JPH0835431A - Supercharger of engine - Google Patents

Abstract

PURPOSE:To effectively decrease the agitation resistance of a hydraulic turbine in a turbine chamber just after the assisted driving state is switched to the non assisted driving state. CONSTITUTION:In the specific operating range, operating oil is forcibly fed into a turbine chamber 41 from a variable displacement oil pump 108 through an operating oil supplying port 62, so as to be injected to a hydraulic turbine 43, thereby a turbo rotary shaft 36 on which the hydraulic turbine 43 18 provided is assisted-driven. Just after the assisting operation is stopped, the operating oil feeding direction by the variable displacement oil pump 108 is reversed, so as to suck operating oil in the turbine chamber 41 by the variable displacement oil pump 108.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a supercharger for an engine equipped with a turbocharger.

[0002]

2. Description of the Related Art In a conventional supercharger, a hydraulic turbine is mounted on a turbo rotary shaft connecting a compressor wheel and a turbine wheel, as disclosed in, for example, Japanese Patent Publication No. 59-51649. Is stored in a turbine chamber formed in the turbocharger, and hydraulic oil is pumped into the turbine chamber by an oil pump to inject it into the hydraulic turbine, thereby auxiliary driving the turbo rotary shaft to drive the turbocharger. It is known that the output is increased. With such a device, it is possible to obtain a sufficient supercharging pressure by the above-mentioned auxiliary drive even in a state where the exhaust energy is not sufficiently increased such as during low-speed high-load operation, and then the exhaust energy is sufficiently increased. By stopping the auxiliary drive in this state and performing supercharging with exhaust energy as in a normal turbocharger, fuel consumption can be saved.

Further, the above-mentioned publication also describes that the working oil injected into the turbine chamber is recovered and reused (that is, the working oil is circulated).
It has become possible to further reduce fuel consumption by reducing the supplementary amount of hydraulic oil for auxiliary drive.

[0004]

In the above apparatus, the hydraulic oil existing in the turbine chamber immediately after switching from the auxiliary drive state to the auxiliary drive stop state (that is, a state in which the turbo rotary shaft is driven exclusively by exhaust energy). As a result, the hydraulic turbine receives agitation resistance from the hydraulic turbine, which reduces the rotational speed of the turbo rotary shaft as compared with a normal turbocharger that does not perform auxiliary drive, and the agitation may cause the hydraulic oil temperature to rise excessively. is there. In particular, in a device that reuses hydraulic oil as described in the above publication (that is, circulates between the oil pump and the turbine chamber), the turbine chamber must be filled with the hydraulic oil. It will be very large.

In the turbocharger disclosed in the above publication, immediately after the auxiliary drive is stopped, it is possible to allow the working oil in the turbine chamber to escape to the outside of the turbine chamber to some extent from the gap between the turbo rotating shaft and the bearing that supports the shaft. However, it is difficult to discharge the hydraulic oil in the turbine chamber at a speed sufficient to avoid the stirring resistance. Further, if the gap is set to be large in order to increase the discharging speed, the turbo rotary shaft may be considerably rattled, and seizure or the like may occur. Moreover, in the device for circulating the hydraulic oil as described in the above publication, if the gap is increased as described above, the amount of the hydraulic oil leaking from the gap to the outside of the turbine chamber during the auxiliary drive increases. There is also an inconvenience that the amount of fuel that must be replenished in the circulation path increases, the engine load due to the drive of a pump or the like for performing this replenishment increases, and fuel consumption deteriorates.

In view of the above circumstances, the present invention provides a supercharging device for an engine in which a turbocharger is switched between an auxiliary driving state and a non-auxiliary driving state using a hydraulic turbine. An object of the present invention is to effectively reduce stirring resistance of a hydraulic turbine in a turbine chamber immediately after switching to a drive state.

[0007]

As a means for solving the above problems, the present invention provides a hydraulic turbine on a turbo rotary shaft that connects a compressor and a turbine in a turbocharger and stores the hydraulic turbine. An auxiliary drive pump that auxiliary-drives the turbo rotary shaft by pumping hydraulic oil to the turbine chamber and injecting the hydraulic oil into the hydraulic turbine; and a state and an auxiliary drive pump that drives the turbo rotary shaft depending on the operating state of the engine. In a supercharging device for an engine, comprising: a drive control means for switching the auxiliary drive pump to a non-driven state, a suction pump for sucking hydraulic oil in the turbine chamber to the outside of the turbine chamber, and at least the auxiliary drive pump in an auxiliary drive state. And a suction control means for operating the suction pump immediately after being switched to the non-auxiliary drive state. Than it (claim 1).

In this device, it is more preferable to form a circulation passage for circulating the working oil between the turbine chamber and the auxiliary drive pump (claim 2).

If a single oil pump is used as both the auxiliary drive pump and the suction pump, more excellent effects as described below can be obtained (claim 3).

More specifically, as the oil pump, a vaned rotor is housed in an oscillating cam ring, and the eccentric direction and the eccentric amount of the cam ring with respect to the rotor are changed to change the discharge direction and discharge amount of the hydraulic oil. Or a variable capacity vane pump that changes, and the drive control means and the suction control means are configured to change the eccentric state of the cam ring according to the operating state of the engine (claim 4), or as the oil pump, A device in which the discharge direction changes depending on whether the rotational operation direction is normal or reverse, and the drive control means and the suction control means are configured to rotate the oil pump forward or reverse in accordance with the operating state of the engine (claim 5). Are preferred.

In this device, a circulation passage for circulating the working oil between the turbine chamber and the oil pump is formed, and in the circulation passage, the suction port of the oil pump and the turbine chamber during auxiliary driving are formed. A check valve that allows the flow of hydraulic oil only in the direction from the turbine chamber to the oil pump suction port is provided between the check chamber and the oil pump suction port. It is more preferable that the recovery oil recovery passage is connected (Claim 6).

Further, a replenishing pump for replenishing the working oil in the circulation passage is provided, and the flow of the working oil is provided in the middle of the working oil collecting passage only when the primary pressure in the working oil collecting direction is above a certain level. It is further preferable to provide an allowable pressure regulator (Claim 7).

Further, the hydraulic oil supply portion for the turbine chamber may be formed upward below the turbine chamber (claim 8), or the oil pump may be connected to the engine output shaft so as to be always interlocked with the oil pump. By configuring the drive control means and the suction control means so as to increase the discharge capacity of the oil pump as the engine speed increases in the operating region in which the engine is operated in the direction of sucking the hydraulic oil from the turbine chamber ( According to claim 9), more excellent effects as described later can be obtained.

[0014]

According to the apparatus of claim 1, immediately after the auxiliary drive pump is switched from the auxiliary drive state to the non-auxiliary drive state, the suction pump operates to positively suck the hydraulic oil in the turbine chamber. In this turbine chamber, the stirring resistance that the hydraulic turbine for auxiliary drive receives from the hydraulic oil rapidly decreases. Moreover, since it is not necessary to increase the clearance between the turbo rotary shaft and the bearing as in the conventional case, rattling and the like at the time of rotation of the turbo rotary shaft can be suppressed.

According to the second aspect of the present invention, since the working oil is circulated between the turbine chamber and the auxiliary drive pump, the auxiliary drive for constantly injecting the working oil into the hydraulic turbine. Pump load is low. Moreover, since it is not necessary to increase the clearance between the turbo rotary shaft and the bearing as described above, the amount of this hydraulic oil leaking out of the turbine chamber from the above clearance during the circulation of the hydraulic oil is small, and therefore the operation during the circulation is performed. It also reduces the amount of oil that needs to be replenished.

Further, in the apparatus according to the third aspect, both the auxiliary drive and the suction of the working oil from the turbine chamber are performed by a single oil pump.

More specifically, in the apparatus according to claim 4,
In a variable displacement vane pump having a vane rotor housed in an oscillating cam ring, by changing the eccentric direction of the cam ring, switching between the auxiliary drive and suction of hydraulic oil from the turbine chamber is performed, and The pump displacement is adjusted by changing the eccentricity of the cam ring.

On the other hand, in the apparatus according to the fifth aspect, the auxiliary drive and the suction of the hydraulic oil from the turbine chamber are switched by switching the rotational operation direction of the oil pump between the forward and reverse directions.

According to a sixth aspect of the present invention, as in the second aspect of the present invention, the operating oil circulates between the turbine chamber and the auxiliary drive pump, so that an oil pump for injecting the operating oil is provided. The load is reduced. Moreover, there is a check valve in the circulation passage between the suction port of the oil pump and the turbine chamber during the auxiliary drive, which allows the flow of the working oil only in the direction from the turbine chamber to the oil pump suction port. Since the recovery passage for the hydraulic oil from the turbine chamber is connected between the check valve and the oil pump suction port, the hydraulic oil flows backward through the circulation passage when the oil pump operates in the suction direction. Is prevented, and this hydraulic oil is recovered through the recovery passage.

Here, in the apparatus according to the seventh aspect, the circulation passage is replenished with the working oil by the replenishing pump, and the pressure regulator provided in the middle of the working oil recovery passage is used during the auxiliary driving. The primary pressure of the oil pump is maintained at an appropriate pressure, and the hydraulic oil is prevented from being unnecessarily released from the recovery passage. Moreover, during suction, the suction regulator (the discharge pressure of the oil pump) opens the pressure regulator, and the working oil is recovered through the working oil recovery passage without any inconvenience.

In the apparatus according to the eighth aspect, since the working oil supply portion to the turbine chamber is formed upward below the turbine chamber, the working oil in the turbine chamber is also utilized by its own weight at the time of suction. It is efficiently sucked from the bottom side through the hydraulic oil supply section.

In each of the above-mentioned devices, when the oil pump is connected to the engine output shaft and is always interlocked, the pump rotation speed increases as the engine rotation speed increases, and the heating degree of the pump due to friction resistance increases. In the device according to claim 9, the discharge capacity of the oil pump increases as the engine speed increases in the operating region where the oil pump operates as a suction pump (that is, the amount of scavenging oil or the amount of scavenging by the pump is increased. By this, the cooling action of the pump by this scavenging oil or the scavenged hydraulic oil or air is enhanced, and an excessive temperature rise of the pump is prevented. Moreover, the discharge capacity is suppressed at low speed when cooling is less required, and fuel consumption is reduced.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to FIGS.

A common intake pipe 14 is connected to each cylinder of the engine 10 shown in FIG. 2 through an intake manifold 12, and a throttle valve 15 and an intercooler 16 are provided in the middle of the common intake pipe 14 from a side closer to the intake manifold 12. A turbocharger 24, an air cleaner 18, and the like are provided.
A common exhaust pipe 20 is connected to each of the cylinders via an exhaust manifold 19, and the turbocharger 24, the exhaust gas purifying catalyst 22 and the like are provided in the middle thereof.

The internal structure of the turbocharger 24 is shown in FIG. The turbocharger 24 includes a compressor 26 and a turbine 28, which are interconnected via a turbo rotating shaft 36. The compressor 26 is housed in the compressor housing 30, and the turbine 28 is housed in the turbine housing 32. The compressor housing 30 is installed in the middle of the common intake pipe 14, and the turbine housing 32 is installed in the middle of the common exhaust pipe 20. Has been. Both housings 30 and 32 are connected via a substantially cylindrical main body housing 34. A cylindrical bearing housing 40 is loaded inside the main body housing 34, and the turbo rotary shaft 36 is rotatably supported inside the inner housing 40 via a bearing 42.

At the substantially central portion of the turbo rotary shaft 36,
A hydraulic turbine 43 is formed. In this embodiment, the hydraulic turbine 43 is formed in the shape of a Pelton wheel, and is configured so as to be rotationally driven integrally with the turbo rotary shaft 36 by spraying hydraulic oil from the predetermined direction on the outer peripheral portion thereof. .

Next, the oil passage (distribution passage) of the working oil formed in the turbocharger 24 will be described. In this embodiment, the working oil and the lubricating oil for the bearing 42 are commonly used.

A single hydraulic oil supply port 62 is formed on the bottom wall of the main body housing 34, and a hydraulic oil supply pipe 61 is connected to the hydraulic oil supply port 62. A ring-shaped oil jet case 44 is loaded in a position surrounding the hydraulic turbine 43 in the bearing housing 40, and a turbine chamber 41 for housing the hydraulic turbine 43 is formed inside the oil jet case 44. . A groove 45 is formed around the entire circumference of the oil jet case 44, and a large number of nozzle holes 63 that connect the groove 45 and the turbine chamber 41 are arranged side by side along the entire circumference of the oil jet case 44. , The groove 4
The hydraulic oil supply port 62 is open at 5. The direction of each nozzle hole 63 is set such that the hydraulic oil sprayed from these nozzle holes 63 is sprayed onto the outer peripheral portion of the hydraulic turbine 43, whereby the hydraulic turbine 43 is rotationally driven. A hydraulic oil discharge port 86 is provided on the top wall of the main body housing 34, and a communication passage 46 that connects the hydraulic oil discharge port 86 and the inside of the turbine chamber 41 is provided with the bearing housing 40 and the main body housing 34.
It is formed on the top wall.

Reference numeral 47 in FIG. 3 denotes a lubricating oil passage for supplying the working oil as lubricating oil to the periphery of the turbo rotary shaft 36.

Next, the flow path of the hydraulic oil will be described with reference to FIG.

The hydraulic oil supply port 62 is connected to the discharge port of the variable capacity oil pump 108 via the hydraulic oil supply pipe 61, and the suction port of the variable capacity oil pump 108 is routed through the circulation pipe 50. Is connected to the hydraulic oil discharge port 86, and a hydraulic oil circulation passage is formed by the hydraulic oil supply pipe 61 and the hydraulic oil discharge port 86.

In the circulation pipe 50, check valves 52 and 54 are provided at a position near the hydraulic oil discharge port 86 and a position near the suction port of the variable displacement oil pump 108, respectively. These check valves 5
2 allows the flow of the hydraulic oil only in the direction from the hydraulic oil discharge port 86 toward the variable displacement oil pump 108, and these allow the reverse flow of the hydraulic oil in the circulation passage (that is, the variable displacement oil pump). Flow in the direction from 108 to the hydraulic oil discharge port 86) is prevented.

One end of a hydraulic oil recovery pipe 56 is connected to a position between the check valve 54 and the variable displacement oil pump 108 in the circulation pipe 50, and the other end is led to an oil pan 55. A pressure regulator 58 is provided between the hydraulic oil recovery pipes 56.
The pressure regulator 58 is used for the oil pan 5 described above.
5 when the flow of hydraulic oil from the direction toward the circulation pipe 50 is blocked, and the primary pressure in the direction from the circulation pipe 50 toward the oil pan 55 (that is, the pressure on the circulation pipe 50 side) is above a certain level. It is configured to allow the flow of hydraulic oil only.

In the turbine chamber 41, a return pipe 68 for returning the leakage of the lubricating oil and the hydraulic oil for auxiliary drive to the oil pan 55 is connected, and the lubricating oil passage 47 and the engine shown in FIG. 3 are connected. Lubricating pipes 6 on the lubricated parts of each part
0 is connected. A low-pressure oil pump (replenishing pump) 64 is installed in the lubrication pipe 60 and the circulation pipe 50.
Of the low-pressure oil pump 64 is connected to the inside of the oil pan 55 through the oil cleaner 66. The operation of the low-pressure oil pump 64 causes the oil in the oil pan 55 to operate properly. Oil or lubricating oil is replenished in the circulation pipe 50 and the lubrication pipe 60.

Next, the variable displacement oil pump 108 described above.
The structure will be described with reference to FIGS.

In the housing 70 of the variable displacement oil pump 108, a cam ring 72 is swingably housed around an upper pin 71 and a rotor 73 is rotatably supported around a point O _1. The rotor 73 is housed inside the cam ring 72. A plurality of (eight in the illustrated example) vanes 74 are housed in the outer peripheral portion of the rotor 73 so as to be movable in the radial direction, and each vane 74 is urged radially outward by means (not shown). The vane 74 and the rotor 73 rotate integrally while the tip of the slide member 74 slidably contacts the inner peripheral surface of the cam ring 72. In addition, the housing 70
Has a suction groove 75 formed in the upper side wall thereof and a discharge groove 76 formed in the lower side wall thereof. The circulation pipe 50 is connected to the suction groove 75 and the hydraulic oil supply pipe 61 is connected to the discharge groove 76.
Is connected.

From the lower end of the cam ring 72, the lever 7
7 extends downward, and an end portion of the lever 77 is connected to an output shaft 79 of a stepping motor 80 via a pin 78. The stepping motor 80 includes a rotating portion that is rotated by receiving a control pulse signal,
A conversion mechanism that converts the rotation of the rotating portion into the axial operation of the output shaft 79 is built in, and the cam ring 72 swings around the pin 71 with the axial operation of the output shaft 79. Thus the inner peripheral surface center of the cam ring 72 to the rotor rotational center O ₁ (hereinafter, referred to as the cam ring center.) eccentric direction and the eccentric amount e of O ₂ is made to vary.

On the other hand, the rotating shaft of the rotor 73 is connected to the crankshaft 102 of the engine 10 via the drive transmission mechanism 104 shown in FIG. As shown in Fig. 4, the device rotates in the counterclockwise direction. When the cam ring center O ₂ is eccentric to the rotor rotation center O ₁ in the left direction in FIG. 4 when the rotor rotates in this direction, the hydraulic oil flows from the suction groove 75 to the cam ring 7 as shown in FIG.
2 is sucked into the working chamber and discharged from the discharge groove 76, and as shown in FIG. 5, the cam ring center O ₂ and the rotor rotation center O ₁
When and are in agreement, the suction and discharge of hydraulic oil are not performed, and as shown in FIG. 6, when the cam ring center O ₂ is eccentric to the rotor rotation center O ₁ in the right direction in the figure, The hydraulic oil is sucked into the working chamber in the cam ring 72 from the discharge groove 76 and discharged from the suction groove 75, and the discharge capacity increases as the eccentricity e increases.

As shown in FIG. 4, this engine includes a throttle sensor 112 for detecting the throttle opening of the throttle valve 15, an engine speed sensor 114 for detecting the engine speed, and an engine intake pipe for detecting the intake pipe internal pressure. A boost sensor 116 and the like are provided, and these sensors are connected to an ECU (control unit; drive control means and suction control means) 120. This ECU
Reference numeral 120 stores a map regarding the target boost pressure Po as shown in FIG. 7A and a map regarding the basic discharge amount qo of the variable displacement oil pump as shown in FIG. 7B, and these maps are stored. And based on the detection signal of each sensor,
The operation control of the stepping motor 80 is performed.

In the basic discharge amount qo set in FIG. 7 (b), for example, "100%" means that the cam ring 72 is sucked from the suction groove 75 and discharged from the discharge groove 76 as shown in FIG. Means the discharge amount when the ink is swung to the limit, and “−20%” means the discharge groove 76 as shown in FIG.
It means 20% of the discharge amount when the cam ring 72 is rocked to the limit in the direction of sucking from and discharging from the suction groove 75.

Next, the control operation performed by the ECU 120 will be described.

The ECU 120 reads the detection signals for the intake negative pressure, the engine speed, the throttle opening, etc. (step S1 in FIG. 8), and the read operating condition of the engine and the map shown in FIG. 7 (b). Based on the basic discharge amount qo determined based on the target discharge amount q, the displacement control of the variable displacement oil pump 108, that is, the operation control of the stepping motor 80 is performed (step S2). Furthermore, FIG.
The target supercharging pressure Po obtained from the map shown in (a) is compared with the actual supercharging pressure P obtained from the detection signal (step S3), and this supercharging pressure P is the target supercharging pressure Po.
If it is lower than (YES in step S3), the target discharge amount q is changed from the basic discharge amount qo to the basic discharge amount q.
If the supercharging pressure is equal to or higher than the target supercharging pressure Po (NO in step S3), the target discharge is changed to a value obtained by adding a correction constant q ₁ (> 0) to o (step S4). Correction is performed to change the amount q to a value obtained by subtracting the correction constant q ₁ from the basic discharge amount qo.

Here, as shown in FIG. 7 (b), the basic discharge amount qo is set to a positive value in a region where the engine speed is low, that is, in a region where exhaust energy is low, and therefore, the ECU 120 in FIG. As shown, the variable displacement oil pump 108 is switched to a state in which the hydraulic oil is sucked from the suction groove 75 and discharged from the discharge groove 76. Therefore, the high-pressure hydraulic oil discharged from the variable displacement oil pump 108 passes through the hydraulic oil supply port 62 and the groove 45 of the oil jet case 44 shown in FIG. The turbocharger shaft 36 is jetted toward the blades, whereby the turbo rotary shaft 36 is assisted and the boost pressure is increased.
The injected hydraulic oil fills the turbine chamber 41, and the excess oil is discharged from the hydraulic oil discharge port 86 and returned to the suction side of the variable displacement oil pump 108 through the circulation pipe 50. Such a circulation of hydraulic oil reduces the load on the variable displacement oil pump 108 and saves fuel consumption.

When the engine speed increases from this state and the basic discharge amount qo shown in FIG. 7 (b) shifts to the region of 0 or minus, not only the auxiliary drive is stopped but also the ECU 120 immediately after the shift. Only exceptionally, Figure 9
Change the oil pump capacity to the minus side at once. That is, the cam ring 72 of the variable displacement oil pump 108 is rapidly switched from the position shown in FIG. 4 to the position shown in FIG.

As a result, the variable displacement oil pump 10
The reference numeral 8 sucks the hydraulic oil filled in the turbine chamber 41 from the hydraulic oil supply port 62 in the opposite direction, and opens the pressure regulator 58 by its discharge pressure to open the hydraulic oil to the hydraulic oil recovery pipe 5.
Return to the oil pan 55 through 6. Due to such suction, the hydraulic oil is quickly discharged from the turbine chamber 41, and thus the stirring resistance that the hydraulic turbine 43 receives from the hydraulic oil in the turbine chamber 41 is significantly reduced. Such suction is performed only for the period t1 (FIG. 9) and the turbine chamber 41
After quickly draining the hydraulic oil from the inside, the oil pump capacity is returned to the basic discharge amount qo, and the normal state is restored.

As described above, in this apparatus, immediately after the auxiliary drive by the variable displacement oil pump 108 is stopped, the variable displacement oil pump 108 is reversely sucked to quickly supply the working oil from the turbine chamber 41. Since the oil is discharged, the stirring resistance of the hydraulic turbine 43 can be effectively reduced, and accordingly, a high turbo rotation speed can be secured with less fuel consumption, and the temperature rise of the oil due to the stirring can be suppressed. it can.

Further, since it is not necessary to drain the hydraulic oil in the turbine chamber 41 from the gap between the turbo rotary shaft 36 and the bearing 42 as in the conventional case, it is not necessary to make the gap particularly large. No significant rattling of 36 occurs. In particular, in the case of the device for circulating the hydraulic oil as shown in FIG. 1, if the clearance is increased, the amount of the hydraulic oil that escapes from the circulating oil passage also increases, so that the low pressure oil flows through the circulating oil passage during auxiliary drive. Although the amount of hydraulic oil supplied through the pump 64 is increased, the leakage amount is extremely small in the device of the present embodiment, and therefore the leak amount is extremely small. Therefore, the load of the low-pressure oil pump 64 can be further reduced. it can.

Further, the following effects can be obtained in this embodiment.

(A) As the variable displacement oil pump 108, the one in which the vane rotor 73 is housed in the cam ring 72 is used, and therefore the variable displacement oil pump is simply changed by changing the eccentric direction of the cam ring 72. 10
8 can be easily switched between the auxiliary drive state and the suction state, and the structure is simplified.

However, even if such a cam ring type oil pump is not used, it is possible to use a single oil pump for both auxiliary drive and suction by switching the rotational operation direction of the rotor between forward and reverse. Is.

(B) Check valve 5 is provided in the middle of the circulating oil passage.
Since 2, 54 are provided, it is possible to reliably prevent the hydraulic oil from flowing backward through the circulating oil passage when the variable displacement oil pump 108 sucks the oil. Moreover, the above check valve 5
4 is connected to the variable displacement oil pump 108, the sucked hydraulic oil can be reliably guided to the hydraulic oil recovery pipe 56 side. A pressure regulator 58 that allows the flow of hydraulic oil in the recovery direction is provided in the middle of the hydraulic oil recovery pipe 56 only when the primary pressure is equal to or higher than a certain level. The primary pressure of the oil pump can be maintained at an appropriate pressure, and the hydraulic oil can be prevented from being unnecessarily released to the hydraulic oil recovery pipe 56 side during auxiliary driving.

(C) Connect the hydraulic oil supply port 62 to the turbine chamber 4
Since it is provided below 1 above, the hydraulic oil in the turbine chamber 41 can be efficiently discharged from below through the hydraulic oil supply port 62 by utilizing its own weight during suction.

(D) In the case of a device in which the variable displacement oil pump 108 is connected to the engine output shaft 102 and is always interlocked as in the above-described embodiment, particularly in a high rotation region (that is, the variable displacement oil pump 108 serves as a suction pump). In the operating region where the engine operates, the pump rotational speed increases as the engine rotational speed increases, and the heating degree of the pump increases due to frictional resistance. However, as shown in FIG. 7, the variable displacement oil pump increases as the engine rotational speed increases. If the discharge capacity of the suction side of 108 is increased, that is, the scavenging amount by the variable displacement oil pump 108 (the scavenging amount after the hydraulic oil is completely collected) is increased, low rotation at a low rotation speed of the pump is reduced. Occasionally, the discharge capacity is suppressed to reduce fuel consumption, and at the time of high rotation, the cooling action of the pump by the oil or the hydraulic oil or air that is scavenged is increased. It is possible to prevent excessive temperature rise of the pump.

In the above embodiment, the single variable displacement oil pump 108 is also used as the auxiliary drive pump and the suction pump. However, the variable displacement oil pump 108 is exclusively used for the auxiliary drive as the suction pump. May be installed separately. In this case, for example, suction may be performed by the suction pump from a position different from the hydraulic oil supply port 62 and the hydraulic oil discharge port 86. However, as in the above embodiment, the variable displacement oil pump 108 is
If it is also used, the entire device can be further simplified, and the weight, size and cost of the vehicle can be reduced.

Further, in the present invention, the operating region in which the auxiliary driving is performed and the operating region in which the auxiliary driving is stopped may be set freely, and in any setting, when the auxiliary driving state is switched to the non-auxiliary driving state. By performing the suction, it is possible to obtain the effect of reducing the stirring resistance.

[0056]

As described above, the present invention is an apparatus for auxiliary driving a turbo rotary shaft by pumping hydraulic fluid to a turbine chamber by an auxiliary driving pump and injecting it into a hydraulic turbine. Immediately after switching from the driving state to the non-auxiliary driving state, the suction pump sucks the working oil in the turbine chamber. It is possible to effectively reduce the stirring resistance that the hydraulic turbine receives from the hydraulic oil. Therefore, there is an effect that the rotational speed of the turbo rotary shaft can be kept high with low fuel consumption and that the temperature of the oil due to the agitation can be prevented.

Here, in the apparatus according to the second aspect of the present invention, since the working oil is circulated between the turbine chamber and the auxiliary drive pump, the auxiliary drive pump for constantly injecting this working oil into the hydraulic turbine is used. The load can be reduced, and the fuel consumption can be improved accordingly. Moreover, unlike the conventional one in which the hydraulic oil is released from the gap between the turbo rotary shaft and the bearing, it is not necessary to increase the above gap,
The amount of the hydraulic oil leaking from the gap or the like to the outside of the turbine chamber during the circulation of the hydraulic oil is small, and thus the amount of the hydraulic oil that needs to be replenished during the circulation is also small, so that the fuel efficiency can be further improved.

In the apparatus according to the third aspect of the present invention, since a single oil pump is used as both the auxiliary drive oil pump and the suction pump, the entire apparatus is significantly larger than the case where both pumps are installed separately. Moreover, there is an effect that it can be reduced in size, weight and cost.

More specifically, in the apparatus according to claim 4,
In a variable displacement vane pump in which a rotor with vanes is housed in a swingable cam ring, the auxiliary drive and suction of hydraulic oil from the turbine chamber are switched by changing the eccentric direction of the cam ring. Therefore, it is possible to smoothly perform the combined use of the oil pump as the auxiliary drive pump and the suction pump by a simple operation of swinging the cam ring.

On the other hand, in the apparatus according to the fifth aspect, the dual function can be achieved by switching the rotation operation direction of the oil pump between forward and reverse.

According to a sixth aspect of the present invention, similarly to the second aspect of the present invention, the operating oil is circulated between the turbine chamber and the auxiliary drive pump, so that an oil pump for injecting the operating oil is provided. The load can be reduced. In addition, a check valve is provided at a position between the suction port of the oil pump and the turbine chamber during the auxiliary drive in the circulation passage to allow the flow of the working oil only in the direction from the turbine chamber to the suction port of the oil pump. Since the recovery passage for the working oil from the turbine chamber is connected to a position between the check valve and the oil pump suction port, the working oil flows backward through the circulation passage when the oil pump operates in the suction direction. In addition to preventing the above, the suctioned operating oil can be reliably guided to the recovery passage side.

Further, in the apparatus according to the seventh aspect, a replenishing pump for replenishing the working oil in the circulation passage is provided, and the primary side pressure in the working oil collecting direction is equal to or higher than a certain level in the middle of the working oil collecting passage. In this case, since a pressure regulator that allows the flow of hydraulic oil is provided, the hydraulic regulator wastefully releases the hydraulic oil from the recovery passage while maintaining the primary pressure of the oil pump during the auxiliary drive at an appropriate pressure. In addition, it is possible to prevent the above from occurring, and at the time of suction, there is an effect that the pressure regulator is automatically opened by the suction pressure (the discharge pressure of the oil pump) and the hydraulic oil can be recovered through the hydraulic oil recovery passage without any inconvenience. .

According to the eighth aspect of the present invention, since the hydraulic oil supply portion to the turbine chamber is formed upward below the turbine chamber, immediately after the switching from the auxiliary drive state to the non-auxiliary drive state, the turbine chamber is immediately opened. There is an effect that the operating oil can be efficiently sucked from the bottom side through the operating oil supply section while utilizing its own weight.

In each of the above-mentioned devices, when the oil pump is connected to the engine output shaft and is always linked, the pump rotation speed increases as the engine rotation speed increases, and the heating degree of the pump increases due to frictional resistance. In the device according to claim 9, in the operating region where the oil pump operates as a suction pump, the discharge capacity of the oil pump increases as the engine speed increases (that is, the amount of scavenging oil or the amount of scavenging by the pump increases. ), The discharge capacity is suppressed at low speed when pump cooling is less necessary and fuel consumption is saved, while at the time of high speed the cooling effect of the pump by the above-mentioned scavenging oil or scavenged hydraulic oil or air is increased. The effect is to prevent excessive temperature rise of the pump.

[Brief description of drawings]

FIG. 1 is a diagram showing an oil circulation system in an embodiment of the present invention.

FIG. 2 is an overall configuration diagram of an engine in the above embodiment.

FIG. 3 is a sectional view of the turbocharger in the above embodiment.

FIG. 4 is a cross-sectional view showing how the variable displacement oil pump for auxiliary driving of the turbocharger is switched to the auxiliary driving state in the above embodiment.

FIG. 5 is a cross-sectional view showing a state in which the variable displacement oil pump is switched to a non-discharging state.

FIG. 6 is a cross-sectional view showing a state where the variable displacement oil pump is switched to a suction state.

FIG. 7A is a diagram showing a map relating to a target supercharging pressure stored in an ECU in the above embodiment, and FIG. 7B is a diagram showing a map relating to a basic discharge amount stored in the ECU. is there.

FIG. 8 is a flowchart showing an arithmetic control operation performed by the ECU.

FIG. 9 is a graph showing a change over time in an oil pump capacity controlled by the ECU.

[Explanation of symbols]

 10 Engine Body 24 Turbocharger 26 Compressor 28 Turbine 36 Turbo Rotating Shaft 41 Turbine Chamber 43 Hydraulic Turbine 50 Circulation Pipe 52, 54 Check Valve 56 Hydraulic Oil Recovery Pipe 58 Pressure Regulator 62 Hydraulic Oil Supply Port 64 Low Pressure Oil Pump (Replenishment) 72 cam ring 73 rotor 74 vane 75 suction groove 76 discharge groove 80 stepping motor 102 engine output shaft 108 variable displacement oil pump 120 ECU (drive control means and suction control means)

Claims (9)

[Claims] 1. A turbo supercharger is provided with a hydraulic turbine on a turbo rotary shaft that connects a compressor and a turbine, and hydraulic oil is pressure-fed to a turbine chamber in which the hydraulic turbine is housed and injected into the hydraulic turbine. An auxiliary drive pump for auxiliary driving the turbo rotary shaft, and drive control means for switching the auxiliary drive pump between a state in which the turbo rotary shaft is auxiliary driven and a state in which the turbo rotary shaft is not auxiliary driven according to the operating state of the engine. In a supercharging device for an engine, a suction pump that sucks hydraulic oil in the turbine chamber to the outside of the turbine chamber, and a suction pump that operates the suction pump immediately after the auxiliary drive pump is switched from an auxiliary drive state to a non-auxiliary drive state. A supercharging device for an engine, comprising: a control means. 2. The supercharging device for an engine according to claim 1, wherein a circulation passage for circulating the working oil between the turbine chamber and the auxiliary drive pump is formed. . 3. The supercharger for an engine according to claim 1, wherein a single oil pump is also used as the auxiliary drive pump and the suction pump. 4. The engine turbocharger according to claim 3, wherein the vane-shaped rotor is housed in a swingable cam ring as the oil pump, and the eccentric direction and the eccentric amount of the cam ring with respect to the rotor are changed. The drive control means and the suction control means are configured to change the eccentricity state of the cam ring according to the operating state of the engine, by including a variable displacement vane pump that changes the discharge direction and discharge amount of the hydraulic oil. Engine supercharger. 5. The engine supercharger according to claim 3, wherein the oil pump has a discharge direction that changes depending on whether the rotational operation direction is normal or reverse. An engine supercharging device, characterized in that the drive control means and the suction control means are configured to rotate in reverse. 6. The supercharger for an engine according to claim 3, wherein a circulation passage for circulating the working oil between the turbine chamber and the oil pump is formed, and the circulation passage is formed. At the position between the suction port of the oil pump and the turbine chamber at the time of auxiliary driving, a check valve that allows the flow of hydraulic oil only in the direction from the turbine chamber to the oil pump suction port is provided. A supercharging device for an engine, characterized in that a recovery passage for collecting hydraulic oil sucked from the turbine chamber is connected to a position between the oil pump suction port and the oil pump suction port. 7. The supercharger for an engine according to claim 6, further comprising a replenishment pump for replenishing the working oil in the circulation passage, and the primary side pressure in the working oil collecting direction in the middle of the working oil collecting passage. A supercharging device for an engine, which is provided with a pressure regulator that allows the flow of hydraulic oil only when a certain value is above a certain level. 8. A turbocharger for an engine according to claim 3, wherein a hydraulic oil supply section for the turbine chamber is formed upward below the turbine chamber. Feeder. 9. The supercharger for an engine according to claim 3, wherein the oil pump is connected to the engine output shaft so as to be constantly interlocked with the oil pump, and the oil pump supplies hydraulic oil from the turbine chamber. A supercharging device for an engine, wherein the drive control means and the suction control means are configured such that the discharge capacity of the oil pump is increased as the engine speed is higher in an operation region in which the operation is performed in the suction direction.