JPS6332939Y2 - - Google Patents

Description

[Detailed Description of the Invention] Technical Field The present invention relates to a gear knocking noise reduction device for an air compressor, and in particular, the device is installed independently of the fuel injection pump of a diesel engine, and is driven by the diesel engine via a drive gear. The present invention relates to a gear hammer noise reduction device that increases friction torque during low speed rotation of an air compressor.

Prior Art In conventional diesel engine vehicles, the air compressor was coaxially connected to the fuel injection pump, so the noise generated by the air compressor was less of a problem because the rotational fluctuations were absorbed by the fuel injection pump. It didn't happen. Recently, due to the layout of engine auxiliary equipment, air compressors are sometimes designed to be driven alone by a diesel engine via a drive gear.
In such a case, the gear hitting noise caused by the torque fluctuation of the drive gear may be heard as an abnormal noise, especially when the engine is rotating at a low speed and the explosion noise is small. This is because in a single-cylinder air compressor, torque fluctuations near the top dead center of the piston are large, and this overlaps with engine torque fluctuations when the engine is idling, resulting in loud gear hitting noise.

Purpose The present invention was made in order to eliminate the drawbacks of the prior art described above, and its purpose is to provide an oil pump with an appropriate gap formed around a rotating disk attached to one end of a crankshaft. The objective is to increase the friction torque of the crankshaft by flowing oil into the flow path only during low speed rotation, thereby suppressing torque fluctuations during low speed rotation and reducing gear rattling noise. In addition, other purposes are
The purpose is to prevent loss of engine output by preventing friction torque from occurring due to oil during high-speed rotation.

Overview In summary, the present invention attaches a rotating disk to one end of the crankshaft of an air compressor, provides an oil passage around the rotating disk with an appropriate gap, and allows oil supplied from an oil supply source to flow into the crankshaft. A bypass is provided that is returned to the case, and a flow path switching valve is provided that allows the oil supplied from the oil supply source to flow through the oil flow path during low speed rotation, and to flow the oil through the bypass during medium and high speed rotation. The air compressor is characterized in that when the air compressor rotates at low speed, friction torque is applied to the rotating disk by oil to reduce torque fluctuations.

The present invention will be explained below based on embodiments shown in the drawings. An air compressor gear knock noise reduction device 1 according to the present invention is configured with a rotating disk 2, an oil flow path 3, a bypass 4, and a flow path switching valve 5 as main parts. A rotating disk 2 is attached to one end 8a of a crankshaft 8 of the air compressor 6 by a nut 9, and an oil flow path 3 with a suitable gap 3a is provided around the rotating disk. The oil flow path is connected to a bearing portion 10a of the crankcase 10 and an oil seal 1 connected to the bearing portion by a bolt 11.
The cover member 13 is fixed to the rotary disk 2 via a cover member 13, and is provided over the entire circumference of the outer peripheral portion 2a of the rotating disk 2. Also crankshaft 8
A drive gear 14 is fixed to the other end 8b, the crankshaft 8 is supported by a pair of bearings 15, and the crank pin 8c has a connecting ring connected to the piston pin 18 of the piston 16. Rod 19 is connected.

The bypass 4 is configured so that oil supplied from an oil supply source (not shown) is returned into the crankcase 10, and one end 4a thereof is opened and connected to the oil flow path 3, and the other end is connected to the oil passage 3. 4b is opened and connected to a part of the wall surface 10b of the crankcase 10. And in the middle there is a pipe joint 20,
21 and an oil pipe 22.

The flow path switching valve 5 includes a cylindrical valve body 24 in which a T-shaped flow path 23 is formed, and a control device (not shown) that rotates the valve body in accordance with the rotation speed of the air compressor 6. It is connected to a power source (not shown) by a harness 25, and allows oil 26 supplied from an oil supply source to flow into the oil passage 3 during low speed rotation, and to flow into the bypass 4 during medium and high speed rotation. It's becoming like that. Further, a communication hole 10c communicating with the inside of the crankcase 10 is provided at the bottom of the bearing portion 10a of the crankcase 10.

When the air compressor 6 rotates at a low speed, friction torque is applied to the rotating disk 2 by the oil 26 to reduce torque fluctuations.

In the figure, 28 is a cylinder, 29 is a cylinder head, 30 is a suction valve, 31 is a discharge valve, 32 is an actuator for opening the suction valve 30, 33 is a pipe joint, 3
4 is an oil pipe.

Function The present invention is constructed as described above, and its function will be explained below. When the engine speed is low, for example when the engine is idling below 1000 rpm, the air compressor 6 also has a low rotation speed, so the flow path switching valve 5 rotates its valve body 24 as shown in FIG. 23 straight passages 23a communicate and connect the oil pipe 34 and the oil flow path 3.
As a result, oil 26 is supplied from the oil supply source.
flows into the oil flow path 3 from the oil pipe 34, hydraulic pressure is generated in the gap 3a around the outer circumference 2a of the rotating disk 2, and an oil film is formed. In this case, the rotating disk 2 of the air compressor 6 is rotating at low speed.
Since the outer circumferential portion 2a of the piston 16 must rotate through an oil film having considerable pressure and viscosity, a considerable friction torque acts on the rotary plate, and the torque due to the dead volume generated near the top dead center of the piston 16 is Fluctuations are suppressed and the crankshaft 8
rotates smoothly even at low speeds. Therefore, between the drive gear (not shown) on the engine side and the drive gear 14 on the air compressor 6 side, there is no collision between the tooth surfaces on the opposite side compared to normal times, and as a result, gear hammering noise disappears. , resulting in extremely smooth and quiet power transmission. Also, the oil 2 flowing out from the oil flow path 3
6 flows into the crankcase 10 through the communication hole 10c.

Next, when the air compressor 6 reaches medium to high speed rotation, for example, 1000 rpm or more, the flow path switching valve 5
rotates the valve body 24 90 degrees clockwise in FIG. Then, the cross flow channel 23b becomes the oil pipe 34.
At this time, the straight passages 23a communicate with one end 4a of the bypass 4, and the oil passage 3 is blocked. Therefore, the oil 26 does not flow into the oil passage 3, but flows into the crankcase 10 from the one end 4b through the bypass 4. Therefore, the friction torque due to the oil 26 does not act on the rotating disk 2 at all, and it simply idles.
Power loss is eliminated. Further, in this case, since the explosion noise of the engine is high, even if some gear rattling noise is generated from the drive gear 14, it is not a problem.

Note that the oil 26 that is supplied to the oil flow path 3 and flows into the crankcase 10 is supplied to the oil outlet 10.
d may be returned to the oil pan (not shown).

Effects Since the present invention is constructed and operates as described above, oil is allowed to flow only during low-speed rotation through the oil flow path, which has an appropriate gap around the rotating disk attached to one end of the crankshaft. Since the friction torque of the crankshaft is increased by increasing the friction torque of the crankshaft, it is possible to suppress torque fluctuations during low-speed rotation, and it is possible to achieve the effect of reducing gear rattling noise. Furthermore, during medium and high speed rotation, friction torque due to oil is prevented from occurring, which has the effect of preventing loss of engine output.

[Brief explanation of drawings]

The drawings relate to embodiments of the present invention; FIG. 1 is a vertical sectional view of an air compressor equipped with the device of the present invention;
The figure is a vertical sectional view taken along the - arrow in FIG. 1. 1 is an air compressor gear knocking noise reduction device, 2
3 is a rotating disk, 3 is an oil flow path, 3a is a gap, 4 is a bypass, 5 is a flow path switching valve, 6 is an air compressor, 8 is a crankshaft, 8a is one end, and 10 is a crankcase.

Claims (1)

[Scope of utility model registration request] A rotating disk is attached to one end of the crankshaft of the air compressor, and an oil flow path with an appropriate gap is provided around the rotating disk, and a bypass is provided so that oil supplied from an oil supply source is returned to the crankcase. A flow path switching valve is provided to flow the oil supplied from the oil supply source into the oil flow path during low speed rotation, and to flow the oil to the bypass during medium and high speed rotation, thereby reducing the low speed rotation of the air compressor. A gear hammer noise reduction device for an air compressor, characterized in that the device is configured to reduce torque fluctuations by sometimes applying oil-based friction torque to the rotating disk.