JPH04105913U - oil relief device - Google Patents

Abstract

(57) [Summary] [Purpose] To obtain the desired hydraulic pressure according to the engine speed. [Structure] A first drain hole 4 and a second drain hole 5 are arranged along the axial direction in the valve housing chamber 2 which communicates with the discharge side passage 1 of the pump circuit, and these drain holes 4, 5 A valve body 6 that is biased in the direction of closing the first drain hole 4 is slidably installed inside the first drain hole 4 as the engine speed increases.
and the second drain hole 5 are sequentially opened so that a hydraulic pressure corresponding to the engine rotation range can be obtained.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

The present invention relates to an oil relief device installed in an automobile engine.

0002

[Conventional technology]

Conventional oil relief devices are installed in communication with the discharge side passage of the pump circuit. One drain hole is provided in the valve housing chamber, and this drain hole is opened and closed. Inside the valve body is spring biased in the valve closing direction (direction to close the drain hole). When the fluid pressure in the discharge side passage exceeds the set value, this fluid pressure increases the spring force. Push the valve body back against the pressure to allow some of the oil to escape from the drain hole, thereby The liquid pressure in the discharge side passage is prevented from increasing more than necessary.

0003 Incidentally, this similar structure is shown in Japanese Utility Model Application Publication No. 63-52909, etc.

0004

[Problem that the idea aims to solve]

In the case of conventional oil relief devices, only one drain hole is provided in the valve housing chamber. This structure minimizes the rise in hydraulic pressure when the engine reaches high rotational speeds. Therefore, it is necessary to increase the diameter of the drain hole. However, in this way the drain hole If the diameter is increased, setting the relief pressure to a small value will allow the engine to run in a region where the engine speed is high. On the other hand, if the relief pressure is set high, the engine will not be able to obtain sufficient hydraulic pressure. Excessive fluid pressure will be supplied to the pump circuit in the region where the engine rotation speed is low. Therefore, it is not possible to obtain the desired hydraulic pressure in both the low and high engine speed ranges. stomach.

[0005] Therefore, the present invention can obtain the desired hydraulic pressure according to the engine rotation range. The present invention aims to provide an oil relief device.

[0006]

[Means to solve the problem] The present invention is a means to solve the above-mentioned problems by improving the discharge side passage of the pump circuit. A drain hole is provided in the valve housing chamber communicating with the valve chamber, and the drain hole is closed. When the valve body that is biased in the direction is slidably installed and the fluid pressure in the discharge side passage increases, , an oil relief in which the valve body slides against force to open the drain hole. In the device, a plurality of the drain holes are arranged along the axial direction of the valve housing chamber.

[0007]

[Effect]

As the engine speed gradually increases and the hydraulic pressure in the discharge passage increases, first, The valve body slides in the valve housing chamber against the force to open the first drain hole and remove this drain. Allow some of the oil to escape from the hole. From this state, the engine speed will further increase. Then, the valve body slides further against the force and opens the next drain hole. Allow some of the oil to escape through the drain hole and the first drain hole. In this way, the engine speed As the engine ascends, the drain holes are opened one after another, allowing fluid pressure to be obtained according to the engine's rotation range. Become so.

[0008]

【Example】

Next, an embodiment of the present invention will be described based on FIGS. 1 to 5.

[0009] 1 to 4, 1 is the discharge side passage of the pump circuit, and 2 is the discharge side passage of the pump circuit. This is a valve housing chamber that communicates with the side passage 1 through the passage 3. On the side wall of the valve housing chamber 2, there is a A first drain hole 4 and a second drain hole 5 are provided along the axial direction, and This valve housing chamber 2 includes a valve body 6 for opening and closing the first and second drain holes 4 and 5, and a valve body 6 for opening and closing the first and second drain holes 4 and 5. A spring that urges the valve body 6 in the valve closing direction (direction that closes the first and second drain holes 4 and 5) A ring 7 is installed inside, and the valve body 6 is closed to the first and second doors while the fluid pressure in the discharge side passage 1 is low. When the lane holes 4 and 5 are closed and the hydraulic pressure increases from there, the valve body 6 is moved by the spring 7. It slides in the valve housing chamber 2 against the force and passes through the first drain hole 4 and the second drain hole 5. It is designed to open sequentially for 3.

0010 The valve body 6 is formed into a cylindrical shape with a bottom, and an annular groove 8 of a predetermined width is formed on the central outer peripheral surface of the valve body 6. At the same time, a through hole 9 of a predetermined diameter is formed in the annular groove 8 to pass through the inner and outer surfaces of the peripheral wall of the valve body 6. is formed. The annular groove 8 opens the first drain hole 4 or the third drain hole 4 as the valve body 6 is displaced. This overlaps the second drain hole 5 and thereby the first drain hole 4 and the second drain hole 4. The through hole 9 is electrically connected to the inlet hole 5 so that a part of the oil in the discharge side passage 1 can escape. It has become. Note that the width b of the annular groove 8 is set to be the same as the diameter of the first drain hole 4, The width a of the valve head 10 (the portion from the annular groove 8 to the tip of the valve body 6) is equal to the width a of the first drain. The distance d between the drain hole 4 and the second drain hole 5 is set to be the same. Also, 11 in the figure indicates a back pressure relief hole provided on the back chamber 2a side of the valve housing chamber 1.

[0011] In the above configuration, if the engine speed gradually increases, the engine speed While is extremely low, both the first and second drain holes 4 and 5 are blocked by the valve body 6. (There is no conduction with passage 3), so the fluid pressure in discharge side passage 1 is low pressure. It increases rapidly until it reaches the set value A (see FIG. 5) on the side. And the discharge side passage When the hydraulic pressure of 1 reaches the set value A, the valve body 6 is moved by the spring 7 as shown in FIGS. 1 and 2. The through hole 9 and the first drain hole 4 are displaced against the spring force, and the oil is drained. The fluid is released from the first drain hole 4 to suppress a sudden increase in fluid pressure in the discharge side passage 1.

0012 In this state, only the first drain hole 4 is open to allow oil to escape. Since the opening area is relatively small, as the engine speed increases, As a result, the hydraulic pressure in the discharge side passage 1 increases little by little.

[0013] Further, as the engine speed increases, the hydraulic pressure in the discharge passage 1 increases to the set value B (Fig. 5 reference. ), the valve head 10 of the valve body 6 increases due to the increase in displacement of the valve body 6. As shown in Fig. 3, the first drain hole 4 is temporarily blocked, and the fluid pressure in the discharge side passage 1 is reduced. This causes it to rise rapidly. In this way, the fluid pressure in the discharge side passage 1 increases to the set value C (see Fig. 5). Light. ), the displacement of the valve body 6 further increases, as shown in FIG. The annular groove 8 of the valve body 6 comes to overlap the second drain hole 5, and The valve head 10 opens the first drain hole 4 and connects the first drain hole 4 and the second drain hole. Oil will now escape from both holes 5. As a result, the engine speed increases further. Even if the pressure rises, the liquid pressure in the discharge side passage 1 does not rise significantly.

[0014] The oil relief device of this embodiment drains as the engine speed increases. As the hole opening area increases step by step, the hydraulic pressure also increases, so the engine rotation range is low, it is possible to obtain a hydraulic pressure close to the low-pressure setting value A, and the engine speed increases. When the rotation speed is high, a hydraulic pressure close to the set value C on the high pressure side can be obtained. Also, When the liquid pressure in the discharge side passage 1 reaches the set value C, the first drain hole 4 and the second drain hole 5 open, the opening area doubles, and the increase in hydraulic pressure relative to the engine speed increases. Since the ratio decreases rapidly, even if the engine speed increases, the fluid pressure in the discharge passage 1 It won't get too big, and the load on the pump circuit can be kept to a minimum. .

[0015] In the embodiment described above, the drain is arranged along the axial direction of the valve housing chamber 2. Although two holes are provided, it is also possible to provide more drain holes.

[0016]

[Effect of the idea]

As explained above, the present invention has multiple drain holes along the axial direction of the valve housing chamber. The drain hole opens sequentially as the valve body slides as the engine speed increases. As a result, the opening area of the drain hole can be adjusted in stages according to the engine rotation range. This allows the desired hydraulic pressure to be obtained at all times.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is a sectional view of essential parts of the same embodiment.

FIG. 3 is a sectional view of essential parts of the same embodiment.

FIG. 4 is a sectional view of essential parts of the same embodiment.

FIG. 5 is a graph showing hydraulic pressure-engine rotation speed characteristics of the same example.

[Explanation of symbols]

1...Discharge side passage, 2...Valve accommodation chamber, 4...First drain hole,
5...Second drain hole, 6...Valve body.

Claims (1)

[Scope of utility model registration request] Claim 1: A drain hole is provided in a valve accommodating chamber communicating with a discharge side passage of a pump circuit, and a valve body that is biased in a direction to close the drain hole is slidably housed inside the valve chamber, and In an oil relief device in which a valve body slides against force to open a drain hole when the hydraulic pressure in a passage increases, a plurality of drain holes are arranged along the axial direction of a valve housing chamber. An oil relief device characterized by: