JP5493559B2 - Reservoir tank - Google Patents

Description

  The present invention relates to a reservoir tank applied to, for example, a hydraulic power steering apparatus.

  Conventionally, as a reservoir tank, what was described, for example in patent documents 1 is known. This reservoir tank is formed by attaching a cap to an oil filling port formed in the upper part of a tank body that stores hydraulic oil. The cap is made up of a resin cap body and a rubber seal cap, thereby forming an air chamber communicating with the inside of the tank body between the cap body and the seal cap, and the air chamber is connected to the outside air. It forms a labyrinth that communicates with the labyrinth. That is, this labyrinth structure is formed by pressing a plurality of protrusions having a mountain-shaped cross section projecting concentrically on the upper surface of the flange portion of the seal cap against the opposing surface of the cap body. The air chamber communicates with the outside air through a notch formed at a predetermined angular position of each protrusion. According to this maze structure, the pressure inside the tank main body is kept constant by communicating the inside of the tank main body with the outside air through the air chamber, and the tank bounces back due to, for example, vibration during running of the vehicle. The hydraulic oil inside the main body is prevented from leaking outside. In particular, the concave portion is provided between the protrusions of the seal cap so that the flange portion can be easily bent, so that the cap can be easily opened and closed without deteriorating the sealing performance.

Japanese Utility Model Publication No. 2-49177

By the way, as in the reservoir tank of Patent Document 1, it has been confirmed that the suppression of hydraulic fluid leakage by the maze structure cannot obtain a sufficient effect when the vibration of the vehicle or the like is large.
The objective of this invention is providing the reservoir tank which can suppress more reliably the leakage to the exterior of the hydraulic oil accompanying a vibration etc.

In order to solve the above-mentioned problems, the invention according to claim 1 includes a tank main body in which an oil filling port is formed at an upper portion and storing hydraulic oil, and a cap that is attached to the oil filling port and closes the oil filling port. In the reservoir tank provided, the cap includes a cylindrical body having an internal space extending in a vertical direction, a vent hole communicating the interior of the tank body and the internal space at a lower portion of the cylindrical body, and the cylindrical body A vent means for communicating the internal space and the outside air, and is slidably accommodated in the internal space in the vertical direction, and communicates the vent hole and the vent means with a gap between the cylinder body. A movable body that is mounted on the movable body and accommodated in the internal space, and has an outer diameter that is smaller than the inner diameter of the cylindrical body in a free state, thereby providing a gap between the cylindrical body and the movable body. Open the vent Communicating fine said vent means, when Ru is compressed by movable body during upward movement of the movable body, by diameter to the same outer diameter as the inner diameter of at least the cylindrical body, a clearance of the cylindrical body and the movable body And a sealing member that is elastically deformed so as to be closed.

  According to this configuration, in the free state of the seal member, the seal member opens a gap between the cylindrical body and the movable body so that the vent hole and the vent means communicate. Accordingly, when the elastic deformation of the seal member is little or not, for example, when vibration is small, the gap between the cylindrical body and the movable body is opened by the seal member so that the vent hole and the vent means communicate with each other. Is done. Thereby, the air pressure inside the tank body can be kept constant by communicating the inside of the tank body with the outside air. On the other hand, when the movable body moves up significantly, for example, when vibration is large, the gap between the cylindrical body and the movable body is closed by the seal member that is compressed and elastically deformed by the movable body. Therefore, it is possible to suppress the hydraulic oil inside the tank body that has been bounced back by vibration or the like from leaking outside through the gap between the cylindrical body and the movable body.

  According to a second aspect of the present invention, in the reservoir tank according to the first aspect, the cap is oil-tightly attached to the oil supply port to close the oil supply port, and an upper side of the cap body is provided. A gist is provided that the ventilation means is a labyrinth formed between the cap body and the cap cover on the outer peripheral side of the cylindrical body.

  According to this configuration, the ventilation means is a labyrinth formed between the cap body and the cap cover, and the amount of the hydraulic oil inside the tank body is reduced by the complexity of the ventilation flow path. Leakage to the outside through the ventilation means can be suppressed.

  According to a third aspect of the present invention, in the reservoir tank according to the first or second aspect, the movable body is placed on the seal member and slidably accommodated in the internal space together with the seal member. In summary, the seal member includes a weight body that is elastically deformed so as to close a gap between the cylindrical body and the movable body.

  According to this configuration, the seal member is elastically deformed so as to close the gap between the cylindrical body and the movable body in cooperation with the movable body and the weight body. The degree of freedom of setting such as vibration for closing the gap can be increased by adjusting the height, mass, and the like. Further, by dividing the internal space into two parts in the vertical direction by the movable body and the weight body, for example, even if the cylindrical body has a stepped shape, these movable bodies are basically located above and below the step. And by arranging the weight body, it is possible to suitably set a gap with the cylindrical body at each position.

  In the present invention, it is possible to provide a reservoir tank that can more reliably suppress leakage of hydraulic oil to the outside due to vibration or the like.

(A) and (b) are the top view and sectional drawing which show one Embodiment of this invention. Operation | movement explanatory drawing of the embodiment. Operation | movement explanatory drawing of the embodiment. (A) (b) (c) is a figure which shows a movable body, a sealing member, and a weight body.

DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, an embodiment of the invention will be described with reference to the drawings.
FIG. 1A is a plan view showing a reservoir tank 1 applied to a hydraulic power steering device, and FIG. 1B is a cross-sectional view taken along line AA in FIG. is there. As shown in the figure, the reservoir tank 1 includes a tank body 10 made of metal or resin for storing hydraulic oil. The tank body 10 has an inflow port and an outflow port (not shown) at the bottom thereof, and hydraulic oil discharged from the actuator flows into the inside through the inflow port, and the internal working oil becomes a hydraulic power source through the outflow port. It is configured to flow out.

  Moreover, the upper end part of the tank main body 10 forms the oil supply port 11 for inject | pouring a hydraulic oil inside. The oil filling port 11 is formed in a substantially cylindrical shape that opens in the vertical direction, and a pair of arcuate locking flanges 12 projecting radially outward at angular positions facing each other are formed on the outer peripheral surface thereof. Is formed. And the cap 20 provided with the ventilation structure for keeping the atmospheric | air pressure inside the tank main body 10 constant is attached to the oil filler 11 so that attachment or detachment is possible. As a result, the lubrication port 11 is closed while maintaining a required outside air (atmosphere) communication state. And the volume change by the change of the hydraulic oil amount in the tank main body 10 is adjusted.

  That is, the cap 20 includes a cap body 21 made of resin and a cap cover 22 that covers the upper side of the cap body 21. The cap body 21 has a bottomed substantially cylindrical closing portion 23 having an outer diameter equivalent to the inner diameter of the oil filler port 11 and opening upward, and extends downward from the center of the bottom wall of the closing portion 23. And a stepped substantially cylindrical protrusion 24. The outer circumferential surface of the closing portion 23 is formed with a circumferential groove 23a that is recessed on the inner circumferential side, and an O-ring 25 is attached to the circumferential groove 23a. The closing part 23 closes the opening part of the O-ring 25 in liquid-tight contact with the inner peripheral surface of the oil filling port 11.

  The cap body 21 has a substantially cylindrical partition wall 26 erected from the center of the bottom wall of the closing portion 23. Thereby, the cap main body 21 forms the 1st space S1 arrange | positioned in the center part in the closing part 23, and the cyclic | annular 2nd space S2 surrounding the outer peripheral side of the 1st space S1. Further, the cap body 21 forms a circular third space S3 that is recessed downward from the upper end surface of the protrusion 24. That is, the cap body 21 has a substantially cylindrical partition wall 27 that divides the third space S <b> 3 above the protrusion 24. The partition wall 27 forms a cylindrical body 28 together with the partition wall 26. The inner diameter of the partition wall 27 is set to be smaller than the inner diameter of the partition wall 26, and the partition walls 26 and 27 as a whole have a substantially cylindrical shape with an expanded upper side.

  The partition wall 27 is formed with a plurality of (for example, two) air vent holes 29 that communicate in the radial direction at a predetermined angular position. Accordingly, the third space S3 (first space S1) communicates with the inside of the tank body 10 at the lower portion (partition wall 27) of the cylindrical body 28.

  The cap body 21 has a ring-shaped flange portion 31 that extends radially outward from the upper end of the closing portion 23 and contacts the upper end surface of the oil filler port 11 over the entire circumference. The rib 32 having a plurality of cross-sectional chevron shapes projecting from the end face. The ribs 32 are arranged concentrically so as to surround the outer peripheral side of the closing portion 23, and the height position of each upper end is set equal to the height position of the upper end of the partition wall 26. The ribs 32 are formed with notches (not shown) that open in the radial direction at predetermined predetermined angular positions. The cap body 21 has a pair of hook-shaped engaging protrusions 34 extending from the outer peripheral end of the flange portion 31 at angular positions facing each other. The cap main body 21 is secured to and fixed to the oil supply port 11 by the engagement protrusion 34 being engaged with the lower surface of the engagement flange 12.

  The cap cover 22 is formed in a substantially cylindrical shape with a lid having an inner diameter equivalent to the outer diameter of the flange portion 31, and abuts against the upper end surface of each rib 32 on the lower surface thereof. Accordingly, a plurality of annular spaces defined by the ribs 32 are formed between the lid wall of the cap cover 22 and the flange portion 31, and the plurality of annular spaces are communicated with each other by the notches formed in the ribs 32. To do. The plurality of annular spaces communicating with the outside air in a so-called maze structure through the second space S <b> 2 by sequentially passing through the notches formed in the ribs 32 from the inner peripheral side to the outer peripheral side constitute a labyrinth 33. Note that the upper end surface of the partition wall 26 is close to the lower surface of the lid wall of the cap cover 22 and forms a gap C (see FIG. 2). Accordingly, the first space S1 (third space S3) communicates with the second space S2 in the upper part of the cylindrical body 28 (partition wall 26). The gap C and the labyrinth 33 constitute a ventilation means. The first and third spaces S1 and S3 communicating with each other form an internal space S that extends in the vertical direction by being closed by the lid wall of the cap cover 22.

  As shown in an enlarged view in FIG. 2, a metal or resin movable body 41 is accommodated in the internal space S so as to be slidable in the vertical direction. As shown in FIG. 4A, the movable body 41 has a substantially cylindrical column portion 42 that has an outer diameter equivalent to the inner diameter of the partition wall 27 and fits into the partition wall 27. A plurality of (two) communication grooves 43 having a substantially U-shaped cross section are provided to be recessed radially inward from the outer peripheral surface of the portion 42. These communication grooves 43 have a slit shape extending in the vertical direction, and form a gap C <b> 1 with the cylinder 28. The movable body 41 is accommodated in the internal space S so that the two communication grooves 43 are opposed to the air vent holes 29 in the radial direction. Thus, the air vent hole 29 can communicate with the upper portion of the internal space S, the gap C, and the like (venting means) via the gap C1.

  In the internal space S, a rubber seal member 46 placed on the movable body 41 protruding into the first space S1 is accommodated so as to be slidable in the vertical direction. As shown in FIG. 4B, the seal member 46 is formed in a disc shape and has an annular bent portion 46a that is uneven in the vertical direction along the peripheral edge portion. The seal member 46 has an outer diameter smaller than the inner diameter of the partition wall 26 in the free state (returned to elasticity) and opens the gap C1. Further, the sealing member 46 is elastically deformed so that the bent portion 46a is crushed and spreads in the lateral direction, so that the outer diameter thereof becomes larger than the inner diameter of the partition wall 26 and closes the gap C1.

  Furthermore, a metal or resin weight body 47 placed on the seal member 46 is accommodated in the internal space S so as to be slidable in the vertical direction. As shown in FIG. 4C, the weight body 47 has a substantially cylindrical shape that has an outer diameter smaller than the inner diameter of the partition wall 26 and is loosely fitted to the partition wall 26. Note that the weight of the weight body 47 is set so that the seal member 46 does not elastically deform until the gap C1 is closed.

  Therefore, as shown in FIG. 2, when the elastic deformation of the seal member 46 is little or none, such as when the vehicle vibration is small, the air vent hole 29 passes through the gap C 1 and the gap between the partition wall 26 and the weight body 47. And communicate with the gap C or the like (venting means). As a result, the inside of the tank body 10 communicates with the outside air through the air vent hole 29, the gap C1, the gap between the partition wall 26 and the weight body 47, the gap C, and the labyrinth 33, for example, expanded by oil temperature. Air is discharged to the outside. And the atmospheric pressure inside the tank body 10 is kept constant.

  On the other hand, as shown in FIG. 3, when the movable body 41, the seal member 46, and the weight body 47 (reservoir tank 1) move up and down significantly, such as when the vehicle vibration is large, the movable body 41 and the weight body 47 are accelerated. Then, by contacting the lower surface and the upper surface of the seal member 46, the bent portion 46a is crushed and elastically deformed into a flat plate shape so that the seal member 46 spreads in the lateral direction. And the sealing member 46 closes the clearance gap C1 because an outer peripheral end substantially adheres to the inner peripheral surface of the partition wall 27 (tubular body 28). Thereby, the communication between the air vent hole 29 and the gap C or the like (venting means) is temporarily blocked, and the hydraulic oil is prevented from leaking to the outside. Note that the clearance C1 is temporarily closed, and it is not necessary to always discharge the air in the tank body 10 to the outside, so that the function of the discharge or the like is not affected.

As described above in detail, according to the present embodiment, the following effects can be obtained.
(1) In this embodiment, when the seal member 46 is in a free state, the seal member 46 opens the gap C1 between the cylindrical body 28 (partition wall 26) and the movable body 41 so that the air vent hole 29 and the gap C are communicated. The Therefore, when the elastic deformation of the seal member 46 is little or not, for example, when the vehicle vibration is small, the gap C1 is opened by the seal member 46, and the air vent hole 29 and the gap C are communicated. Thereby, the air pressure inside the tank body 10 can be kept constant by communicating the inside of the tank body 10 with the outside air. On the other hand, when the movable body 41 or the like significantly moves up and down, for example, when the vehicle vibration is large, the gap C1 is closed by the seal member 46 that is compressed and elastically deformed by the movable body 41 and the like. Accordingly, it is possible to prevent the hydraulic oil inside the tank body 10 that has been bounced off due to vehicle vibration or the like from leaking outside through the gap C1.

  (2) In the present embodiment, the communication between the second space S2 (internal space S) and the outside air is performed by the labyrinth 33 formed between the cap body 21 (flange portion 31) and the cap cover 22, so that the air flow Since the path is complicated, the hydraulic oil inside the tank body 10 can be prevented from leaking outside.

  (3) In the present embodiment, the seal member 46 is elastically deformed so as to close the gap C1 in cooperation with the movable body 41 and the weight body 47, for example, the height and mass of the movable body 41 and the weight body 47. The degree of freedom for setting the degree of vibration or the like that closes the gap C1 can be increased by adjusting the above. Further, by dividing the internal space S into two parts in the vertical direction by the movable body 41 and the weight body 47, even if the cylindrical body 28 has a stepped shape, the movable body 41 is basically located above and below the step. By arranging the weight body 47 and the weight body 47, the gap C1 can be suitably set at each position.

  (4) In the present embodiment, the seal member 46 has an extremely simple structure in which the flexible portion 41a is crushed by the movable body 41 when the movable body 41 or the like moves up and down and elastically deforms so as to spread laterally. The gap C1 can be closed. In particular, the flexible portion 46a can be elastically deformed easily by being concentrically wavy.

  (5) In the present embodiment, the movable body 41 can perform vertical movement in the internal space S in a more stable posture by fitting the column portion 42 to the cylindrical body 28 (partition wall 27). The gap C <b> 1 can be formed by the communication groove 43 that is recessed in the column part 42.

  (6) In the present embodiment, the hydraulic oil inside the tank body 10 leaks to the outside by temporarily closing the gap C1 using the vibration of the cap 20 (reservoir tank 1) accompanying the vibration of the vehicle. Can be suppressed.

In addition, you may change the said embodiment as follows.
In the embodiment, the weight body 47 may be fixed in the internal space S. Further, the weight 47 may be omitted, and the seal member 46 may be compressed only by the movable body 41. Even in this case, when the movable body 41 or the like moves up significantly, such as when the vehicle vibration is large, the movable body 41 and the cap cover 22 (lid wall) come into contact with the lower surface and the upper surface of the seal member 46. The bent portion 46a is crushed and elastically deformed into a flat plate shape so that the seal member 46 spreads in the lateral direction. Therefore, even if it changes in this way, communication with the air vent hole 29, the clearance gap C etc. (ventilating means) can be interrupted | blocked temporarily, and it can suppress that hydraulic fluid leaks outside.

  -In the above-mentioned embodiment, you may form the crevice between a cylinder and a movable body in the range of play between them, for example by loosely fitting a movable body to a cylinder. Moreover, the clearance gap between a cylinder and a movable body may be set over the perimeter, and may be set partially in the predetermined angle position. And as long as the seal member can close the entire gap between the cylinder and the movable body during elastic deformation, the seal member may open the entire gap in a free state or may be partially opened. Good.

In the embodiment, the cylindrical body 28 (partition walls 26 and 27) may have a cylindrical shape with a constant inner diameter over the entire length.
The present invention may be applied to other than the reservoir tank of the power steering device.

Next, the technical idea that can be grasped from the above embodiment and other examples will be described below.
(A) In the reservoir tank according to any one of claims 1 to 3,
The seal member has an annular bent portion that is uneven in a vertical direction along a peripheral edge portion, and is elastically deformed so that the bent portion is crushed and spread in the lateral direction by the movable body when the movable body moves up. A reservoir tank characterized by: According to this configuration, the seal member has an extremely simple structure in which the flexible member is elastically deformed so that the flexible part is crushed and spread in the lateral direction when the movable body is moved upward. A gap between the movable bodies can be closed.

(B) In the reservoir tank according to any one of claims 1 to 3 and (a) above,
2. The reservoir tank according to claim 1, wherein the movable body includes a column portion that fits into the cylindrical body, and a communication groove that is recessed in the column portion and extends in the vertical direction. According to this configuration, the movable body can perform vertical movement in the internal space with a more stable posture by fitting the column portion to the cylindrical body. And the clearance gap between the said cylinder and the said movable body can be formed with the said communicating groove recessedly provided in the said pillar part.

  DESCRIPTION OF SYMBOLS S ... Internal space, C ... Gap (ventilation means), C1 ... Gap, 1 ... Reservoir tank, 10 ... Tank main body, 11 ... Oil filling port, 20 ... Cap, 21 ... Cap main body, 22 ... Cap cover, 28 ... Cylindrical body 29 ... Air vent holes (vent holes), 33 ... Labyrinths (vent means), 41 ... Movable bodies, 46 ... Seal members, 47 ... Weight bodies.

Claims (3)

In a reservoir tank comprising a tank body in which an oil filling port is formed at the top and storing hydraulic oil, and a cap attached to the oil filling port to close the oil filling port,
The cap is
A cylinder having an internal space extending in the vertical direction;
In the lower part of the cylindrical body, a vent hole communicating the inside of the tank body and the internal space;
A ventilation means for communicating the internal space and the outside air at the upper part of the cylinder;
A movable body accommodated in the internal space so as to be slidable in the vertical direction and capable of communicating the ventilation hole and the ventilation means via a gap between the cylindrical body;
The vent is mounted on the movable body and accommodated in the internal space, and in a free state, has an outer diameter smaller than the inner diameter of the cylindrical body, thereby opening a gap between the cylindrical body and the movable body. and communicating said vent means, when Ru is compressed by movable body during upward movement of the movable body, by diameter to the same outer diameter as the inner diameter of at least the cylindrical body, a clearance of the cylindrical body and the movable body A reservoir tank comprising a seal member that is elastically deformed so as to be closed. The reservoir tank according to claim 1, wherein
The cap is
A cap body which is oil-tightly attached to the oil filling port and closes the oil filling port;
A cap cover covering the upper side of the cap body;
The reservoir tank according to claim 1, wherein the ventilation means is a labyrinth formed between the cap body and the cap cover on an outer peripheral side of the cylindrical body. The reservoir tank according to claim 1 or 2,
The seal member is placed on the seal member and slidably accommodated in the internal space together with the seal member, and the seal member closes the gap between the cylindrical body and the movable body in cooperation with the movable body. A reservoir tank comprising a weight body that is elastically deformed.