Patent Application
20170152962
The present invention relates to an oil pump control valve, and more particularly, an oil pump control valve that may control the oil pressure linearly by eliminating the residual pressure inside the valve and may be mounted outside a cylinder block to improve workability during maintenance.
The engine of an automobile is designed to circulate the oil for lubrication and cooling of various components mounted on the engine. Such an engine is provided with an oil pump for circulating the oil and a relief valve for preventing the oil pressure (hereinafter, referred to as “hydraulic pressure”) from being excessively raised by the oil pump.
Korean Patent Application Publication No. 2011-0056811 (May 31, 2011) discloses an oil pump including a relief valve 20.
Referring to
The oil pump 1 having the above-described structure is operated by a camshaft, and accordingly when the revolutions per minute (rpm) of the engine rises, the hydraulic pressure discharged from the oil pump 1 also rises. Accordingly, the hydraulic pressure circulated in the engine is not maintained to be constant, and lubrication and cooling of various parts such as the cylinder head and the cylinder block are not smoothly performed. In particular, excessive pressure is applied to various parts, thereby causing a significant decrease in durability.
The applicant filed an oil pump control valve (Korean Patent No. 1167505 (Jul. 16, 2011)), which is capable of maintaining a constant hydraulic pressure forcibly transported and discharged from the oil pump to the engine in order to solve the above problems.
The process of hydraulic pressure control by the conventional oil pump control valve will be described below.
When the solenoid is operated, the ball valve is lowered to open an inlet connected to an introduction port, the oil is introduced through the open inlet, and the introduced oil is controlled at a predetermined pressure and then discharged toward the engine through a control port. On the other hand, when the solenoid is stopped, the ball valve rises and closes the inlet, and the oil discharged toward the engine flows into the valve through the control port. At this time, the oil introduced into the valve when the solenoid is stopped is transported to the drain port through a space between a second valve seat and a rod.
Since the through-hole of the second valve seat has a diameter slightly larger than that of the rod so as to guide the movement of the rod, the amount of oil discharged to the space between the second valve seat and the rod is not so large. Therefore, a residual pressure always exists inside the valve, and the ball valve may not operate smoothly due to the residual pressure. In particular, if the operation of the ball valve is not smooth, the hydraulic pressure discharged toward the engine cannot be finely adjusted.
Further, the conventional oil pump control valve has a structure in which the drain port is located at the lower end of the valve. In order to mount the oil pump control valve having such a structure to the outside of the cylinder block, an oil passage needs to be formed at a position adjacent to the outer wall of the cylinder block. However, if the oil passage is positioned close to the outer wall, it is difficult to process the cylinder block, and the thickness of the corresponding portion becomes thin, resulting in poor durability and cracking due to hydraulic pressure.
It is an aspect of the present invention to provide an oil pump control valve capable of linearly controlling the pressure of the oil by eliminating the internal residual pressure of the valve and being able to be mounted outside the cylinder block to improve workability during maintenance.
In accordance with one aspect of the present invention, an oil pump control valve includes a valve for regulating an entry and exit of an oil and a solenoid for operating the valve.
The valve includes: a tubular holder including an introduction port formed at an upper end thereof, a control port formed at an upper portion of a middle part thereof and a discharge port formed at a lower portion of the middle part; a first valve installed inside the holder and positioned between the introduction port and the control port, the first valve including an inlet connected to the introduction port and a first outlet connected to the control port and formed at an upper end and lower end thereof; a ball valve movably installed inside the first valve seat to open or close the inlet; a second valve seat installed at a lower portion of the first valve seat and communicating with an interior of the first valve seat, the second valve seat being formed in a tube shape and provided at a middle part thereof with a second outlet connected to the discharge port; and a rod movably installed in the second valve seat and operated by the solenoid to move the ball valve, at least a portion of the rod is smaller than an inner diameter of the second valve seat
According to the above-described configuration, the oil transported to the engine side through the valve during operation of the solenoid flows back into the valve through the control port when the operation of the solenoid is stopped. At this time, since the ball valve is raised to close the inlet of the first valve seat, the introduced oil is discharged to the discharge port through the first valve seat, the second valve seat and the second outlet, and is then transported to the oil tank side.
The solenoid includes: a case coupled to surround one end of the holder and one end of the second valve seat and having an accommodation space therein; a bobbin installed in the accommodation space, the bobbin being in close contact with the flange and having a coil wound around an outer circumferential surface thereof; a guide installed inside the bobbin and having an upper end inserted into the second valve seat; a core coupled to a lower end of the bobbin and partially inserted into the guide; a plunger movably installed in the guide, a lower end of the rod being inserted thereinto; and a spring installed between the core to elastically support the plunger.
In the present invention configured as described above, the oil introduced through the control port when the operation of the solenoid is stopped is discharged to the oil tank side through the discharge port via the second valve seat and the rod. Therefore, a residual pressure will not occur in the valve. In addition, the operation failure due to the residual pressure may be solved, and the pressure of the oil discharged to the engine side may be linearly controlled.
Further, the present invention may easily form the oil passage of the cylinder block since the discharge port is formed in the middle part of the valve. In particular, since the oil pump control valve of the present invention can be mounted on the outside of the cylinder block, workability in maintenance may be improved, and manpower and cost required for the operation may be reduced.
Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings, wherein like reference numerals are used to refer to like elements throughout.
As shown in
The valve 100 includes a holder 110 inserted into the cylinder block (not shown) when the oil pump control valve is installed, a first valve seat 120 installed inside the holder 110, a ball valve 130 installed in the first valve seat 120, a second valve seat 140 provided at a lower portion of the first valve seat 120, and a rod 150 installed inside the second valve seat 140.
The holder 110 is formed in the shape of a hollow tube having a predetermined length. An introduction port 111 is formed on the top surface of the holder 110, and a control port 112 and a discharge port 113 are formed on an outer circumferential surface of the middle part of the holder 110. The introduction port 111 is a port through which oil supplied from an oil pump (not shown) is introduced, the control port 112 is a port through which the oil controlled to a predetermined pressure by the valve 100 is discharged to the engine side, and the discharge port 113 is a port through which the oil returned from the engine side is discharged to the oil tank side. The control port 112 is located at the upper portion of the middle part of the holder 110, and the discharge port 113 is located at the lower portion of the middle part of the holder 110.
Forming the discharge port 113 in the middle part of the holder 110 is intended to space the oil passage formed in the cylinder block (not shown) apart from the outer wall so as to improve workability and prevent breakage of the passage by hydraulic pressure. Positioning the discharge port 113 adjacent to the control port 112 is intended to facilitate discharge of the oil introduced through the control port 112 to the discharge port 113 to prevent a residual pressure from being formed in the value 100.
A partition 114 having a predetermined thickness is formed at an upper portion of the inner wall of the holder 110, more specifically, between the introduction port 111 and the control port 112. The partition 114 is provided with a mount hole 115 for installation of the first valve seat 120. In addition, a mount groove 116 for installing the second valve seat 140 is formed in the lower portion of the inner wall of the holder 110.
Filters 117a to 117c are provided in the introduction port 111, the control port 112, and the discharge port 113 to filter out foreign substances contained in the oil. The filter 117a provided in the introduction port 111 is a plate-shaped filter inserted into the upper end of the holder 110 and the filters 117b and 117c provided in the control port 112 and the discharge port 113 are annular filters surrounding the outer circumferential surface of the holder 110.
Meanwhile, an annular groove 118a is formed on the outer circumferential surface of the holder 110, and a ring-shaped O-ring 118b is provided in the groove 118a. The O-ring 118b serves to prevent the oil from leaking into a space between the oil pump control valve and the cylinder block (not shown). The O-ring 118b serves to prevent the oil introduced from the oil pump (not shown) or the engine (not shown) from abnormally flowing into the port other than the intended port. The groove 118a and the O-ring 118b are provided between the introduction port 111 and the control port 112, between the control port 112 and the discharge port 113, and between the discharge port 113 and the flange 119.
Referring to
As described above, the first valve seat 120 is installed to be inserted into the mount hole 115 of the partition 114, and a packing 126 is interposed between the first valve seat 120 and the partition 114. The packing 126 serves to prevent the oil from leaking into a space between the holder 110 and the first valve seat 120.
The ball valve 130 is movably installed in the operation space 124 of the first valve seat 120 to open or close the inlet 123. The ball valve 130 is formed in a completely spherical shape so as to reliably seal the inlet 123 upon contact with the first valve seat 120. A first seating groove 127 and a second seating groove 142 are formed at the lower end of the inlet 123 and the upper end of the protrusion 141 which come into contact with the ball valve 130 when the ball valve 130 moves.
As shown in
The internal space 146a to 146c of the second valve seat 140 is formed in a multi-step shape having a larger diameter toward the lower end. The upper end 146a of the internal space is a portion penetrated by the small-diameter portion 154 of the rod 150 and is formed to have a diameter larger than that of the small-diameter portion 154 such that the discharge passage 147 is provided between the upper end 146a and the small-diameter portion 154. The middle part 146b of the internal space serves to guide movement of the rod 150 and is formed in a diameter that allows the middle part to contact the large-diameter portion 152. The lower end 146c of the internal space is formed with a larger diameter than the middle part 146b, and the upper part of the guide 240, which will be described later, is inserted thereinto.
The lower end of the second valve seat 140, that is, the lower end provided with the flange 144 is positioned at an upper portion of the bobbin 220 serves as a yoke, which is a fixed iron core. When the lower end of the second valve seat 140 functions as a yoke, the magnetic force generated around the bobbin 220 may be strengthened to reliably control the movement of the plunger 260, which is a movable iron core.
The rod 150 is in the form of a multi-step rod including a large-diameter portion 152 contacting the second valve seat 140 and a small-diameter portion 154 spaced apart from the second valve seat 140. The lower end of the large-diameter portion 152 is inserted into the plunger 260 and moves together with the plunger 260 when the solenoid 200 is operated.
The solenoid 200 will be described with reference to
The solenoid 200 includes a case 210, a bobbin 220 installed inside the case 210, a coil 230 wound around the outer circumferential surface of the bobbin 220, a guide 240 inserted into the bobbin 220, a core 250 coupled to the lower end of the bobbin 220, a plunger 260 movably installed inside the guide 240, and a spring 270 installed between the core 250 and the plunger 260.
The case 210 has a cup shape with an open top and a closed bottom. A housing space 212 is defined in the case 210. The bobbin 220, the coil 230, the guide 240, the core 250, the plunger 260, and the spring 270 are installed in the case 210. At this time, the upper end of the case 210 is caulked so as to surround the lower end of the holder 110. When the upper end of the case 210 is caulked, the valve 100 is pressed against the solenoid 200 to closely contact the components 220 to 270 installed inside the case 210. Therefore, it is possible to prevent the components 220 to 270 installed inside the case 210 from moving and to prevent foreign substances from flowing into the upper portion of the case 210.
The bobbin 220 is in the form of a hollow spool having flanges formed at the upper and lower ends thereof. The second valve seat 140 is positioned at the upper portion of the bobbin 220, the core 250 is coupled to the lower portion of the bobbin 220, and the coil 230 for generating a magnetic field is wound around the outer circumferential surface of the bobbin 220. The bobbin 220 is made of an insulator so as to electrically isolate the coil 230 from the core 250 and the plunger 260. In this case, the second valve seat 140 positioned at the upper portion of the bobbin 220 may serve as a fixed iron core together with the core 250.
The coil 230 is a conductive wire for generating a magnetic field around the bobbin 220 when power is applied thereto. The coil 230 is closely and uniformly wound around the outer circumferential surface of the bobbin 220 to form a cylindrical shape. The magnetic field generated in the coil 230 when power is applied is induced by the core 250 to lower the plunger 260. At this time, the intensity of the magnetic field is proportional to the intensity of the current flowing along the coil 230 and the number of the coils 230 wound around the bobbin 220. Therefore, as a strong current flows along the coil 230 or the number of windings of the coil 230 increases, the magnetic field becomes strong, ensuring that the movement of the plunger 260 is reliably controlled.
The guide 240 has a shape of a tube with a predetermined length and is inserted into the bobbin 220 in a penetrating manner The upper portion of the guide 240 protrudes through the bobbin 220 and is inserted into the lower end 146c of the internal space provided in the second valve seat 140. The guide 240 guides the movement of the plunger 260 and prevents an external force from deforming the solenoid 200.
The core 250 is a fixed iron core for moving the plunger 260, which is a movable iron core, when power is applied. The core 250 is formed in a multi-step disc shape, and coupled to the bobbin 220 such that a part of the core 250 is inserted into the bobbin 220. As shown in
The plunger 260 is a metal rod that is moved up and down inside the bobbin 220 by a magnetic field generated by the coil 230. The large-diameter portion 152 of the rod 150 is inserted into the upper surface of the plunger 260 and a movement groove 262 is formed in the outer circumferential surface of the plunger 260. The movement groove 262 is provided to minimize the operation resistance of the plunger 260 and functions as a passage through which the fluid filling the guide 240 is transported when the plunger 260 moves.
The spring 270 is a typical coil spring and elastically supports the plunger 260 upward. That is, the spring 270 elastically supports the plunger 260 upward to maintain the ball valve 130 at an elevated position in normal times when power is not applied to the solenoid 200.
Hereinafter, operation of the oil pump control valve according to the present embodiment will be described with reference to
As shown in
On the other hand, when the ball valve 130 rises and is seated in the first seating groove 127, the discharge passage 147 is opened. Thereby, the oil R discharged from the control port 112 flows back through the control port 112 and is introduced into the first valve seat 120 through the first outlet 125. The introduced oil R is transported to the second valve seat 140 through the discharge passage 147 and then discharged to the outside through the discharge port 113 via the second outlet 143.
While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, those skilled in the art will appreciate that the invention is not limited to the disclosed exemplary embodiments, but is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. Therefore, the scope of the present invention should be construed as being covered by the scope of the appended claims, rather than the specific embodiments, and all technical ideas falling within the scope of the claims should be construed as being included in the scope of the present invention.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10-2014-0082974 | Jul 2014 | KR | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/KR2015/006653 | 6/29/2015 | WO | 00 |
