limited, thus the gap formed between the valve core and one face of the vane is relatively narrow. Therefore, the flow rate of oil through the groove is limited by the narrow gap. Consequently, in this rotary damper, the resistance of the oil acting on the vane when the valve core receives oil pressure from the opposite direction cannot be sufficiently reduced.

[0003] Patent Document 1: Japanese Patent Application Publication No. 2000-120747 Summary of the Invention

[0004] The present invention was made in view of the above situation, and its object is to improve the responsiveness of the valve and to sufficiently reduce the resistance of the oil acting on the vane when the valve core receives oil pressure from the opposite direction.

[0005] To address the aforementioned issues, the present invention provides a rotary damper having a first valve disposed in a first oil passage. The rotary damper comprises: an oil chamber filled with oil; a vane located in the oil chamber; a groove formed in the vane and functioning as the valve body of the first valve; a valve core of the first valve that moves while in contact with the bottom surface of the groove; and an elastic body that imparts elastic force to the valve core so that the valve core contacts the wall of the oil chamber when there is no oil flow. The bottom surface of the groove is inclined, thereby causing the valve core, which is in contact with the wall of the oil chamber when receiving oil pressure from one direction, to separate from the wall of the oil chamber when receiving oil pressure from the opposite direction.

[0006] The rotary damper according to the present invention includes an elastic body that imparts elastic force to the valve core and contacts the wall of the oil chamber when there is no oil flow, thus always imparting elastic force to the valve core. Therefore, the responsiveness of the first valve can be improved. Furthermore, the groove formed in the vane functions as the valve body of the first valve, and the valve core of the first valve moves while contacting the bottom surface of the inclined groove, thus preventing any obstruction that would reduce the flow rate of oil through the first oil passage when the valve core receives oil pressure from the opposite direction. Therefore, the resistance of the oil acting on the vane when the valve core receives oil pressure from the opposite direction can be sufficiently reduced. Attached Figure Description

[0007] Figure 1 This is a cross-sectional view of the rotational damper involved in the embodiment.

[0008] Figure 2 This is a longitudinal sectional view of the rotary damper involved in the embodiment.

[0009] Figure 3 This is a top view of the rotor used in the embodiment.

[0010] Figure 4 This is a perspective view of the valve core used in the embodiment.

[0011] Figure 5 This is a perspective view of the valve core used in the embodiment.

[0012] Figure 6 This is a three-dimensional view of the elastomer used in the embodiment.

[0013] Figure 7 This is a diagram used to illustrate the structure and operation of the first valve used in the embodiment.

[0014] Figure 8 This is a diagram used to illustrate the structure and operation of the first valve used in the embodiment.

[0015] Figure 9 This is a diagram used to illustrate the structure and operation of the second valve used in the embodiment.

[0016] Figure 10 This is a diagram used to illustrate the structure and operation of the second valve used in the embodiment.

[0017] Explanation of reference numerals in the attached figures

[0018] 1…Housing; 2…Rotor; 3…Peripheral wall constituting the housing; 4…Bottom wall constituting the housing; 5…Cover; 6…Flange; 7…Oil chamber; 8…Blocking wall; 9…First chamber; 10…Second chamber; 11…First oil passage; 12…First valve; 13…Wall surface of the oil chamber; 14…Groove formed in the flange; 15…Valve core; 16…Side of the groove; 17…Bottom surface of the groove; 18…One side of the flange; 19…Groove formed in the valve core; 20…First corner of the valve core; 21…First side of the valve core; 22…Second side of the valve core; 23…First bottom surface of the valve core; 24…First slit ; 25…Second bottom surface of valve core; 26…Second slit; 27…Second corner of valve core; 28…Third side surface of valve core; 29…Elastomer; 30…First part of elastomer; 31…Second oil passage; 32…Second valve; 33…Valve seat; 34…Second part of elastomer; 35…Part of the first part of elastomer with an arc-shaped cross section; 36…Plate-shaped part of the first part of elastomer; 37…Other side of wing plate; 38…First slot formed in rotor; 39…Second slot formed in rotor; 40…Third slot formed in rotor. Detailed Implementation

[0019] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

[0020]

Example

[0021] First, with reference to the accompanying drawings, the construction of the rotary damper involved in the embodiment will be described.

[0022] like Figure 1 As shown, the rotary damper involved in the embodiment includes a housing 1 and a rotor 2. The housing 1 used in this embodiment has a cylindrical peripheral wall 3. (As shown...) Figure 2 As shown, one end of the peripheral wall 3 is blocked by the bottom wall 4, which is integrally formed with the peripheral wall 3. Figure 2 As shown, the other end of the peripheral wall 3 is blocked by the cap 5. (As indicated...) Figure 1 as well as Figure 2 As shown, in this embodiment, the rotor 2 is housed within the housing 1 and supported by the housing 1 and the cover 5. Figure 3 As shown, rotor 2 has wing plate 6.

[0023] like Figure 1 as well as Figure 2 As shown, the rotary damper involved in the embodiment includes an oil chamber 7. As... Figure 1 As shown, in this embodiment, the oil chamber 7 is separated by a partition wall 8 integrally formed with the peripheral wall 3 and the bottom wall 4. The oil chamber 7 is filled with oil. Figure 1 As shown, wing 6 is located in oil chamber 7. Figure 1 As shown, the oil chamber 7 is divided into two adjacent chambers separated by the wingplate 6 (hereinafter referred to as the first chamber 9 and the second chamber 10).

[0024] like Figure 1 As shown, the rotary damper involved in the embodiment includes a first valve 12 disposed in the first oil passage 11. Figure 1 as well as Figure 8 As shown, in this embodiment, the first oil passage 11 is an oil passage formed between the wing plate 6 and the wall surface 13 of the oil chamber 7 (i.e., the inner circumferential surface of the peripheral wall 3). Figure 1 , Figure 7 as well as Figure 8 As shown, the first valve 12 used in the embodiment is configured to have a groove 14 that functions as a valve body and a valve core 15.

[0025] like Figure 1 as well as Figure 3 As shown, in this embodiment, the groove 14 is formed in the wing plate 6. (As...) Figure 1 , Figure 7 as well as Figure 8 As shown, the cross-section of groove 14 is L-shaped. (As indicated...) Figure 8 As shown, the side 16 of the groove 14 has the function of preventing the valve core 15 from falling off. Figure 3 As shown, the bottom surface 17 of the groove 14 is an inclined surface. More specifically, as... Figure 7 as well as Figure 8 As shown, the bottom surface 17 of the groove 14 is inclined in such a way that the distance between one end of the bottom surface 17 (i.e., the part where one side 18 of the wing plate 6 intersects with the bottom surface 17 of the groove 14) and the wall surface 13 of the oil chamber 7 is the narrowest, and the distance between the other end of the bottom surface 17 (i.e., the part where the side surface 16 of the groove 14 intersects with the bottom surface 17 of the groove 14) and the wall surface 13 of the oil chamber 7 is the widest.

[0026] like Figure 7 as well as Figure 8 As shown, the valve core 15 used in this embodiment has a shape that allows it to move while in contact with the bottom surface 17 of the groove 14. The shape of the valve core 15 is preferably triangular prism. With the triangular prism valve core 15, when oil passes through the first oil passage 11, the oil flows along the wall 13 of the oil chamber 7, thus stabilizing the movement of the valve core 15 and enabling good control of the valve core 15. Furthermore, with the triangular prism valve core 15, since the valve core 15 does not rotate, a groove functioning as an orifice, a first slit for deforming the first bottom surface of the valve core 15, and a second slit for deforming the second bottom surface of the valve core 15 can be formed in the valve core 15. Alternatively, an orifice composed of small holes can be formed in the valve core 15 instead of a groove.

[0027] like Figure 4 As shown, the valve core 15 used in this embodiment has a groove 19 that functions as an orifice. The groove 19 is formed in the valve core 15 from one direction (in... Figure 1The corner of the valve core 15 that contacts the wall 13 of the oil chamber 7 when it receives oil pressure (in the counterclockwise direction) is referred to as the first corner 20. The first corner 20 is the corner formed by the intersection of the two sides of the valve core 15 (i.e., the first side 21 and the second side 22).

[0028] like Figure 4 as well as Figure 5 As shown, the valve core 15 used in this embodiment has a first slit 24 for deforming a first bottom surface 23 of the valve core 15 and a second slit 26 for deforming a second bottom surface 25 of the valve core 15. The first slit 24 and the second slit 26 do not contact the wall 13 of the oil chamber 7 and are formed from one direction (in... Figure 1 The corner (in the counterclockwise direction) that receives oil pressure (hereinafter referred to as the second corner 27). The second corner 27 is the corner formed by the intersection of the two sides of the valve core 15 (i.e., the second side 22 and the third side 28).

[0029] like Figure 1 As shown, the rotational damper involved in the embodiment includes an elastomer 29. For example... Figure 6 As shown, the elastic body 29 used in the embodiment is a spring having a portion that imparts elastic force to the valve core 15 of the first valve 12 (hereinafter referred to as the first part 30) and a portion that deforms toward the valve seat 33 of the second valve 32 due to the pressure of the oil in the second oil passage 31 (hereinafter referred to as the second part 34).

[0030] like Figure 6 As shown, the first portion 30 is composed of a portion 35 with an arc-shaped cross-section and a flat plate portion 36 extending from the portion 35, which always imparts an elastic force (restoring force) to the valve core 15. Therefore, when there is no oil flow, the valve core 15 (i.e., the first corner 20) contacts the wall 13 of the oil chamber 7 through the elastic force of the first portion 30. The first portion 30 is deformed by the pressure of the oil applied to the valve core 15, i.e., as... Figure 8 As shown, the flat portion 36 flexes to accumulate elastic energy, and releases this energy to return the valve core 15 to its original position, forming part of the elastic body 29. Figure 6 As shown, the second part 34 is a plate-shaped portion that intersects with the plate-shaped portion 36 of the first part 30 and is part of the elastomer 29.

[0031] like Figure 1 As shown, the rotary damper involved in the embodiment includes a second valve 32 disposed in the second oil passage 31. Figure 7 as well as Figure 8 As shown, in this embodiment, the second oil passage 31 is a passage for supplying oil to flow between one side 18 of the wingplate 6 (i.e., the first chamber 9) and the other side 37 of the wingplate 6 (i.e., the second chamber 10). Figure 3 As shown, the second oil passage 31 is formed on the rotor 2 and is configured to have a first groove 38 that opens on one side 18 of the wing plate 6 and extends from the opening to the other side 37 of the wing plate 6, a second groove 39 that opens on the other side 37 of the wing plate 6 and extends from the opening to one side 18 of the wing plate 6, and a third groove 40 that connects the first groove 38 and the second groove 39.

[0032] In this embodiment, the second valve 32 has the function of changing the flow rate of oil through the second oil passage 31 in accordance with the oil pressure. For example... Figure 9 as well as Figure 10 As shown, the second valve 32 makes the second part 34 of the elastic body 29 inserted into the second groove 39 function as a valve core, and makes the recess formed at the connection between the second groove 39 and the third groove 40 function as a valve seat 33.

[0033] Next, the operation of the first valve 12 will be explained.

[0034] Before the rotor 2 begins to rotate, i.e., when there is no oil flow, the elastic force of the first portion 30 of the elastomer 29 is applied to the valve core 15, thereby... Figure 7 As shown, the valve core 15 is in a state where the third side 28 is in contact with the bottom surface 17 of the groove 14, and the first corner 20 is in contact with the wall surface 13 of the oil chamber 7.

[0035] When rotor 2 rotates forward, valve core 15 rotates from one direction (in...) Figure 1 The middle section (counter-clockwise) receives oil pressure. For example... Figure 7 As shown, at this time, the third side 28 of the valve core 15 contacts the bottom surface 17 of the groove 14, and the first corner 20 of the valve core 15 contacts the wall surface 13 of the oil chamber 7. Therefore, most of the first oil passage 11 is blocked by the valve core 15. Thus, oil flows through the orifice formed by the groove 19 formed in the first corner 20 of the valve core 15 and the wall surface 13 of the oil chamber 7. Consequently, the oil pressure in the second chamber 10 increases, thereby increasing the resistance of the oil acting on the wing plate 6, and thus reducing the rotational speed of the rotor 2.

[0036] Normally, at high operating temperatures (70–90°C), the viscosity of the oil decreases, thus reducing the oil resistance acting on the wingplate 6. Conversely, at low operating temperatures (-40–-20°C), the viscosity of the oil increases, thus increasing the oil resistance acting on the wingplate 6. However, in this embodiment, the valve core 15 is made of resin, which expands and softens at high operating temperatures (70–90°C). At this time, oil pressure is applied to the first slit 24 and the second slit 26 of the valve core 15, thereby… Figure 5As shown, the first bottom surface 23 of the valve core 15 deforms upward (i.e., towards the cover 5) into an arc shape, and the second bottom surface 25 of the valve core 15 deforms downward (i.e., towards the bottom wall 4) into an arc shape. This narrows the gaps between the cover 5 and the valve core 15, and between the bottom wall 4 and the valve core 15. Therefore, according to the valve core 15 used in this embodiment, even if the oil viscosity decreases, the resistance of the oil acting on the wing plate 6 will not decrease. On the other hand, when the operating temperature is low (-40 to -20°C), the valve core 15 shrinks and solidifies. At this time, even if oil pressure is applied to the first slit 24 and the second slit 26 of the valve core 15, the first bottom surface 23 and the second bottom surface 25 of the valve core 15 do not deform, thereby widening the gaps between the cover 5 and the valve core 15, and between the bottom wall 4 and the valve core 15. Therefore, according to the valve core 15 used in this embodiment, even if the oil viscosity increases, the resistance of the oil acting on the wing plate 6 will not increase. As a result, the rotary damper according to the embodiments can achieve approximately the same characteristics as when used at normal temperature (15-25°C), even when used at high temperatures (70-90°C) or low temperatures (-40--20°C).

[0037] When rotor 2 reverses, valve core 15 moves from the opposite direction (in...) Figure 1 The center (clockwise) receives oil pressure. For example... Figure 8 As shown, the first portion 30 of the elastomer 29 deforms under the pressure of oil received by the valve core 15, and the valve core 15 moves towards the side 16 of the groove 14 from the side 28 of the third side surface 28 that contacts the bottom surface 17 of the groove 14. Since the bottom surface 17 of the groove 14 is inclined, the first corner 20 of the valve core 15 separates from the wall 13 of the oil chamber 7 by moving the side of the valve core 15 that contacts the bottom surface 17 of the groove 14, thereby increasing the opening area of ​​the first oil passage 11. In addition, since the valve core 15 is a triangular prism, the first side surface 21 of the valve core 15 can guide the oil in a manner that allows the oil to flow along the wall 13 of the oil chamber 7. As a result, the oil flows through the first oil passage 11 without any obstacles that reduce the flow rate of the oil, thus reducing the pressure difference between the oil in the first chamber 9 and the oil in the second chamber 10. As a result, the rotational damper according to the embodiment can sufficiently reduce the resistance of the oil acting on the wing plate 6 when the valve core 15 receives the pressure of oil from the opposite direction.

[0038] Shortly after the rotor 2 reverses direction and then rotates forward, the valve core 15 utilizes the elastic edge of the first portion 30 of the elastic body 29 to immediately move the third side 28, which is in contact with the bottom surface 17 of the groove 14, toward one end of the groove 14. This causes the first corner 20 of the valve core 15 to contact the wall 13 of the oil chamber 7. Therefore, the first valve 12 has excellent responsiveness.

[0039] Next, the operation of the second valve 32 will be explained.

[0040] When rotor 2 rotates forward, the oil in the second chamber 10 enters the second groove 39 of the second oil passage 31. At this time, when the rotational force of rotor 2 (i.e., the force that makes the rotor rotate) is relatively small, the oil pressure in the second groove 39 is lower compared to when the rotational force of rotor 2 is larger. Therefore, as Figure 9 As shown, the second part 34 of the elastic body 29, which functions as the valve core of the second valve 32, hardly deforms even when subjected to oil pressure (i.e., low pressure). The second part 34 of the elastic body 29 is elastic, therefore the degree of deformation varies correspondingly to the magnitude of the external force. In this case, the valve seat 33 of the second valve 32 (i.e., the recess formed at the connection between the second groove 39 and the third groove 40) is open, so the oil flows through the third groove 40 and the first groove 38 without flow restriction and into the first chamber 9. On the other hand, when the rotational force of the rotor 2 is large, the oil pressure in the second groove 39 is higher compared to when the rotational force of the rotor 2 is small, therefore... Figure 10 As shown, the second portion 34 of the elastomer 29 receives the pressure of the oil (i.e., higher pressure) and deforms significantly toward the valve seat 33 of the second valve 32 in a manner that blocks the valve seat 33 of the second valve 32. Therefore, the flow rate of oil flowing into the first chamber 9 through the third groove 40 and the first groove 38 is restricted. In the case of the first valve 12, the flow rate of oil restricted by the first valve 12 is constant even if the rotational force of the rotor 2 changes; however, in the case of the second valve 32, unlike the first valve 12, the flow rate of oil restricted by the second valve 32 changes with the rotational force of the rotor 2. As a result, according to the rotational damper of the embodiment, the rotational speed of the rotor 2 can be maintained at approximately constant even if the rotational force of the rotor 2 changes.

Claims

1. A rotary damper having a first valve disposed in a first oil passage, the rotary damper being characterized in that it comprises: The oil chamber is filled with oil; A winglet located in the oil chamber; The groove, which is formed in the wing plate, functions as the valve body of the first valve; The valve core of the first valve moves while its edge contacts the bottom surface of the groove; as well as An elastomer imparts elastic force to the valve core, causing the valve core to contact the wall of the oil chamber when there is no oil flow. The bottom surface of the groove is inclined, so that when the valve core receives oil pressure from one direction and is in contact with the wall of the oil chamber, it separates from the wall of the oil chamber when it receives oil pressure from the opposite direction. The valve core is triangular prism in shape. The valve core has a first slit for deforming a first bottom surface of the valve core and / or a second slit for deforming a second bottom surface of the valve core. The first slit and the second slit are formed at the corner where the two sides of the valve core intersect, that is, at the corner where they do not contact the wall of the oil chamber and receive oil pressure from one direction.

2. The rotary damper according to claim 1, characterized in that, The valve core has a groove that functions as an orifice. The groove that functions as an orifice is formed at the corner where the two sides of the valve core intersect, that is, the corner that contacts the wall of the oil chamber.

3. The rotary damper according to claim 1, characterized in that, The device further includes a second oil passage for the oil to flow between one side of the wing and the other side of the wing, and a second valve disposed in the second oil passage to reduce the amount of oil passing through the second oil passage in accordance with the oil pressure. The elastomer functions as the valve core of the second valve.

4. The rotary damper according to claim 3, characterized in that, The elastomer is a spring having a portion that imparts elastic force to the valve core of the first valve and a portion that deforms toward the valve seat of the second valve in response to the pressure of the oil in the second oil passage.

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