JP2015155649A - relief valve device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a relief valve device capable of suppressing rise of an oil pressure in an intermediate frequency zone of an engine particularly in a state that an oil temperature is low, and improving efficiency and durability, in an oil pump of a vehicle engine and the like.

SOLUTION: A relief valve device includes a relief valve composed of a valve element 4, a valve path 2, and a valve housing A having a first discharge portion 33 disposed at one side of a small-diameter path portion 21 and a large-diameter path portion 22 of the valve path, and a second discharge portion 34 disposed at the other side, a main relief flow channel 31 communicated with one side of the small-diameter path portion 21 and the large-diameter path portion 22, an auxiliary relief flow channel 32 communicated with the other side, a solenoid valve 6 mounted in the auxiliary relief flow channel 32 for communicating or blocking the auxiliary relief flow channel 32, and a spring 8 for elastically biasing the valve element 4 in the direction opposite to a direction of force by oil pressure. A second discharge portion 34 is kept in an opened state at a terminal end position of stroke in the valve path 2, of the valve element 4 or near the terminal end position.

COPYRIGHT: (C)2015,JPO&INPIT

Description

  The present invention relates to an oil pump for a vehicle engine or the like, in particular in a state where the oil temperature is low, a relief valve capable of suppressing an increase in hydraulic pressure in the middle rotation speed range of the engine and improving efficiency and durability. Relates to the device.

  The applicant has already invented an invention for solving the problems of Patent Document 1 (Japanese Patent Laid-Open No. 5-26024), which has already been disclosed as a prior art. The problem of Patent Document 1 is that the length of the mounting length of the spring is changed in order to operate the mechanical relief valve in two stages. In order to change the length of the spring, Means to supply hydraulic pressure from both sides.

Switching the hydraulic pressure to the left and right is done by switching the oil path with a solenoid valve. However, in order to supply hydraulic pressure from the left and right sides of the mechanical relief valve, it is necessary to provide oil paths on both the left and right sides. Yes, the overall length of the mechanical relief valve installation becomes longer. In addition, the mechanical relief valve configuration increases not only the valve body and coil spring, but also the piston, which increases the number of components, so these components must also be incorporated into the layout (design). This increases the overall length of the relief valve installation.

Japanese Patent Laid-Open No. 5-26024 JP 2012-202345 A

  As described above, this Patent Document 1 has a problem that the overall length of the relief valve is long, and therefore cannot be reduced in size. -202345) is shown by the present applicant. In Patent Document 2, the normal operation has no problem and exhibits a sufficient effect.

  By the way, the relief valve device in Patent Document 2 has a narrow installation space depending on the mounted vehicle, and there may be a case where there is not enough space for arranging the relief valve device. Therefore, when there is not enough space for arranging the relief valve device, it is necessary to reduce the size of the relief valve device.

  For example, the relief valve device may be reduced in size by reducing the opening area of the main discharge channel. In addition, the size of the relief valve device may be reduced by limiting the amount (stroke amount) by which the relief valve (valve element) can move in the axial direction. And in the case of high oil temperature, the relief valve apparatus can perform the relief operation | movement along a target in the low rotation speed area of an engine, a middle rotation speed area, and a high rotation speed area.

  By the way, in patent document 2, when the viscosity of oil is high due to low oil temperature, the following phenomenon may occur. When the opening area of the main discharge channel is small, the oil becomes difficult to pass through, so the increase in hydraulic pressure becomes more remarkable, and the relief valve is moved to the upper side (the side on which the spring 8 is further contracted) even at the same engine speed. .

In the middle engine speed range, a substantially constant low oil pressure can be maintained over a substantially entire range of the medium speed range by a normal relief operation at a high oil temperature, and fuel consumption can be improved. However, in the case of a low oil temperature in the middle speed range of the engine, the limit point of the range in which the relief valve can be moved by hydraulic pressure at the later stage of the middle speed range and immediately before the high speed range, that is, the end of the stroke. The relief valve may continue to move until it reaches

  When the end of the stroke of the relief valve is reached, the opening area of the main discharge channel for discharging oil does not increase, and the relief operation cannot catch up with the increase in hydraulic pressure. As a result, the hydraulic pressure increases as the engine speed increases. In addition, when the amount of stroke of the relief valve is limited to a short size by reducing the size of the device, the amount that the relief valve can move upward is also reduced, and the relief valve can move in the medium engine speed range. The limit is reached soon.

  As described above, even when the end of the relief valve stroke is reached, the discharge opening area of the main discharge flow path does not increase any more, and the hydraulic pressure decreases when the engine speed further increases. It cannot be maintained in a state, and the hydraulic pressure increases as the engine speed increases. And, when the oil temperature is low and in the region near the high engine speed in the medium engine speed range, the end of the relief valve stroke may be reached. In such a case, the hydraulic pressure increases, As a result, engine friction (friction) increases and fuel consumption decreases.

  The graph of FIG. 13 shows that the hydraulic pressure increases in the latter half of the middle rotation speed range and immediately before the high rotation speed range. A portion surrounded by a circular dotted line in FIG. 13 is an increase in the hydraulic pressure in the middle rotation speed range. And in this oil pressure increase part, a fuel consumption will worsen. Further, when the relief valve moves to the end of the stroke, the spring is contracted to the maximum, so that the spring is set and the durability of the spring may be lowered.

  In addition, the spring settling means that the spring is plastically deformed in the load direction during use, the spring is difficult to return to its original shape, and the spring load is reduced. An object (technical problem to be solved) of the present invention is to improve efficiency and durability in an oil pump for a vehicle engine or the like, particularly in a state where the oil temperature is low, suppressing an increase in hydraulic pressure in the middle rotation speed range of the engine. Is to realize.

  In view of the above, the inventor has intensively and intensively studied to solve the above-described problems. As a result, the inventor of the present invention can be realized by combining a valve body composed of a small diameter portion and a large diameter portion, A relief valve comprising: a valve passage having a first discharge portion provided on one side of the small-diameter passage portion and the large-diameter passage portion; and a second discharge portion provided on the other side. A main relief passage communicating with one side of the small diameter passage portion and the large diameter passage portion, an auxiliary relief passage communicating with the other side, and the auxiliary relief passage attached to the auxiliary relief passage A solenoid valve that communicates with or shuts off the valve body, and a spring that elastically biases the valve body in a direction opposite to the direction of the hydraulic force, and a stroke end position in the valve passage of the valve body or in front of the end position The second discharge part is open near Relief valve device is formed by. As a result, the above problems were solved.

  The invention of claim 2 is the relief valve device according to claim 1, wherein the first discharge portion communicates with the small diameter passage portion, and the second discharge portion is provided in the large diameter passage portion. Solved the above problem. The invention of claim 3 is the relief valve device according to claim 1, wherein the first discharge portion communicates with the large-diameter passage portion, and the second discharge portion is provided in the small-diameter passage portion. Solved the above problem.

  The invention according to claim 4 is the relief valve device according to any one of claims 1, 2, or 3, wherein the second discharge portion is configured to communicate with the first discharge portion. Solved the problem. The invention of claim 5 is the relief valve device according to any one of claims 1, 2, 3 or 4, wherein the auxiliary relief flow path is branched from the main relief flow path. Solved the above problem.

  In the first aspect of the invention, since the second discharge portion is opened at or near the end position of the stroke in the valve passage of the valve body, the valve body is the end position of the stroke or its end position. The second discharge part opens in front, and the oil in the valve passage can be discharged together with the first discharge part.

  As a result, it is possible to suppress an increase in oil pressure immediately before the high engine speed range in the latter half of the engine at a particularly low oil temperature, and to make the medium engine speed range a stable low oil pressure. Side friction (friction) can be suppressed and fuel consumption can be improved.

  Further, the valve body can open the second discharge part before the valve body reaches the end position of the stroke or before reaching the end position, that is, before the valve body reaches, and can discharge the oil in the valve passage together with the first discharge part. As a result, the spring that elastically biases the valve body does not shrink to the limit, has a margin, and does not cause settling, so that the durability of the spring can be improved.

  Since the second discharge portion is disposed near the maximum stroke amount of the valve body, it does not affect the normal control, and can normally perform the target control regardless of the oil temperature. The second discharge portion is not relieved at a high oil temperature, and is disposed at a position where the relief is performed when the stroke amount is maximized only at a low oil temperature.

  As a result, the oil pressure in the narrow engine speed region close to the high engine speed range in the medium engine speed range, which is slightly lower than the engine speed at which only the low oil temperature at which the oil pressure tends to increase, jumps up, is increased. It is possible to reduce and reduce the other oil temperatures and the engine speed, and control can usually be performed as intended.

  In the invention of claim 2, the first discharge part communicates with the small-diameter passage part, the second discharge part is provided in the large-diameter passage part, and the other structure is equivalent to claim 1. Therefore, an effect equivalent to that of the first aspect is obtained. In the invention of claim 3, the first discharge part is in communication with the large-diameter passage part, the second discharge part is provided in the small-diameter passage part, and the other structure is the same as in claim 1. Therefore, an effect equivalent to that of the first aspect is obtained.

  In the invention of claim 4, the second discharge part is configured to communicate with the first discharge part, and the circuit in the relief can be simplified. In the invention of claim 5, the auxiliary relief flow path is branched from the main relief flow path, so that the structure of the main relief flow path and the auxiliary relief flow path can be simplified, and the apparatus can be further reduced in size. Can be realized.

(A) is sectional drawing which shows the oil supply circuit of the engine provided with the structure of 1st Embodiment of this invention, (B) is the (alpha) part enlarged view of (A), (C) is the solenoid of (A). FIG. 4 is a schematic cross-sectional view in which the connection flow path and the auxiliary relief flow path are opened in an enlarged view of the (β) portion of the valve, and FIG. 4D is an enlarged view of the (β) portion of the solenoid valve of FIG. It is a schematic sectional drawing which opened the auxiliary | assistant discharge flow path. (A) is a schematic cross-sectional view showing the action of relief oil in the low speed range of the first embodiment of the present invention, (B) is a detailed cross-sectional view showing the operation of the solenoid valve in the (I) part of (A) It is. (A) is a schematic cross-sectional view showing the action of the relief oil at the initial stage of the middle speed range of the first embodiment of the present invention, and (B) is a detail showing the operation of the solenoid valve in the (II) part of (A). It is sectional drawing. (A) is schematic sectional drawing which shows the effect | action of the relief oil in the middle period of 1st Embodiment of 1st Embodiment of this invention, (B) is a detail which shows operation | movement of the solenoid valve in the (III) part of (A). It is sectional drawing. (A) is a schematic cross-sectional view showing the action of the relief oil in the latter stage of the medium rotation speed range of the first embodiment of the present invention, and (B) is a detail showing the operation of the solenoid valve in the (IV) part of (A). It is sectional drawing. (A) is a schematic cross-sectional view showing the operation when relief is not performed immediately after the start of the high rotation speed range of the first embodiment of the present invention, and (B) is a solenoid valve in the (V) part of (A). It is a detailed sectional view showing the operation of. (A) is a schematic cross-sectional view showing the action when relief is performed in the high speed range of the first embodiment of the present invention, and (B) shows the operation of the solenoid valve in the (VI) part of (A). FIG. It is a schematic sectional drawing which shows the effect | action of the relief oil in the low rotation speed range of 2nd Embodiment of this invention. It is a schematic sectional drawing which shows the effect | action of the relief oil in the initial stage of the medium speed range of 2nd Embodiment of this invention. It is a schematic sectional drawing which shows the effect | action of the relief oil in the latter period of the medium speed range of 2nd Embodiment of this invention. It is a schematic sectional drawing which shows the effect | action of the relief oil in the high rotation speed area of 2nd Embodiment of this invention. It is a graph which shows the engine speed in the low oil temperature state in this invention, and the relationship between oil_pressure | hydraulic. It is a graph which shows the engine speed and oil pressure in the low oil temperature state in a prior art.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. There are a plurality of embodiments of the present invention, and the first embodiment will be described first. The configuration of the present invention mainly includes a housing A, a valve body 4, a solenoid valve 6, a spring 8, and the like. The casing 1 of the housing A accommodates a valve body 4 and is fitted with a solenoid valve 6 (see FIG. 1A).

  In the housing 1, a valve passage 2, a main relief flow path 31, an auxiliary relief flow path 32, and the like are formed. The valve passage 2 is a part in which the valve body 4 is accommodated. In the valve passage 2, a cylindrical small-diameter passage portion 21 and a large-diameter passage portion 22 having different inner diameters are formed in the same axis. Specifically, a large-diameter passage portion 22 having a large diameter dimension is formed on the opening side with respect to the surface of the housing 1, and a small-diameter passage portion 21 having a small diameter dimension is formed on the back side thereof.

  The boundary between the small diameter passage portion 21 and the large diameter passage portion 22 has a flat circumferential step surface portion 23. Here, in the present invention, the vertical direction is not particularly limited, but in order to make the explanation easy to understand, the passage direction of the valve passage 2 is the vertical direction, and the large-diameter passage of the valve passage 2 When the portion 22 is set to be higher than the small-diameter passage portion 21, the large-diameter passage portion 22 side is set to the upper side (see FIG. 1A).

  The main relief channel 31 is a channel formed so as to communicate from the outside of the housing 1 toward the tip surface of the valve channel 2 on the lower side of the small-diameter channel portion 21 [see FIG. 1 (A)]. The main relief channel 31 is formed in a direction perpendicular to the valve passage 2, but the formation state is not limited. The tip portion of the main relief channel 31 is formed so as to communicate with the tip surface (back side surface) of the small-diameter passage portion 21 of the valve passage 2. That is, the main pressure receiving surface 41a of the valve body 4 described later is configured to be easily subjected to the pressure of oil to be relieved (exhaust pressure, discharged).

  A first discharge portion 33 communicating with the outside of the housing 1 is formed in the small diameter passage portion 21 of the valve passage 2. The first discharge part 33 has a function of returning the relief oil flowing into the small diameter passage part 21 from the main relief flow path 31 to the suction side of the oil pump 91 or an oil pan (not shown).

  The auxiliary relief channel 32 is branched from the main relief channel 31 inside the housing 1. Part of the oil flowing through the main relief channel 31 flows into the auxiliary relief channel 32 (see FIG. 1C). In addition, the auxiliary relief channel 32 is not branched from the main relief channel 31, and may be formed in the housing A as a separate channel from the main relief channel 31.

  However, in this case, in the circulation flow path between the oil pump 91 and the engine 92, the auxiliary relief flow path 32 is on the downstream side of the main relief flow path 31, and particularly downstream of the oil filter (not shown). If arranged, it is more preferable because control can be performed with hydraulic pressure with less pulsation.

  A solenoid valve chamber 323 is formed at the upper tip of the auxiliary relief flow path 32 (on the side opposite to the branching portion). The solenoid valve chamber 323 accommodates a direction control unit 61 of the solenoid valve 6 described later. Here, the solenoid valve 6 is mounted from the outside of the housing 1, and the upper end of the auxiliary relief flow path 32 penetrates the surface of the housing 1 for assembly of the solenoid valve 6. .

  The auxiliary relief flow path 32 communicates with the large diameter passage portion 22 of the valve passage 2 via the solenoid valve 6. Further, in the auxiliary relief flow path 32, the flow path between the solenoid valve 6 and the large diameter passage portion 22 is referred to as a connection flow path 321. The connection channel 321 belongs to the auxiliary relief channel 32 and is a part of the auxiliary relief channel 32.

  The auxiliary relief flow path 32 is configured to be switched to either one of communication and blocking with the large-diameter passage portion 22 by the solenoid valve 6. Further, an auxiliary discharge channel 322 is formed from the auxiliary relief channel 32 via the solenoid valve 6. The auxiliary discharge channel 322 serves to return oil to the suction side of the oil pump 91 or to the oil pan. Openings inside the auxiliary relief flow channel 32 of the connection flow channel 321 and the auxiliary discharge flow channel 322 are formed together in the range of the solenoid valve chamber 323.

  Further, a second discharge portion 34 is formed in the large diameter passage portion 22. The second discharge portion 34 releases relief oil flowing into the large-diameter passage portion 22 of the valve passage 2 toward the oil pan, or is connected to the suction side of the oil pump 91 to return the oil to the oil pump 91. It plays a role.

  The second discharge part 34 is used in an oil relief operation or a discharge operation particularly when the oil temperature is low. The second discharge portion 34 is in a state where the oil temperature is low, the auxiliary relief flow path 32 is in communication, and the spring 8 that elastically biases the valve body 4 in a direction opposite to the direction in which pressure is received is contracted. The valve body 4 is reached at a position where the valve body 4 is reached or slightly opened in front of the reached position.

  That is, the valve body 4 moves against the elastic biasing direction of the spring 8 by the pressure of the oil flowing into the valve passage 2 from the main relief channel 31 and the auxiliary relief channel 32, and the end t of the stroke S thereof. The valve body 4 opens the second discharge portion 34 at or near the position where the oil is discharged, and discharges the oil to the outside of the valve passage 2. Here, the stroke S of the valve body 4 is the maximum when the spring 8 that elastically biases the valve body 4 by receiving the oil pressure from the stationary initial state where the valve body 4 is not subjected to the oil pressure when the oil temperature is low. It is the length of the stroke to the position where it is in a contracted state as much as possible.

  The end t of the stroke S is the position of the valve body 4 when the spring 8 that elastically biases the valve body 4 contracts to the maximum when the oil temperature is low. Therefore, the end position t of the stroke S or the vicinity thereof is a position where the valve body 4 does not reach the end position t, and the spring 8 is not maximally contracted and has a contraction allowance.

  Further, the starting end of the stroke S is a position where the valve body 4 is stopped by receiving only the elastic biasing force of the spring 8 without receiving the hydraulic pressure. Therefore, the position formed in the valve passage 2 of the second discharge portion 34 is a position on the near side or near the position of the end t of the stroke S and a position where the valve body 4 can be opened by passing the valve body 4. Is formed.

  The valve body 4 includes a small-diameter portion 41 and a large-diameter portion 42, both are formed in a cylindrical shape, and the small-diameter portion 41 and the large-diameter portion 42 are integrally formed along the axial direction. The valve body 4 is used in a state in which the small-diameter portion 41 is downward and the large-diameter portion 42 is upward and the axial direction is vertical. The lower end of the small diameter portion 41 is a main pressure receiving surface 41a, and a step portion formed at the boundary between the small diameter portion 41 and the large diameter portion 42 becomes the auxiliary pressure receiving surface 42a.

  The axial dimension of the valve body 4 is longer than the overall length of the small diameter passage portion 21 of the valve passage 2. Specifically, the axial length of the small diameter portion 41 may be a dimension that is slightly larger than the total length of the small diameter passage portion 21. As a result, the valve body 4 accommodated in the valve passage 2 always has a gap between the auxiliary pressure receiving surface 42a and the step surface of the valve passage 2, and the auxiliary pressure receiving surface 42a reduces the pressure of the relief oil. The structure can be easily received.

  A specific embodiment of the solenoid valve 6 includes a direction control unit 61 and an electromagnetic control unit 62. The direction control unit 61 is housed in the solenoid valve chamber 323 of the auxiliary relief flow path 32, and the electromagnetic control unit 62 is attached to the recessed installation unit 11 formed in the housing 1. Between the direction control part 61 of the solenoid valve 6 and the solenoid valve chamber 323, an O-ring for partitioning the oil passage in a sealed manner is installed to prevent oil leakage. The solenoid valve 6 is fixed to the housing A by fixing means such as screwing.

  The solenoid valve 6 is a valve that serves to control the direction in which oil flows, and has a direction control unit 61, by which the auxiliary relief flow path 32, the connection flow path 321, and the auxiliary discharge flow path. The oil flow direction between 322 is controlled. The direction control unit 61 uses the connection flow path 321 as a basic flow path through which oil can always flow, and the connection flow path 321 communicates with the auxiliary relief flow path 32, or the connection flow path 321 and the auxiliary discharge flow path 322. One of the communication is selectively switched.

  Control operation of the solenoid valve 6 is performed by the electromagnetic control unit 62. In addition, when either one of the communication between the connection flow path 321 and the auxiliary relief flow path 32 or the communication between the connection flow path 321 and the auxiliary discharge flow path 322 is selected, the other communication is blocked. Yes, oil distribution is impossible.

  The direction control unit 61 of the solenoid valve 6 has a cylindrical shape and is accommodated in a solenoid valve chamber 323 that is a cylindrical gap portion having a substantially equal diameter (see FIG. 1A). The direction control unit 61 includes an axial direction control channel 61a, a first diameter direction control channel 61b, and a second diameter direction control channel 61c. The axial direction control channel 61 a has an opening through which oil flows into the end surface of the direction control unit 61 in the axial direction, and a part of the oil flowing through the main relief channel 31 flows into the auxiliary relief channel 32. [See FIG. 1 (C)].

  The first diameter direction control flow path 61b and the second diameter direction control flow path 61c are formed at two different locations along the axial direction, and the first diameter direction control flow path 61b is located below and has a second diameter. The direction control channel 61c is located above. The first diametric control channel 61b and the second diametric control channel 61c are communicated by the axial control channel 61a. A location where the axial direction control flow path 61a and the lower first diameter direction control flow path 61b intersect is configured as a valve chamber 61d, and a spherical valve member 64 is accommodated in the valve chamber 61d [FIG. 1 (C), (D)].

  The lower first diameter direction control flow path 61 b communicates with the connection flow path 321. Further, the upper second diameter direction control channel 61 c communicates with the auxiliary discharge channel 322. Furthermore, with both ends of the first diametrical control flow path 61b as diameters, outer peripheral grooves 61e are formed on the outer periphery of the directional control section 61 so as to go around once, and both end parts of the second diametrical control flow path 61c. The outer peripheral groove 61f is formed on the outer periphery of the direction control unit 61 so as to turn around once.

  By the outer circumferential grooves 61e and 61f, the direction control unit 61 can be freely set in the rotational direction. Normally, the valve member 64 is pressed below the valve chamber 61d by the operating shaft 63 in a state where the solenoid valve 6 is OFF, and the axial direction control flow path 61a and the first diametrical direction control flow on the lower side are pressed. The communication with the passage 61b is cut off to make it impossible for the relief oil to flow in (see FIG. 1D).

  The electromagnetic control unit 62 has an operation shaft 63, and the operation shaft 63 reciprocates so as to move up and down along the axial direction. This operation is performed by electromagnetic control of the electromagnetic control unit 62. The operating shaft 63 descends to press the valve member 64 downward to block the inflow of relief oil [see FIG. 1 (D)]. Further, when the operating shaft 63 is raised, the valve member 64 is released so that relief oil can flow in (see FIG. 1C).

  Next, the direction control action of the solenoid valve 6 will be described. The relief valve device of the present invention is incorporated in the oil circulation passage S between the oil pump 91 and the engine 92. Part of the oil flows from the oil circulation channel S into the main relief channel 31 of the housing A. The oil flowing into the main relief flow path 31 communicates with the small diameter passage portion 21 of the valve passage 2, and the oil presses the main pressure receiving surface 41 a of the valve body 4 as it is.

  Further, part of the oil that has flowed into the main relief channel 31 also flows into the auxiliary relief channel 32. The direction of communication of the oil flowing into the auxiliary relief flow path 32 is controlled by the solenoid valve 6, and the auxiliary relief flow path 32 and the connection flow path 321 are brought into communication (open) or blocked (closed). The flow path 32 and the large diameter passage portion 22 of the valve passage 2 are communicated or blocked.

  When the solenoid valve 6 is off (OFF), the operation shaft 63 of the electromagnetic control unit 62 is in a state of pressing the valve member 64 in the direction control unit 61 downward, and in the valve chamber 61d, the operation shaft 63 is connected to the axial direction control flow path 61a. The inlet to the auxiliary relief channel 32 is blocked. Thereby, the inflow of the relief oil from the auxiliary relief channel 32 to the connection channel 321 is stopped. Further, the large-diameter passage portion 22, the connection flow path 321 and the auxiliary discharge flow path 322 communicate with each other. As a result, the large-diameter passage portion 22 is connected to the atmosphere, and the space is not sealed in the large-diameter passage portion 22.

  When the solenoid valve 6 is on (ON), the operation shaft 63 of the electromagnetic control unit 62 is lifted to release the valve member 64 in the direction control unit 61 from being pressed and to be in a free state. As a result, the inlet of the axial direction control channel 61a and the auxiliary relief channel 32 can be opened in the valve chamber 61d, and the momentum of the inflow of relief oil from the auxiliary relief channel 32 pushes the valve member 64 upward. Thus, the relief oil flows into the direction control unit 61.

  In the valve chamber 61d, the valve member 64 blocks an opening that communicates the lower first diameter direction control flow path 61b and the upper second diameter direction control flow path 61c. As a result, the auxiliary relief flow path 32, the connection flow path 321 and the large-diameter passage portion 22 are communicated, and the relief oil is fed into the large-diameter passage portion 22, and the relief oil passes through the auxiliary pressure receiving surface 42a of the valve body 4. Can be pressed.

  Next, the relief operation of the present invention in each rotation speed region of the engine 92 will be described. In the relief valve device of the present invention, a relief operation is performed according to the rotational speed of the engine 92, and the relief operation varies in the low rotational speed range, the middle rotational speed range, and the high rotational speed range.

  Here, the low rotation speed range, the middle rotation speed range, and the high rotation speed range in the present invention will be described. The low rotation speed range is a rotation speed range in which the hydraulic pressure increases in proportion to the rotation speed. In terms of the engine rotation speed, it varies from vehicle to vehicle, but is idling rotation speed to 1000 rpm.

  The middle rotation speed range is a rotation speed range that is substantially constant at a low oil pressure regardless of the rotation speed, or a first-stage relief pressure. For example, in terms of engine speed, it is 1000 rpm to 3500 rpm, although it varies from vehicle to vehicle.

The high engine speed range is a control that increases the hydraulic pressure as the engine speed increases, and is a higher engine speed range than the engine speed that increases the hydraulic pressure. Further, the high rotation speed range is also a rotation speed range that becomes the second-stage relief pressure. For example, in terms of engine speed, it will be 3500rpm or more, although it will vary from vehicle to vehicle. The hydraulic control as described above is performed. Here, the oil temperature is lower than usual and the viscosity is high.

First, a relief operation in a low engine speed range will be described (see FIG. 2). Here, the low rotational speed range is a range where the rotational speed is from idling to 1000 rpm. That is, this is the rotational speed range from when the hydraulic pressure is zero to when the hydraulic pressure is switched to the first relief pressure. The solenoid valve 6 is turned on by an operation command. In the electromagnetic control unit 62, the operation shaft 63 releases the pressing of the valve member 64, and allows the auxiliary relief channel 32 and the axial direction control channel 61a to communicate with each other.

  The released valve member 64 is pushed up by the pressure of the relief oil, and the auxiliary relief flow path 32, the axial direction control flow path 61a, and the first diameter direction control flow path 61b communicate with each other, and at the same time, pushed up by the pressure of the relief oil. The valve member 64 blocks communication between the axial direction control channel 61a and the second diametrical direction control channel 61c [see FIG. 2 (B)]. As a result, the auxiliary relief flow channel 32 and the connection flow channel 321 communicate with each other via the direction control unit 61.

  The relief oil flows into the large-diameter passage portion 22 through communication with the auxiliary relief passage 32, the direction control portion 61, and the connection passage 321. Then, the relief oil that has flowed into the large-diameter passage portion 22 presses the auxiliary pressure receiving surface 42 a of the valve body 4, and the relief oil that has flowed into the small-diameter passage portion 21 from the main relief flow passage 31 is the main pressure-receiving surface of the small-diameter passage portion 21. 41a is pressed, but does not move due to insufficient force (see FIG. 2A). Thus, in the low rotational speed range, the pressure of the relief oil is low, and the valve body 4 remains substantially stationary and does not perform relief.

  Next, the relief operation in the middle speed range of the engine 92 will be described (see FIGS. 3 and 4). The medium rotation speed range is a range of the rotation speed from 1000 rpm to 3500 rpm. That is, it is a rotation speed region where the hydraulic pressure is switched from the first relief to the second relief. In this middle rotational speed range, the solenoid valve 6 remains on (ON), and the auxiliary relief flow path 32 communicates with the large-diameter passage portion 22 of the valve passage 2. Specifically, in the electromagnetic control unit 62, the operation shaft 63 releases the pressing of the valve member 64, and allows the auxiliary relief flow channel 32 and the axial control flow channel 61a to communicate with each other.

  The released valve member 64 is pushed up by the pressure of the relief oil, and the auxiliary relief flow path 32, the axial direction control flow path 61a, and the first diameter direction control flow path 61b communicate with each other, and at the same time, pushed up by the pressure of the relief oil. The valve member 64 blocks communication between the axial direction control flow path 61a and the second diameter direction control flow path 61c [see FIG. 3B]. As a result, the auxiliary relief flow channel 32 and the connection flow channel 321 communicate with each other via the direction control unit 61.

  The relief oil flows into the large-diameter passage portion 22 through communication with the auxiliary relief passage 32, the direction control portion 61, and the connection passage 321. Then, the relief oil that has flowed into the large-diameter passage portion 22 presses the auxiliary pressure receiving surface 42 a of the valve body 4, and the relief oil that has flowed into the small-diameter passage portion 21 from the main relief flow passage 31 is the main pressure-receiving surface of the small-diameter passage portion 21. The valve body 4 is moved together with the operation of pressing 41a [see FIG. 3 (A)].

  As a result, the pressure resistance of the valve body 4 increases against the spring 8 by increasing the pressure receiving area of the valve body 4 by the relief oil that presses each of the main pressure receiving surface 41a and the auxiliary pressure receiving surface 42a. For this purpose, the valve body 4 moves in the direction in which the spring 8 is compressed.

  As the rotational speed increases in the middle rotational speed range of the engine 92, the valve body 4 continues to move as described above. As a result, the main pressure receiving surface 41a of the small-diameter portion 41 reaches the axial position of the first discharge portion 33, the relief oil can be discharged from the first discharge portion 33, and relief in the middle rotation speed range is started [Fig. 4 (A)]. As a result, optimal relief is performed in the initial and middle periods of the medium speed range of the engine 92, and the oil pressure can be maintained at a low level.

  Here, in the present invention, the engine 92 is divided into an initial period, a middle period, and a latter period in the middle speed range. The initial middle rotation speed range is a low rotation speed range close to the low rotation speed range. That is, the rotation speed range is a relatively short range from the state of transition from the low rotation speed range to the middle rotation speed range. Further, the latter period of the medium rotation speed range means a high rotation speed range close to the high rotation speed range. Therefore, the middle period of the middle rotation speed range is a rotation speed range between the initial stage and the later stage, and is a rotation speed range in a range longer than the rotation speed range of the initial stage and the latter stage.

  If the oil temperature is high and the viscosity of normal oil, only the relief of oil from the first discharge part 33 is shown in the middle speed range of the engine 92 as shown in FIGS. 3 (A) and 4 (A). Thus, the valve body 4 is balanced with the spring 8 at an appropriate position in the stroke S, and is stopped.

  On the other hand, when the oil temperature is low and the oil viscosity is high, the oil pressure in the valve passage 2 continues to rise in the middle speed range of the engine 92, and the valve body 4 is moved. Become. The increase in hydraulic pressure continues in the latter half of the middle rotation speed range and immediately before (or at the moment of reaching) the high rotation speed range. Therefore, the valve body 4 tries to move to the end t of the stroke S. .

  Therefore, as described above, the second discharge portion 34 is opened at the position where the valve body 4 reaches the position where the stroke S reaches the end t, or in the vicinity thereof, and the oil is discharged to the outside of the valve passage 2. This is the end of the contraction of the spring 8 just before the spring 8 that elastically biases the valve body 4 is in a state of contracting to the maximum extent.

  As described above, the valve body 4 opens the second discharge portion 34 at or near the end t position of the stroke S, and the small-diameter passage portion 21 and the large-diameter passage portion 22 of the valve passage 2 together with the first discharge portion 33. Drain the oil accumulated inside. This suppresses an increase in hydraulic pressure that occurs late in the middle speed range of the engine 92 in the low oil temperature and high viscosity state of the oil and immediately before (or at the moment of reaching) the high speed range. The oil pressure at can be kept substantially constant in a low state, and fuel efficiency can be improved.

  FIG. 12 is a graph showing the relationship between the hydraulic pressure of the engine 92 and the rotational speed in the present invention. This graph shows a substantially horizontal straight line until the end of the middle rotation speed range and immediately before (or the moment of reaching) the high rotation speed range, indicating that there is no rapid increase in pressure.

Next, the relief operation in the region where the rotational speed of the engine 92 is high will be described (see FIGS. 6 and 7). The rotation speed in the high rotation speed range is 3500 rpm or more. That is, the rotation speed range is equal to or higher than the second relief pressure switching rotation speed.

  When reaching the high rotational speed range, the solenoid valve 6 is switched off (see FIG. 6B). That is, the communication between the auxiliary relief flow path 32 and the connection flow path 321 is blocked, and the hydraulic pressure of the relief oil is not transmitted from the auxiliary relief flow path 32 to the large-diameter passage portion 22, and the main pressure receiving surface from the main relief flow path 31. It becomes the press of the relief oil only to 41a [refer to Drawing 6 (A)].

  Therefore, only the main pressure receiving surface 41 a receives pressure on the valve body 4, and the force against the spring 8 is reduced by reducing the pressure receiving area, and the valve body 4 is moved toward the small diameter passage portion 21 by the elastic force of the spring 8. It will be pushed back, the 1st discharge part 33 will again be block | closed by the valve body 4, and the relief of relief oil will stop (refer FIG. 6 (A)). When the valve body 4 is pushed back, the connection flow path 321, the second diameter direction control flow path 61c, and the auxiliary discharge flow path 322 communicate with each other, so that the oil in the large-diameter passage portion 22 passes through the passages. The valve body 4 is returned smoothly (see FIG. 6B).

The rotational speed of the engine 92 is high (3500 rpm), and when the rotational speed is further increased, the pressure of the relief oil immediately increases, and the force due to the hydraulic pressure of the relief oil applied only to the main pressure receiving surface 41a of the valve body 4 Will increase. As a result, the valve body 4 once again moves the valve body 4 in the direction of compression exceeding the elastic force of the spring 8, the small diameter portion 41 opens the first discharge portion 33 again, and the second relief is started. [See FIG. 7A]. The second relief pressure is higher than that in the first.

  And even if the rotation speed of the engine 92 further increases in the high rotation speed range, the solenoid valve 6 is in the OFF state, and the force due to the hydraulic pressure of the relief oil is applied only to the main pressure receiving surface 41a, and the rotation speed increases. At the same time, the valve body 4 is always in a state in which the second relief is made, and maintains an appropriate pressure (see FIG. 7A).

  Next, a second embodiment of the present invention will be described with reference to FIGS. In the second embodiment, as in the first embodiment, the housing mainly includes a housing A, a valve body 4, a solenoid valve 6, a spring 8, and the like. In the housing 1 of the housing A, a valve body 4 is accommodated, and a solenoid valve 6 is mounted. In the valve passage 2, the first discharge portion 33 communicates with the large diameter passage portion 22, and the second discharge portion 34 is provided in the small diameter passage portion 21.

  Here, in the second embodiment, the small-diameter passage portion 21 of the valve passage 2 is set upward and the large-diameter passage portion 22 is set downward in the vertical direction. The main relief channel 31 is formed to communicate from the outside of the housing 1 toward the upper end surface of the large-diameter passage portion 22 of the valve passage 2. Therefore, the small diameter part 41 of the valve body 4 is upward, and the large diameter part 42 is downward. The spring 8 is attached to the large-diameter passage portion 22 and elastically urged so as to push up the valve body 4 upward.

  Further, the auxiliary relief flow path 32 communicates with the small diameter passage portion 21, and specifically communicates with the top of the small diameter passage portion 21. A solenoid valve 6 is mounted at an intermediate position of the auxiliary relief flow path 32, and a connection flow path 321 is formed between the solenoid valve 6 and the small diameter passage portion 21. The structure of the solenoid valve 6 is the same as that in the first embodiment.

  The operation of the engine 92 in the low speed range, medium speed range, and high speed range in the second embodiment is the same as that in the first embodiment described above, but the normal relief operation is performed in the large-diameter passage portion 22. The additional oil discharge of the present invention in the middle rotation speed range is performed by the second discharge section 34 disposed in the small diameter passage section 21 and is performed by the first discharge section 33 disposed.

A ... Housing, 2 ... Valve passage, 21 ... Small diameter passage portion, 22 ... Large diameter passage portion,
31 ... Main relief flow path, 32 ... Auxiliary relief flow path, 321 ... Connection flow path,
322 ... Auxiliary discharge flow path, 33 ... First discharge part, 34 ... Second discharge part, 4 ... Valve body,
41 ... Small diameter part, 41a ... Main pressure receiving surface, 42a ... Auxiliary pressure receiving surface, 42 ... Large diameter part,
6 ... Solenoid valve, 8 ... Spring.

Claims (5)

  A valve body having a small diameter portion and a large diameter portion, a valve passage having a small diameter passage portion and a large diameter passage portion, and a first discharge provided on one side of the small diameter passage portion and the large diameter passage portion. And a relief valve comprising a valve housing having a second discharge portion provided on the other side, a main relief flow path communicating with either one of the small diameter passage portion and the large diameter passage portion, and the other side An auxiliary relief channel communicating with the auxiliary relief channel, a solenoid valve that is attached to the auxiliary relief channel and that communicates or blocks the auxiliary relief channel, and a spring that elastically biases the valve body in a direction opposite to the direction of the hydraulic force. The relief valve device according to claim 1, wherein the second discharge part is opened at or near the end position of the stroke in the valve passage of the valve body.   2. The relief valve device according to claim 1, wherein the first discharge portion communicates with the small diameter passage portion, and the second discharge portion is provided in the large diameter passage portion.   2. The relief valve device according to claim 1, wherein the first discharge portion communicates with the large diameter passage portion, and the second discharge portion is provided in the small diameter passage portion.   4. The relief valve device according to claim 1, wherein the second discharge part is configured to communicate with the first discharge part. 5. 5. The relief valve device according to claim 1, wherein the auxiliary relief channel is branched from the main relief channel.

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