JPS6332938Y2 - - 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 to eliminate the drawbacks of the prior art described above, and its purpose is to provide a rotating disk having a groove in the thickness direction on the outer periphery at one end of the crankshaft. An oil filling space with an appropriate gap formed around the groove to create a labyrinth effect, an oil storage chamber adjacent to the space and partitioned off, and a communication hole and an oil flow path for communicating these are provided, and the valve is installed. The device circulates oil only when the air compressor rotates at low speeds to apply friction torque to the rotating disk, thereby suppressing torque fluctuations during low speed rotations and reducing gear rattling noise. Another purpose is to store oil only in the oil storage chamber during medium and high speed rotation and empty the oil around the rotating disk, thereby eliminating any friction torque and reducing engine output loss. The goal is to prevent

Overview In summary, the present invention involves attaching a rotating disk having a groove in the thickness direction on the outer periphery to one end of the crankshaft of an air compressor, and creating an oil-filled space around the groove with an appropriate gap that creates a labyrinth effect. At the same time, an oil storage chamber is provided by partially partitioning the space with a partition wall having a communication hole, an oil flow path is provided that communicates the oil storage chamber with the outer periphery of the oil filling space, and The present invention is characterized in that a valve device is provided in which the communication hole is opened only during low speed rotation, and is configured to increase friction torque and reduce torque fluctuation during low speed rotation.

Configuration The present invention will be explained below based on the embodiment shown in the drawings. A gear hammer noise reduction device 1 for an air compressor according to the present invention includes a rotating disk 2 and an oil filling space 3.
The main parts include a partition wall 4, an oil storage chamber 5, an oil passage 6, and a valve device 8.

The rotating disk 2 is attached to one end 10a of the crankshaft 10 of the air compressor 9 with a nut 11, and a plurality of grooves 2b recessed in the thickness direction are formed in the outer peripheral portion 2a. The oil filling space 3 has an appropriate gap 3a formed around the groove 2b to create a labyrinth effect.
A bolt 13 is attached to the bearing portion 12a of the crankcase 12.
It is formed on the lid member 14 which is fixed with. The oil filling space 3 is partially partitioned by a partition wall 4 having a communication hole 4a, and an oil storage chamber 5 is provided adjacent to the oil storage chamber 5. An oil flow path 6 is provided between them to communicate them.

The valve device 8 consists of a plate-shaped valve body 15 and a plunger 16 that slides in the left and right directions in the figure by electromagnetic force.
a is fixed to the partition wall 4, and the other end 15b is disposed opposite to the position where it can close the communication hole 4a, and in the free state is separated from the partition wall 4 as shown by the solid line. When the electromagnetic coil 18 is energized, the plunger 16 protrudes to the left in the figure and presses the valve body 15.The electromagnetic coil 18 is connected to a power supply (not shown) via a control device (not shown) by a harness 19. (not shown). The valve device 8 is connected to the communication hole 4a of the partition wall 4.
It is designed to open only when rotating at low speeds.

A driving gear 20 is fixed to the other end 10b of the crankshaft 10, the crankshaft 10 is supported by a pair of bearings 21, and a crank pin 10c is connected to a piston pin 23 of a piston 22. A connecting rod 24 is connected thereto.

In the figure, 25 is a cylinder, 26 is a cylinder head, 27 is a suction valve, 28 is a discharge valve, and 29 is an actuator for opening the suction valve 27.

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 idling below 1000 rpm, the speed of the air compressor 9 is also low, so the electromagnetic coil 18 of the valve device 8 is not energized and the plunger 16 is retracted to the right. , the valve body 15 is in a free state and is separated from the partition wall 4,
The communication hole 4a is open. Oil filling space 3
is filled with oil, so when the crankshaft 10 rotates, the rotating disk 2 also rotates and the oil flows from the center toward the outer circumference 2a due to centrifugal force, generating a considerable amount of oil pressure within the gap 3a. However, a strong oil film is formed, and the rotating disk 2 must cut through this oil film to rotate, and the oil flows through the gap 3a.
The oil flows into the oil storage chamber 5 through the oil flow path 6, and circulates as if being sucked into the oil filling space 3 through the communication hole 4a of the partition wall 4. Therefore, the rotating disk 2 performs a considerable amount of work, and a considerable amount of friction torque acts on the rotating disk, suppressing torque fluctuations due to the dead volume generated near the top dead center of the piston 22, and reducing the crankshaft 10. rotates smoothly even at low speeds. Therefore, between the drive gear (not shown) on the engine side and the drive gear 20 on the air compressor 9 side, there is no collision between the tooth surfaces on the opposite side compared to normal, and as a result, gear hammering noise disappears. Power transmission is extremely smooth and quiet.

Next, when the air compressor 9 reaches medium to high speed rotation, for example, 1000 rpm or more, the electromagnetic coil 18 of the valve device 8 is energized, so that the plunger 1
6 protrudes and presses the valve body 15 toward the partition wall 4, so that the valve body is deformed as shown by the imaginary line, and one end 15b thereof closes the communication hole 4a. Then, due to the rotation of the rotary disk 2, the oil in the oil filling space 3 flows from the outer peripheral portion 3b through the oil flow path 6 into the oil storage chamber 5 and is stored there, and the oil circulation is stopped. Stop. Therefore, the oil in the oil filling space 3 is emptied, there is no friction torque on the rotating disk 2, and power loss is prevented. Furthermore, in this case, since the explosion noise of the engine is becoming louder, even if some gear rattling noise is generated from the drive gear 20, it does not pose a problem.

Effects Since the present invention is constructed and operates as described above, a rotating disk having a groove in the thickness direction on the outer periphery is attached to one end of the crankshaft,
The valve device is provided with an oil filling space in which an appropriate gap is formed around the groove to create a labyrinth effect, an oil storage chamber adjacent to the space and partitioned off, and a communication hole and an oil flow path that communicate these. Therefore, oil is circulated only when the air compressor rotates at low speeds to apply friction torque to the rotating disc, which has the effect of suppressing torque fluctuations during low speed rotations and reducing gear hammer noise. is obtained. In addition, during medium and high speed rotation, oil is stored only in the oil storage chamber and the oil around the rotating disk is emptied, so no friction torque is generated at all, which has the effect of preventing loss of engine output. be.

[Brief explanation of the drawing]

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 front view showing the relationship between the partition wall and the valve body. 1 is an air compressor gear knocking noise reduction device, 2
is a rotating disk, 2a is an outer circumferential portion, 2b is a groove, 3 is an oil filling space, 3a is a gap, 4 is a partition wall, 4a is a communication hole, 5 is an oil storage chamber, 6 is an oil flow path, and 8 is a valve device , 9 is an air compressor, 10 is a crankshaft, and 10a is one end.

Claims (1)

[Scope of utility model registration request] A rotating disk having a groove in the plate thickness direction is attached to one end of the crankshaft of the air compressor, and an oil-filled space is provided around the groove with an appropriate gap to create a labyrinth effect, and the space is unified. An oil storage chamber is provided by partitioning the oil storage chamber with a partition wall having a communication hole in the partition wall, and an oil flow path is provided that communicates the oil storage chamber with the outer periphery of the oil filling space, and the communication hole in the partition wall is closed only during low speed rotation. A gear knock noise reduction device for an air compressor, comprising a valve device that opens to increase friction torque during low speed rotation and reduce torque fluctuations.