Reserve tank

Abstract

To provide a reserve tank that ensures ease of O-ring installation while preventing the O-ring from falling off the lid when removing the lid from the tank body. [Solution] The tank comprises a tank body 1 having a substantially cylindrical cylindrical portion 11 with an inlet formed radially inward, a lid 2 that can close the inlet by inserting a substantially cylindrical closing portion 21 into the cylindrical portion 11, and an O-ring 3 that fits into a groove 22 formed on the outer circumference of the closing portion 21. The closing portion 21 has a flange portion 23 that protrudes radially outward from the axial end side of the groove 22 in order to hold the O-ring 3, and the length of the outer circumference of the flange portion 23 is set to a length that makes it easy to assemble the O-ring 3 to the closing portion 2, and the flange portion 23 has a shape in which the distance from the central axis of the closing portion 21 to the radial outer end differs depending on the circumferential direction, and when the average value of the said distance is taken as the reference radius, it has a large diameter portion 26 in which the said distance is larger than the reference radius.

Description

Technical Field

[0004] , , ,

[0005] , , ,

[0001] The present invention relates to a reserve tank provided with an O-ring.

Background Art

[0002] Patent Document 1 discloses a reserve tank including a tank body having a cylindrical portion in which a circular inlet for injecting liquid is formed on the radially inner side, a lid having a substantially cylindrical closing portion, and an O-ring fitted into a groove formed on the outer peripheral surface of the closing portion of the lid. In this reserve tank, the inlet can be closed by inserting the closing portion of the lid into the cylindrical portion of the tank body. And by closing the lid in this way, the O-ring fitted into the groove of the closing portion of the lid seals between the closing portion of the lid and the cylindrical portion of the tank body. A flange portion that protrudes radially outward on the axially distal end side from the groove is provided on the closing portion of this lid in order to hold the O-ring in the groove.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] When a flange portion is provided on the axially distal end side of the closing portion of the lid as in the reserve tank disclosed in Patent Document 1, usually, the flange portion is formed so that the radially outer end is circular. In such a reserve tank, when fitting the O-ring into the groove during the manufacture of the reserve tank, it is necessary to temporarily stretch the O-ring so that the inner side of the O-ring can pass through the flange portion. Therefore, if the outer diameter of the flange portion is made too large, due to the characteristics of the elongation rate of the O-ring, it becomes difficult to assemble the O-ring. In order to prevent such a problem, the outer diameter of the flange portion is set to a size that is easy to assemble the O-ring.

[0005] However, because the outer diameter of the flange is set to a size that makes it easy to assemble the O-ring, when removing the lid from the tank body for inspection or maintenance, the flange may pass through the inside of the O-ring, causing the O-ring to fall off the lid.

[0006] Therefore, the present invention aims to provide a reserve tank that ensures ease of assembly of the O-ring while preventing the O-ring from falling off the lid when the lid is removed from the tank body. [Means for solving the problem]

[0007] The reserve tank according to the present invention comprises a tank body having a substantially cylindrical cylindrical portion having a circular inlet formed radially inward for pouring liquid, a lid having a substantially cylindrical closing portion which can close the inlet by inserting the closing portion into the cylindrical portion, and an O-ring fitted into a groove formed on the outer circumferential surface of the closing portion which seals the space between the closing portion and the cylindrical portion when the closing portion is inserted into the cylindrical portion, wherein the closing portion has a flange portion that protrudes radially outward from the bottom surface of the groove at the axial end side of the groove in order to hold the O-ring, the length of the outer circumference of the flange portion is set to a length that makes it easy to assemble the O-ring to the closing portion, the flange portion has a shape in which the distance from the central axis of the closing portion to the radial outer end differs depending on the circumferential direction, and the flange portion has a large diameter portion in which the distance is greater than the reference radius when the average value of the distance is taken as the reference radius. [Effects of the Invention]

[0008] The present invention provides a reserve tank that ensures ease of O-ring assembly while preventing the O-ring from falling off the lid when the lid is removed from the tank body. [Brief explanation of the drawing]

[0009] [Figure 1]This is a cross-sectional view showing the shape of the cylindrical part of the tank body and the closing part of the lid of the reserve tank according to the first embodiment. [Figure 2] This figure shows the shape of the flange portion of the lid of the reserve tank in the first embodiment. [Figure 3] This figure shows the shape of the flange portion of the lid of the reserve tank in the second embodiment. [Figure 4] This figure shows the shape of the flange portion of the lid of the reserve tank in the third embodiment. [Figure 5] This figure shows the shape of the flange portion of the lid of the reserve tank in the fourth embodiment. [Figure 6] This figure shows the shape of the flange portion of the lid of the reserve tank according to the fifth embodiment. [Modes for carrying out the invention]

[0010] <First Embodiment> The reserve tank 10 of the first embodiment will be described below with reference to Figures 1 and 2. Figure 1 is a cross-sectional view showing the shape of the cylindrical portion 11 of the tank body 1 and the closing portion 21 of the lid 2 of the reserve tank 10. As shown in Figure 1, the reserve tank 10 comprises a tank body 1 having a substantially cylindrical cylindrical portion 11 with a circular inlet formed radially inward for liquid injection, a lid 2 having a substantially cylindrical closing portion 21, and an O-ring 3.

[0011] A groove 22 is formed on the outer circumferential surface of the closing portion 21 of the lid 2, recessing radially inward. The closing portion 21 of the lid 2 has a flange portion 23 that protrudes radially outward from the bottom surface 22a of the groove 22, axially towards the tip of the groove 22, in order to hold the O-ring 3 in the groove 22. A tapered surface 24 is formed on the axial tip side of the flange portion 23, with its outer diameter decreasing in a conical shape toward the axial tip. Furthermore, a plane 25 perpendicular to the central axis of the closing portion 21 is formed at the axial tip of the closing portion 21 of the lid 2.

[0012] The O-ring 3 is fitted into the groove 22. The lid 2 can close the inlet by inserting the closing portion 21 into the cylindrical portion 11 of the tank body 1. When the lid 2 is closed in this way and the closing portion 21 of the lid 2 is inserted into the cylindrical portion 11 of the tank body 1, the O-ring 3 deforms by being compressed radially against the closing portion 21, thereby sealing the space between the closing portion 21 and the cylindrical portion 11.

[0013] When assembling the O-ring 3 to the closing portion 21 of the lid 2 during the manufacturing of the reserve tank 10, the O-ring 3 is brought into contact with the tapered surface 24 of the closing portion 21 of the lid 2 and pushed axially toward the groove 22. As a result, the O-ring 3 stretches to a length greater than the outer circumference of the flange portion 23, and the O-ring 3 goes beyond the flange portion 23 into the groove 22. Once inside the groove 22, the O-ring 3 shrinks back to its normal length and comes into contact with the bottom surface 22a of the groove 22. When the O-ring 3 is fitted into the groove 22 in this way, the flange portion 23 holds the O-ring 3 in place so that it does not fall out even when gravity is applied downward as shown in Figure 1.

[0014] Figure 2 shows the shape of the flange portion 23 of the lid 2 of the reserve tank 10. Figure 2 shows the lid 2 with the O-ring 3 assembled to the closing portion 21, viewed from below in Figure 1. As shown in Figure 2, the outer circumference of the flange portion 23 is composed of a gentle curve, and the length of the outer circumference of the flange portion 23 is set to a length that makes it easy to assemble the O-ring 3 to the closing portion 21 of the lid 2. Therefore, the reserve tank 10 ensures that the O-ring 3 is easy to assemble.

[0015] Furthermore, the flange portion 23 has a shape in which the distance from the central axis of the closing portion 21 to its radially outer end differs depending on the circumferential direction. If the average value of the distance from the central axis of the closing portion 21 to its radially outer end is taken as the reference radius, the flange portion 23 has three large-diameter portions 26 in which the distance from the central axis of the closing portion 21 to its radially outer end is greater than the reference radius. Because the flange portion 23 has these three large-diameter portions 26, the reserve tank 10 can prevent the O-ring 3 from falling off the lid 2 when the lid 2 is removed from the tank body 1.

[0016] <Second Embodiment> Next, referring to FIG. 3, the reserve tank 20 of the second embodiment will be described. The reserve tank 20 has the same configuration as the reserve tank 10 of the first embodiment, except that the shape of the flange portion 23a of the lid 2a is different. Therefore, the shape of the flange portion 23a of the lid 2a will be described below, and the same reference numerals will be given to the parts common to the reserve tank 10 of the first embodiment, and the description thereof will be omitted.

[0017] FIG. 3 is a view showing the shape of the flange portion 23a of the lid 2a of the reserve tank 20. FIG. 3 shows a state in which the O-ring 3 is assembled to the closing portion 21a of the lid 2a. As shown in FIG. 3, the outer periphery of the flange portion 23a is formed by a gentle curve, and the length of the outer periphery of the flange portion 23a is set to a length that is easy to assemble when the O-ring 3 is assembled to the closing portion 21a of the lid 2a. Therefore, the reserve tank 20 ensures easy assembly of the O-ring 3.

[0018] Furthermore, the flange portion 23a has a shape in which the distance from the central axis of the closing portion 21a to the radially outer end varies in the circumferential direction. And when the average value of the distance from the central axis of the closing portion 21a to the radially outer end of the flange portion 23a is used as the reference radius, the flange portion 23a has four large-diameter portions 26a where the distance from the central axis of the closing portion 21a to the radially outer end is larger than the reference radius. Since the flange portion 23a has four large-diameter portions 26a in this way, the reserve tank 20 can suppress the O-ring 3 from falling off the lid 2a when the lid 2a is removed from the tank body 1.

[0019] <Third Embodiment> Next, referring to FIG. 4, the reserve tank 30 of the third embodiment will be described. The reserve tank 30 has the same configuration as the reserve tank 10 of the first embodiment, except that the shape of the flange portion 23b of the lid 2b is different. Therefore, the shape of the flange portion 23b of the lid 2b will be described below, and the same reference numerals will be given to the parts common to the reserve tank 10 of the first embodiment, and the description thereof will be omitted.

[0020] FIG. 4 is a view showing the shape of the flange portion 23b of the lid 2b of the reserve tank 30. FIG. 4 shows a state where the O-ring 3 is assembled to the closing portion 21b of the lid 2b. As shown in FIG. 4, the outer periphery of the flange portion 23b is formed of a gentle curve, and the length of the outer periphery of the flange portion 23b is set to a length that is easy to assemble when the O-ring 3 is assembled to the closing portion 21b of the lid 2b. Therefore, the reserve tank 30 ensures easy assembly of the O-ring 3.

[0021] Furthermore, the flange portion 23b has a shape in which the distance from the central axis of the closing portion 21b to the radially outer end varies depending on the circumferential direction. And when the average value of the distance from the central axis of the closing portion 21b to the radially outer end of the flange portion 23b is used as the reference radius, the flange portion 23b has a large-diameter portion 26b at one location where the distance from the central axis of the closing portion 21b to the radially outer end is larger than the reference radius. Since the flange portion 23b has one large-diameter portion 26b in this way, the reserve tank 30 can suppress the O-ring 3 from falling off the lid 2b when the lid 2b is removed from the tank body 1.

[0022] <Fourth Embodiment> Next, the reserve tank 40 of the fourth embodiment will be described with reference to FIG. 5. The reserve tank 40 has the same configuration as the reserve tank 10 of the first embodiment, except that the shape of the flange portion 23c of the lid 2c is different. Therefore, the shape of the flange portion 23c of the lid 2c will be described below, and the same reference numerals will be given to the parts common to the reserve tank 10 of the first embodiment and the description thereof will be omitted.

[0023] FIG. 5 is a view showing the shape of the flange portion 23c of the lid 2c of the reserve tank 40. FIG. 5 shows a state where the O-ring 3 is assembled to the closing portion 21c of the lid 2c. As shown in FIG. 5, the outer periphery of the flange portion 23c is formed of a gentle curve, and the length of the outer periphery of the flange portion 23c is set to a length that is easy to assemble when the O-ring 3 is assembled to the closing portion 21c of the lid 2c. Therefore, the reserve tank 40 ensures easy assembly of the O-ring 3.

[0024] Furthermore, the flange portion 23c has a shape in which the distance from the central axis of the closing portion 21c to its radially outer end differs depending on the circumferential direction. If the average value of the distance from the central axis of the closing portion 21c to the radially outer end of the flange portion 23c is taken as the reference radius, the flange portion 23c has three large-diameter arc-shaped portions 26c where the distance from the central axis of the closing portion 21c to its radially outer end is greater than the reference radius. Because the flange portion 23c has these three large-diameter portions 26c, the reserve tank 40 can prevent the O-ring 3 from falling off the lid 2c when the lid 2c is removed from the tank body 1.

[0025] <Fifth Embodiment> Next, the reserve tank 50 of the fifth embodiment will be described with reference to Figure 6. The reserve tank 50 has the same configuration as the reserve tank 10 of the first embodiment, except that the shape of the flange portion 23d of the lid 2d is different. Therefore, the shape of the flange portion 23d of the lid 2d will be described below, and parts common to the reserve tank 10 of the first embodiment will be given the same reference numerals and their descriptions will be omitted.

[0026] Figure 6 shows the shape of the flange portion 23d of the lid 2d of the reserve tank 50. Figure 6 shows the state in which the O-ring 3 is assembled to the closing portion 21d of the lid 2d. As shown in Figure 6, the outer circumference of the flange portion 23d is composed of a gentle curve, and the length of the outer circumference of the flange portion 23d is set to a length that makes it easy to assemble the O-ring 3 to the closing portion 21d of the lid 2d. Therefore, the reserve tank 50 ensures that the O-ring 3 is easy to assemble.

[0027] Furthermore, the flange portion 23d has a shape in which the distance from the central axis of the closing portion 21d to its radially outer end differs depending on the circumferential direction. If the average value of the distance from the central axis of the closing portion 21d to the radially outer end of the flange portion 23d is taken as the reference radius, the flange portion 23d has one large-diameter arc-shaped portion 26d where the distance from the central axis of the closing portion 21d to its radially outer end is greater than the reference radius. Because the flange portion 23d has one large-diameter portion 26d in this way, the reserve tank 50 can prevent the O-ring 3 from falling off the lid 2d when the lid 2d is removed from the tank body 1.

[0028] <Supplement to the embodiment> The reserve tank of this disclosure is not limited to the above-described form and can be implemented in various forms within the scope of the gist of this disclosure. For example, the flange portion may be provided with five or more large-diameter sections. [Explanation of symbols]

[0029] 1 Tank body, 2, 2a, 2b, 2c, 2d Lid, 3 O-ring, 10, 20, 30, 40, 50 Reserve tank, 11 Cylindrical section, 21, 21a, 21b, 21c, 21d Closure section, 22 Groove, 22a Bottom surface, 23, 23a, 23b, 23c, 23d Flange section, 24 Tapered surface, 25 Flat surface, 26, 26a, 26b, 26c, 26d Large diameter section.

Claims

[Claim 1] A tank body having a roughly cylindrical section with a circular inlet formed radially inward for pouring liquid, A lid having a substantially cylindrical closing portion, the inlet can be closed by inserting the closing portion into the cylindrical portion, An O-ring is fitted into a groove formed on the outer circumferential surface of the closing portion, and seals the space between the closing portion and the cylindrical portion when the closing portion is inserted into the cylindrical portion. A reserve tank equipped with, The closing portion has a flange portion that protrudes radially outward from the bottom surface of the groove on the axial tip side of the groove in order to hold the O-ring, The length of the outer circumference of the flange portion is set to a length that makes it easy to assemble the O-ring to the closing portion. The flange portion has a shape in which the distance from the central axis of the closing portion to the radial outer end differs depending on the circumferential direction, and the reserve tank is characterized in that it has a large-diameter portion in which the distance is greater than the reference radius when the average value of the distance is taken as the reference radius.

Images