JP2734598B2 - Driving force transmission device for vacuum pump - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a vacuum pump connected to a booster of a vehicle braking device, and more particularly, to a driving force transmission mechanism thereof.

[Prior Art] Conventionally, this kind of vacuum pump is driven by an engine via a belt. That is, while fixing the pulley to the crankshaft of the engine, and fixing the pulley to the driven shaft of the AC generator provided integrally with the shaft of the vacuum pump,
The configuration in which a belt is stretched between these pulleys transmits the driving force of the engine to the vacuum pump.

[Problems to be Solved by the Invention] However, in a belt driving mechanism as in the related art,
When the belt is broken while the vehicle is running, the driving force is not transmitted to the vacuum pump, and the vacuum pump enters a non-operating state. For this reason, the booster of the braking device does not work, and the braking force is reduced.

Further, the vacuum pump is provided separately from the engine crankcase, and the hydraulic pressure of the hydraulic pump on the engine side is guided through piping. For this reason, there is a problem that the function of the vacuum pump is liable to be deteriorated due to bending or blocking of the pipe.

An object of the present invention is to solve the above-mentioned problems of the conventional technology. By transmitting the driving force of an engine directly to a vacuum pump through a gear, a highly reliable and space-saving vacuum can be realized. An object of the present invention is to provide a power transmission device for a pump.

[Means for Solving the Problems] A driving force transmission device for a vacuum pump according to the present invention made to solve the above problems has a vacuum pump housed in a case integrally assembled with an engine block, A driving force transmitting device for transmitting a driving force to the vacuum pump, wherein a first driven shaft of the vacuum pump and a second driven shaft of another driving device are coaxially opposed to each other; The first and second driven shafts have first and second driven shafts.
And the first and second driven gears are always meshed with a driving gear mechanically directly connected to a crankshaft of an engine.

[Operation] In the configuration of the present invention, the vacuum pump is housed in a case integral with the engine block together with the driving gear and the like. The transmission of the driving force from the engine to the vacuum pump is performed by a driving gear mechanically directly connected to a crankshaft of the engine and a first driving gear fixed to a first driven shaft of the vacuum pump. Is performed through a mechanism that always meshes. Therefore, since power is transmitted by such gears that are always meshed, higher reliability can be obtained than with belt driving.

In addition, the driving gear on the crankshaft side of the engine is not only constantly meshed with the first driven gear of the vacuum pump, but also the second driven shaft of the second driven shaft of another driving device. Gear is always engaged. Therefore, since these devices can be integrated with the engine block, the space can be saved as compared with the case where the vacuum pump and the like are separately provided.

In addition, since each device is integrally assembled with the engine block, a lubricating oil passage can be formed along the engine block and the case, so that the external piping can be eliminated.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

1, the configuration of the present embodiment includes a gear mechanism 1 for transmitting a driving force of a diesel engine (not shown), an eccentric vacuum pump 3, and a power steering mechanism 5.

As shown in FIG. 2, the gear mechanism 1 includes a case 7 integrated with a crankcase (not shown) of the engine, a crank gear 9 provided in the case 7, and a crank gear 9 provided in the case 7. Idle gear 10 meshing with
And an injection gear 11 and a cam gear 12 that mesh with the idle gear 10, and two gears 13 and 15 that mesh with the injection gear 11.

A gear 13 shown in FIG. 1 is fixed to a driven shaft 21 of the vacuum pump 3 by a nut 17 and a key 19, and the other gear 15
Is fixed to a driven shaft 25 of a hydraulic pump of the power steering mechanism 5 by a nut 23.

The driven shaft 21 of the vacuum pump 3 is eccentrically supported by a pump case 31 via a ball bearing 33 and a metal bearing 35, and a rotor 37 is fitted and fixed to the outer periphery thereof. On the outer periphery of the rotor 37, a plurality of long grooves 39 are formed at equal intervals in the circumferential direction and radially, and each of the long grooves 39 is formed so that a part of each vane 41 can advance and retreat in the radial direction. Fitted and held. These vanes 41
Adjacent ones form a pressure chamber 43 whose volume varies with the eccentric rotation of the rotor 37. This pressure chamber 43
Is connected to a suction port 47 via a check valve 45, and a booster (not shown) of a braking device is connected to the suction port 47 via a pipeline.

Further, a lubrication path connected to a hydraulic pump driven by an engine driving force is provided in the vacuum pump 3. That is, a lubricating oil passage provided along the crankcase and the case 7 of the engine is connected to an oil supply port 51, from which an oil passage 53 in the pump case 31, an oil sump 55 on the end face side of the driven shaft 21, An oil passage 57 in the driven shaft 21 is connected to a discharge port 59 opened in the case 7 of the gear mechanism 1 through an outer circumferential gap of the driven shaft 21, and the metal bearing 35, The sliding surfaces such as the ball bearing 33 and the vane 41 are lubricated. The outlet 59
Also serves as a discharge port for air discharged from the vacuum pump 3.

 Next, the operation of the above embodiment will be described.

The rotation of the crankshaft driven by the engine drives the injection gear 11 to rotate via the crank gear 9 and the idle gear 10. This injection gear 11
Gears 13 and 15 that are always meshed by the rotational drive of
The driving force is transmitted to the motor. The gear 15 transmits driving force to the driven shaft 25 of the power steering mechanism 5. on the other hand,
The driving force of the gear 13 is transmitted to the driven shaft 21 of the vacuum pump 3 via the key 19 to rotate the rotor 37 eccentrically. Rotor 37
With the eccentric rotation of, the tip end surface of each vane 41 moves while slidingly contacting the inner surface of the pressure chamber 43, and the volume of the pressure chamber 43 gradually changes. Due to the change in volume, a pumping operation for discharging air to the discharge port 59 is performed continuously while sucking vacuum through the suction port 47. Then, a desired boosting action is performed by guiding the suction force via the suction port 47 to the brake booster of the vehicle.

Therefore, according to the above embodiment, the driving force from the engine to the vacuum pump 3 is mechanically directly connected to the gear mechanism 1 such as the injection gear 11 or the gear 13 without passing through the belt.
, The vacuum pump 3 does not stop due to the cutting of the belt, and the reliability of the booster can be improved.

Further, the vacuum pump 3 and the power steering mechanism 5
Are arranged to face each other via the gear mechanism 1 and are integrated with the crankcase, so that space can be saved.

Further, in the above embodiment, the vacuum pump 3 is integrally assembled to the crankcase via the gear mechanism 1, and the lubricating oil from the hydraulic pump to the vacuum pump 3 is supplied through an oil passage formed along the crankcase and the like. Leading.
This eliminates the need for an external piping for introducing lubricating oil as in the prior art, which not only simplifies the structure, but also has the effect of preventing a decrease in the function of the vacuum pump 3 due to blockage of the piping.

Note that the device disposed opposite to the vacuum pump is a power steering mechanism, but is not limited thereto and may be another device.

The key 19 is used to connect the driven shaft 25 of the vacuum pump 3 to the gear 13, but it is a matter of course that a screw or the like may be used.

[Effects of the Invention] As described above, according to the present invention, by transmitting the driving force of the engine directly to the vacuum pump via the gear, a highly reliable and space-saving vacuum pump can be realized. A power transmission device can be provided.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a driving force transmitting device of a vacuum pump according to an embodiment of the present invention and peripheral devices thereof, and FIG. 2 is a cross-sectional view showing a gear mechanism of the embodiment. 1 ... Gear mechanism, 3 ... Vacuum pump, 5 ... Power steering device, 7 ... Case, 9 ... Injection gear, 13 ... Gear (first driven gear), 15 ... Gear (No. 2 driven gears), 21, 25 ... driven shaft, 51 ...
Filling port, 59 …… Discharge port

Claims (1)

(57) [Claims] 1. A driving force transmitting device having a vacuum pump housed in a case integrally assembled with an engine block and transmitting a driving force to the vacuum pump, wherein a first driven shaft of the vacuum pump is provided. And a second driven shaft in another driving device are coaxially disposed opposite to each other, and first and second driven gears are fixed to the first and second driven shafts, A driving force transmitting device for a vacuum pump, wherein the first and second driven gears are always meshed with a driving gear mechanically directly connected to a crankshaft of an engine.