Rotary damper

Abstract

The present invention can improve the responsiveness of a valve and sufficiently reduce the resistance of oil acting on a wing plate when a valve body receives the pressure of oil from the opposite direction. The present invention provides a rotary damper having a first valve (12) provided in a first oil passage (11), the rotary damper being provided with: an oil chamber (7) filled with oil; a wing plate (6) located in the oil chamber (7); a groove (14) formed in the wing plate (6) and functioning as a valve body of the first valve (12); a valve body (15) of a first valve (12) that moves while in contact with the bottom surface (17) of the groove (14); and an elastic body (29) that applies an elastic force to the valve body (15) and causes the valve body (15) to come into contact with the wall surface (13) of the oil chamber (7) when no oil flows, and the bottom surface (17) of the groove (14) is an inclined surface, whereby the valve body (15), which comes into contact with the wall surface (13) of the oil chamber (7) when the oil pressure is received from one direction, is separated from the wall surface (13) of the oil chamber (7) when the oil pressure is received from the opposite direction.

Description

[0001] This application is a divisional application of the invention patent application with patent application number 202110049509.5 (application date: January 14, 2021, invention name: "Rotary Damper"). Technical Field

[0002] The present invention relates to a rotary damper having a valve provided in an oil passage. Background Art

[0003] Patent Document 1 below discloses a rotary damper with a valve located in an oil passage. This rotary damper comprises an oil chamber filled with oil, a vane located within the oil chamber, a groove formed in the vane that functions as the oil passage, a valve core that moves while in contact with the end surface of the vane, and an elastic body that applies a spring force to the valve core, forcing it into contact with one surface of the vane when oil is not flowing. The valve core contacts one surface of the vane when receiving oil pressure from one direction and separates from the one surface of the vane when receiving oil pressure from the opposite direction. This rotary damper improves valve responsiveness by applying the elastic force of the elastic body to the valve core. However, this rotary damper is constructed so that the groove formed in the vane functions as the oil passage. The valve core, which blocks the groove, separates from the one surface of the vane when receiving oil pressure from the opposite direction. The elastic body deforms when the valve core separates from the one surface of the vane, but there is a limit to how much it can deform, resulting in a narrow gap between the valve core and the one surface of the vane. Therefore, the flow rate of oil passing through the groove is limited by the narrow gap. Therefore, in this rotary damper, the oil resistance acting on the vane plate when the valve element receives oil pressure from the reverse direction cannot be sufficiently reduced.

[0004] Patent Document 1: Japanese Patent Application Laid-Open No. 2000-120747 Summary of the Invention

[0005] The present invention has been made in view of the above-mentioned situation, and an object thereof is to improve valve responsiveness and to sufficiently reduce the oil resistance acting on the vane when the valve element receives oil pressure from the reverse direction.

[0006] and a tube connecting the dischar e side of the pump with a plug in the forward end of the crank case, said tube having a check valve in it at the pump end, and said former tube which connects the pump to the oil drain plug, said tube having a check valve in it at the pump end, and said former tube which connects the pump to the oil drain plug, and said former tube which connects the pump to the oil drain plug.

[0007] The rotary damper according to the present invention includes an elastic body that imparts a spring force to the valve core and, when oil is not flowing, keeps the valve core in contact with the wall of the oil chamber. This ensures that the spring force of the elastic body is always applied to the valve core. This improves the responsiveness of the first valve. Furthermore, the groove formed in the vane plate functions as the valve body of the first valve. The valve core of the first valve moves while in contact with the bottom surface of the inclined groove. This prevents the valve core from receiving oil pressure from the opposite direction, thereby preventing the flow of oil through the first oil passage from being obstructed. Consequently, the oil resistance acting on the vane plate when the valve core receives oil pressure from the opposite direction can be substantially reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 It is a transverse cross-sectional view of the rotary damper according to the embodiment.

[0009] Figure 2 It is a longitudinal sectional view of the rotary damper according to the embodiment.

[0010] Figure 3 FIG. 4 is a top view of a rotor used in the embodiment.

[0011] Figure 4 3D is a perspective view of the valve core used in the embodiment.

[0012] Figure 5 3D is a perspective view of the valve core used in the embodiment.

[0013] Figure 6 is a perspective view of the elastic body used in the embodiment.

[0014] Figure 7 This is a diagram for explaining the structure and operation of the first valve used in the embodiment.

[0015] Figure 8 This is a diagram for explaining the structure and operation of the first valve used in the embodiment.

[0016] Figure 9This is a diagram for explaining the structure and operation of the second valve used in the embodiment.

[0017] Figure 10 This is a diagram for explaining the structure and operation of the second valve used in the embodiment.

[0018] Description of Reference Numerals

[0019] 1…housing; 2…rotor; 3…circumferential wall constituting the housing; 4…bottom wall constituting the housing; 5…cover; 6…wing plate; 7…oil chamber; 8…partition 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 wing plate; 15…valve core; 16…side surface of the groove; 17…bottom surface of the groove; 18…one surface of the wing plate; 19…groove formed in the valve core; 20…first corner portion of the valve core; 21…first side surface of the valve core; 22…second side surface of the valve core; 23…first bottom surface of the valve core; 24…first slit ; 25…the second bottom surface of the valve core; 26…the second slit; 27…the second corner of the valve core; 28…the third side surface of the valve core; 29…the elastomer; 30…the first part of the elastomer; 31…the second oil passage; 32…the second valve; 33…the valve seat; 34…the second part of the elastomer; 35…the portion with an arc-shaped cross-section constituting the first part of the elastomer; 36…the flat-plate-shaped portion constituting the first part of the elastomer; 37…the other surface of the wing plate; 38…the first groove formed in the rotor; 39…the second groove formed in the rotor; 40…the third groove formed in the rotor. DETAILED DESCRIPTION

[0020] Hereinafter, embodiments of the present invention will be described based on the examples shown in the accompanying drawings.

[0021] [Example]

[0022] First, the structure of a rotary damper according to an embodiment will be described with reference to the drawings.

[0023] like Figure 1 As shown in FIG. 1 , the rotary damper according to the embodiment includes a housing 1 and a rotor 2. The housing 1 used in the embodiment has a cylindrical peripheral wall 3. Figure 2 As shown, one end of the peripheral wall 3 is blocked by the bottom wall 4 formed integrally with the peripheral wall 3. Figure 2 As shown, the other end of the peripheral wall 3 is blocked by the cover 5. Figure 1 as well as Figure 2 As shown in FIG. 1 , the rotor 2 used in the embodiment is housed in the housing 1 and supported by the housing 1 and the cover 5. Figure 3 As shown, the rotor 2 has vanes 6 .

[0024] like Figure 1 as well as Figure 2As shown in FIG. 1 , the rotary damper according to the embodiment includes an oil chamber 7. Figure 1 As shown, the oil chamber 7 used in the embodiment is divided 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, the wing plate 6 is located in the oil chamber 7. Figure 1 As shown, the oil chamber 7 is divided into two chambers (hereinafter referred to as a first chamber 9 and a second chamber 10 ) adjacent to each other via the vane 6 .

[0025] like Figure 1 As shown in FIG. 1 , the rotary damper according to the embodiment includes a first valve 12 provided in the first oil passage 11. Figure 1 as well as Figure 8 As shown, the first oil passage 11 used in the embodiment is an oil passage formed between the wing plate 6 and the wall surface 13 of the oil chamber 7 (ie, the inner peripheral 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 include a groove 14 and a valve element 15 that function as a valve body of the first valve 12 .

[0026] like Figure 1 as well as Figure 3 As shown in FIG. 1 , the groove 14 used in the embodiment is formed in the wing plate 6. Figure 1 、 Figure 7 as well as Figure 8 As shown, the cross section of the groove 14 is L-shaped. Figure 8 As shown, the side surface 16 of the groove 14 has the function of preventing the valve core 15 from falling off. Figure 3 As shown in FIG, the bottom surface 17 of the groove 14 is an inclined surface. Figure 7 as well as Figure 8 As shown, the bottom surface 17 of the groove 14 is an inclined surface in such a manner that the distance between one end of the bottom surface 17 (i.e., the portion where one surface 18 of the wing plate 6 intersects the bottom surface 17 of the groove 14) and the wall surface 13 of the oil chamber 7 is narrowest, and the distance between the other end of the bottom surface 17 (i.e., the portion where the side surface 16 of the groove 14 intersects the bottom surface 17 of the groove 14) and the wall surface 13 of the oil chamber 7 is widest.

[0027] like Figure 7 as well as Figure 8As shown, the valve core 15 used in the embodiment has a shape that can move while in contact with the bottom surface 17 of the groove 14. The shape of the valve core 15 is preferably a triangular prism. According to the triangular prism valve core 15, when the oil passes through the first oil path 11, the oil flows along the wall surface 13 of the oil chamber 7, so the movement of the valve core 15 is stable, so that the valve core 15 can be well controlled. In addition, according to the triangular prism valve core 15, since the valve core 15 does not rotate, it is possible to form a groove that functions as a hole, 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 on the valve core 15. In addition, instead of the groove, a hole consisting of a small hole can be formed on the valve core 15.

[0028] like Figure 4 As shown, the valve core 15 used in the embodiment has a groove 19 that functions as an eyelet. The groove 19 is formed in the valve core 15 from one direction (in Figure 1 The corner portion of the valve core 15 (hereinafter referred to as the first corner portion 20) contacts the wall surface 13 of the oil chamber 7 when receiving oil pressure (in the counterclockwise direction). The first corner portion 20 is the corner formed by the intersection of the two side surfaces of the valve core 15 (i.e., the first side surface 21 and the second side surface 22).

[0029] like Figure 4 as well as Figure 5 As shown, the valve core 15 used in the embodiment has a first slit 24 for deforming the first bottom surface 23 of the valve core 15 and a second slit 26 for deforming the second bottom surface 25 of the valve core 15. The first slit 24 and the second slit 26 do not contact the wall surface 13 of the oil chamber 7 and are formed in one direction (in Figure 1 The second corner 27 is a corner formed by the intersection of two side surfaces of the valve core 15 (ie, the second side surface 22 and the third side surface 28).

[0030] like Figure 1 As shown in FIG. 1 , the rotary damper according to the embodiment includes an elastic body 29. Figure 6 As shown, the elastomer 29 used in the embodiment is a spring having a portion (hereinafter referred to as the first portion 30) that imparts elastic force to the valve core 15 of the first valve 12 and a portion (hereinafter referred to as the second portion 34) that receives the pressure of the oil in the second oil circuit 31 and deforms toward the valve seat 33 of the second valve 32.

[0031] like Figure 6As shown in FIG. 1 , the first portion 30 is composed of a portion 35 having an arc-shaped cross section and a flat portion 36 extending from the portion 35, and constantly applies 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 portion 20) contacts the wall 13 of the oil chamber 7 due to the elastic force of the first portion 30. The first portion 30 is deformed by the oil pressure applied via the valve core 15, i.e., Figure 8 As shown, the flat plate portion 36 is bent to store elastic energy, and is a part of the elastic body 29 that returns the valve element 15 to its original position by releasing the energy. Figure 6 As shown, the second portion 34 is a flat plate-shaped portion that intersects the flat plate-shaped portion 36 of the first portion 30 and is a portion of the elastic body 29 .

[0032] like Figure 1 As shown, the rotary damper according to the embodiment includes a second valve 32 provided in the second oil passage 31. Figure 7 as well as Figure 8 As shown, the second oil passage 31 used in the embodiment is a passage for supplying oil between one surface 18 side of the wing plate 6 (i.e., the first chamber 9) and the other surface 37 side of the wing plate 6 (i.e., the second chamber 10). Figure 3 As shown, the second oil passage 31 is formed in the rotor 2 and is configured to include a first groove 38 that opens on the one surface 18 side of the vane 6 and extends from the opening to the other surface 37 side of the vane 6, a second groove 39 that opens on the other surface 37 side of the vane 6 and extends from the opening to the one surface 18 side of the vane 6, and a third groove 40 that connects the first groove 38 and the second groove 39.

[0033] The second valve 32 used in the embodiment has a function of changing the flow rate of the oil passing through the second oil passage 31 in accordance with the pressure of the oil. Figure 9 as well as Figure 10 As shown, the second valve 32 uses the second portion 34 of the elastic body 29 inserted into the second groove 39 to function as a valve element, and uses the recess formed at the connection between the second groove 39 and the third groove 40 to function as a valve seat 33 .

[0034] Next, the operation of the first valve 12 will be described.

[0035] Before the rotor 2 starts to rotate, that is, when there is no oil flow, the elastic force of the first portion 30 of the elastic body 29 is applied to the valve core 15, thereby Figure 7 As shown, the valve element 15 is in a state where the third side surface 28 contacts the bottom surface 17 of the groove 14 and the first corner portion 20 contacts the wall surface 13 of the oil chamber 7 .

[0036] When the rotor 2 rotates forward, the valve core 15 moves from one direction (in Figure 1 (counterclockwise in the middle) to receive the oil pressure. Figure 7 As shown, at this point, the third side surface 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 13 of the oil chamber 7. As a result, the valve core 15 blocks most of the first oil passage 11. Consequently, oil flows through the aperture formed by the groove 19 formed in the first corner 20 of the valve core 15 and the wall 13 of the oil chamber 7. This increases the oil pressure in the second chamber 10, increasing the oil resistance acting on the vane 6 and thus reducing the rotational speed of the rotor 2.

[0037] Generally, when the operating temperature is high (70 to 90°C), the viscosity of the oil decreases, so the resistance of the oil acting on the vane 6 becomes smaller. In addition, when the operating temperature is low (-40 to -20°C), the viscosity of the oil increases, so the resistance of the oil acting on the vane 6 becomes larger. However, the valve core 15 used in the embodiment is made of resin, and when the operating temperature is high (70 to 90°C), the valve core 15 expands and softens. At this time, oil pressure is applied to the first slit 24 and the second slit 26 of the valve core 15, thereby Figure 5 As shown, the first bottom surface 23 of the valve core 15 deforms upward (i.e., toward the cover 5) into an arched shape, while the second bottom surface 25 of the valve core 15 deforms downward (i.e., toward the bottom wall 4). This narrows the gap between the cover 5 and the valve core 15, and the gap between the bottom wall 4 and the valve core 15. Therefore, with the valve core 15 used in this embodiment, even if the oil viscosity decreases, the oil resistance acting on the vane 6 does not decrease. On the other hand, at low operating temperatures (-40 to -20°C), the valve core 15 shrinks and solidifies. In this case, even if oil pressure is applied to the first and second slits 24 and 26 of the valve core 15, the first and second bottom surfaces 23 and 25 of the valve core 15 do not deform, and the gap between the cover 5 and the valve core 15, and the gap between the bottom wall 4 and the valve core 15, widen. Therefore, with the valve core 15 used in this embodiment, even if the oil viscosity increases, the oil resistance acting on the vane 6 does not increase. As a result, the rotary damper according to the embodiment can obtain characteristics substantially the same as those when used at room temperature (15 to 25°C) even when used at high temperature (70 to 90°C) or low temperature (-40 to -20°C).

[0038] When the rotor 2 is reversed, the valve core 15 moves from the opposite direction (in Figure 1 (clockwise in the middle) to receive the oil pressure. Figure 8As shown, the first portion 30 of the elastic body 29 deforms under the pressure of the oil received by the valve core 15, causing the valve core 15 to move toward the side surface 16 of the groove 14 while its third side surface 28 contacts the bottom surface 17 of the groove 14. Because 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 as the valve core 15 moves while in contact with the bottom surface 17 of the groove 14, thereby increasing the opening area of ​​the first oil passage 11. Furthermore, because the valve core 15 is a triangular prism, the first side surface 21 of the valve core 15 guides the oil along the wall 13 of the oil chamber 7. This allows the oil to flow through the first oil passage 11, free of obstacles that could reduce the oil flow rate, thereby reducing the pressure difference between the oil in the first chamber 9 and the oil in the second chamber 10. As a result, the rotary damper according to this embodiment can significantly reduce the oil resistance acting on the vane 6 when the valve core 15 receives oil pressure from the opposite direction.

[0039] When the rotor 2 rotates forward shortly after reverse rotation, the valve element 15 immediately moves toward one end of the groove 14 while the third side surface 28 contacts the bottom surface 17 of the groove 14 due to the elastic force of the first portion 30 of the elastic body 29. As a result, the first corner portion 20 of the valve element 15 contacts the wall surface 13 of the oil chamber 7. Therefore, the responsiveness of the first valve 12 is very good.

[0040] Next, the operation of the second valve 32 will be described.

[0041] When the 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 the rotor 2 (i.e., the force that rotates the rotor) is small, the pressure of the oil in the second groove 39 is lower than when the rotational force of the rotor 2 is large. Figure 9 As shown, the second portion 34 of the elastomer 29 that functions as the valve core of the second valve 32 hardly deforms even when it receives oil pressure (i.e., low pressure). The second portion 34 of the elastomer 29 has elasticity, so the degree of deformation changes corresponding to the magnitude of the external force. In this case, the valve seat 33 of the second valve 32 (i.e., the depression formed at the connection between the second groove 39 and the third groove 40) is open, so the oil passes through the third groove 40 and the first groove 38 without flow restriction and flows into the first chamber 9. On the other hand, when the rotational force of the rotor 2 is large, the pressure of the oil in the second groove 39 is higher than when the rotational force of the rotor 2 is small, so as Figure 10As shown, the second portion 34 of the elastic body 29 receives the pressure of the oil (i.e., a relatively high pressure) and deforms significantly toward the valve seat 33 of the second valve 32, thereby blocking 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 remains 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 as the rotational force of the rotor 2 changes. As a result, according to the rotary damper involved in the embodiment, the rotational speed of the rotor 2 can be maintained at a substantially constant level even if the rotational force of the rotor 2 changes.

Claims

1. A rotary damper having a first valve provided in a first oil passage, wherein the rotary damper is characterized by comprising: an oil chamber filled with oil; a wing plate located in the oil chamber; a groove formed in the wing plate and functioning as a valve body of the first valve; The valve core of the first valve moves while in contact with the bottom surface of the groove; as well as an elastic body that applies elastic force to the valve element so as to bring the valve element into contact with the wall surface of the oil chamber when the oil does not flow; The bottom surface of the groove is an inclined surface, whereby the valve element, which contacts the wall surface of the oil chamber when receiving the oil pressure from one direction, separates from the wall surface of the oil chamber when receiving the oil pressure from the opposite direction. The invention further comprises a second oil passage for circulating the oil between one surface side of the wing plate and the other surface side of the wing plate, and a second valve provided in the second oil passage for reducing the amount of the oil passing through the second oil passage in accordance with the pressure of the oil. The elastic body functions as a valve element of the second valve.

2. The rotary damper according to claim 1, characterized in that The valve core is in the shape of a triangular prism.

3. The rotary damper according to claim 1, characterized in that The shape of the valve core is a triangular prism. The valve element includes a groove functioning as an eyelet, and the groove functioning as the eyelet is formed at a corner where two side surfaces of the valve element intersect, that is, at a corner contacting a wall surface of the oil chamber.

4. The rotary damper according to claim 1, characterized in that The shape of the valve core is a triangular prism. The valve core has a first slit for deforming the first bottom surface of the valve core and / or a second slit for deforming the second bottom surface of the valve core. The first slit and the second slit are formed at a corner formed by the intersection of two side surfaces of the valve core, that is, a corner that does not contact the wall of the oil chamber and receives oil pressure from one direction.

5. The rotary damper according to claim 1, characterized in that The elastic body is a spring having a portion that applies elastic force to the valve element of the first valve and a portion that receives the pressure of the oil in the second oil passage and deforms toward the valve seat of the second valve.

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