Air compressor, internal combustion engine assembly and vehicle

Abstract

To provide an air compressor capable of suppressing an increase in noise even in multiple cylinders.SOLUTION: An air compressor includes: a cylinder block having a crank case and cylinder parts of a plurality of cylinders; a cylinder head that covers the cylinder block; a crank shaft supported within the crank case; and pistons each reciprocating within the cylinder part by the crank shaft, sucking air and compressing and discharging the sucked air. An outer wall of the cylinder block includes a first rib extending in a direction along a reciprocating direction of the piston, projecting in a direction orthogonal to the reciprocating direction of the piston and suppressing the vibration of the cylinder block.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to an air compressor, an internal combustion engine assembly, and a vehicle. [Background technology]

[0002] An air compressor is driven in conjunction with an internal combustion engine to store compressed air in an air tank for use in, for example, air brakes on a vehicle. As disclosed in Patent Document 1, for example, conventional air compressors have a single cylinder. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2008-274840 A Summary of the Invention [Problem to be solved by the invention]

[0004] To increase the amount of compressed air discharged from an air compressor, it is possible to convert a single-cylinder air compressor into a multi-cylinder one. However, simply converting a single-cylinder air compressor into a multi-cylinder one raises concerns that noises such as gear rattle and piston slap from the air compressor may increase.

[0005] An object of the present invention is to provide an air compressor, an internal combustion engine assembly, and a vehicle that can suppress an increase in noise even when multiple cylinders are used. [Means for solving the problem]

[0006] According to one aspect of the present invention, an air compressor includes a crankcase, a cylinder block having a cylinder section with multiple cylinders, a cylinder head covering the cylinder block, a crankshaft supported in the crankcase, and pistons that reciprocate within the cylinder section by the crankshaft to take in air and compress and discharge the air. An outer wall of the cylinder block is provided with a first rib that extends in a direction along the reciprocating direction of the pistons and protrudes in a direction perpendicular to the reciprocating direction of the pistons to suppress vibration of the cylinder block. [Effects of the Invention]

[0007] According to the present invention, it is possible to provide an air compressor, an internal combustion engine assembly, and a vehicle that can suppress an increase in noise even when multiple cylinders are used. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a schematic diagram illustrating a vehicle including an internal combustion engine assembly having an air compressor according to an embodiment and an internal combustion engine that serves as a power source for driving the air compressor. [Figure 2] FIG. 1 is a schematic diagram showing the relative positions of an internal combustion engine and an air compressor, as well as the arrangement of the power gear (crankshaft sprocket) of the internal combustion engine, the driven gear fixed to the crankshaft of the air compressor, and the idle gear between the power gear and the driven gear. [Figure 3] FIG. 1 is a schematic diagram showing an air compressor according to an embodiment. [Figure 4] FIG. 2 is a schematic diagram showing a crankshaft disposed in a crankcase of the air compressor according to the embodiment; [Figure 5] 1 is a schematic diagram showing a cylinder block of an air compressor according to an embodiment; [Figure 6] 3A and 3B are schematic diagrams showing ribs provided on a cylinder block of the air compressor according to the embodiment and a comparative example of the ribs; [Figure 7]1 is a schematic diagram showing a state in which an air compressor according to an embodiment is attached to an internal combustion engine; [Figure 8] A graph showing the analysis results when an air compressor is subjected to vibration in the vertical direction (horizontal axis: frequency (Hz), vertical axis: acceleration (m / s2)). [Figure 9A] A diagram showing an example of the movement of an air compressor when the input frequency in the vertical direction to the air compressor is 575 Hz (left) and 585 Hz (right). [Figure 9B] A diagram showing an example of the movement of an air compressor with an input frequency of 2178 Hz in the vertical direction (left) and 2048 Hz (right). [Figure 9C] A diagram showing an example of the movement of an air compressor with an input frequency of 2704 Hz in the vertical direction (left) and 2557 Hz (right). [Figure 10] This graph shows the analysis results when vibration is applied to an air compressor in the left-right direction (horizontal axis: frequency (Hz), vertical axis: acceleration (m / s2)). [Figure 11A] This is a diagram showing an example of the movement of an air compressor when the input frequencies to the air compressor in the left and right directions are 406 Hz (left) and 394 Hz (right). [Figure 11B] This is a diagram showing an example of the movement of an air compressor when the input frequencies to the air compressor in the left and right directions are 1906 Hz (left) and 1784 Hz (right). [Figure 11C] This is a diagram showing an example of the movement of an air compressor when the input frequencies to the air compressor in the left and right directions are 2178 Hz (left) and 2048 Hz (right). DETAILED DESCRIPTION OF THE INVENTION

[0009] The air compressor 22 of the internal combustion engine assembly 12 of the vehicle 10 according to this embodiment will be described below with reference to the drawings. Note that the relative sizes of the components in each drawing are approximate and may differ from the actual sizes.

[0010] 1, a vehicle 10 includes an internal combustion engine assembly 12 having an air compressor 22 and an internal combustion engine 24 that serves as a power source for driving the air compressor 22. An example of the vehicle 10 is a truck or a tractor.

[0011] The internal combustion engine 24 is, for example, a diesel engine.

[0012] As shown in FIG. 2, a driven gear 36 to which a crankshaft 46 of the air compressor 22 is fixed is arranged via an idle gear 34 on a power gear 32 such as a crankshaft sprocket of the internal combustion engine 24 .

[0013] The idler gear 34 is used as an intermediate gear between the power gear 32 and the driven gear 36 .

[0014] The driven gear 36 is disposed between the idle gear 34 and the power gear 32, and receives the rotational force of the power gear 32 via the idle gear 34 to be rotated.

[0015] Although the air compressor 22 shown in FIG. 3 is described as having two cylinders in this embodiment, it may have more cylinders, such as three or more cylinders.

[0016] The air compressor 22 includes a crankcase 52, a cylinder block 42 having a cylinder section 54 with multiple cylinders, a cylinder head 44 covering the cylinder section 54 of the cylinder block 42, a crankshaft 46 supported within the crankcase 52, and pistons 48a, 48b that reciprocate within the cylinder section 54 by the crankshaft 46 to draw in air from outside the air compressor 22, compress the drawn-in air, and discharge (exhaust) it outside the air compressor 22.

[0017] The cylinder block 42 and the cylinder head 44 are each made of, for example, cast iron.

[0018] An air intake port 44a and an air discharge port 44b are provided in the cylinder head 44. The air intake port 44a is formed as an opening for intake of air into the air compressor 22. An air tank (not shown) is connected to the air discharge port 44b, and compressed air compressed by pistons 48a, 48b in the air compressor 22 is discharged from the air discharge port 44b and stored in the air tank.

[0019] In this embodiment, the crankshaft 46 used is the one shown in FIG.

[0020] The crankshaft 46 includes a main shaft 46a, a main journal 46b, a first crank pin 46c, a first counterweight 46d, a connecting portion 46e, a second crank pin 46f, and a second counterweight 46g.

[0021] The first crank pin 46c is disposed between the first counterweights 46d. The central axis of the first crank pin 46c is offset from the central axes of the main shaft 46a and the main journal 46b. The first crank pin 46c is connected to one end of a first connecting rod 47a (see FIG. 3).

[0022] The second crank pin 46f is disposed between the second counterweights 46g. The central axis of the second crank pin 46f is offset from the central axes of the main shaft 46a and the main journal 46b. The second crank pin 46f is connected to one end of the second connecting rod 47b (see FIG. 3).

[0023] The central axis of the first crank pin 46c and the central axis of the second crank pin 46f are offset by, for example, 180° from the central axes of the main shaft 46a and the main journal 46b.

[0024] In this embodiment, the central axis of the connecting portion 46e coincides with the central axes of the main shaft 46a and the main journal 46b.

[0025] FIG. 5 shows the cylinder block 42.

[0026] The crankcase 52 shown in FIG. 5 is formed in a substantially cylindrical shape so that the crankshaft 46 rotates within the crankcase 52 around the central axis of the main shaft 46a and the main journal 46b.

[0027] The cylinder portion 54 is provided so as to protrude radially from the crankcase 52. The cylinder portion 54 has a first cylindrical portion 62 and a second cylindrical portion 64 arranged along the axial direction of the crankshaft 46.

[0028] 3, a first piston 48a is disposed in the first cylindrical portion 62, and a first connecting rod 47a is disposed between the crankshaft 46 and the first piston 48a. A second piston 48b is disposed in the second cylindrical portion 64, and a second connecting rod 47b is disposed between the crankshaft 46 and the second piston 48b. Preferably, the first piston 48a and the second piston 48b are formed, for example, in the shape of a cylinder with a bottom, with the bottom side disposed on the cylinder head 44 side.

[0029] As shown in Fig. 5, the outer wall of the cylinder block 42 is provided with 1-1 ribs (first ribs) 72 that extend in the direction along which the first piston 48a and the second piston 48b (see Fig. 3) reciprocate and protrude in a direction perpendicular to the direction along which the pistons 48a, 48b reciprocate, suppressing vibration of the cylinder block 42. The 1-1 ribs 72 are preferably provided on the outer peripheral surfaces of the first cylindrical portion 62 and the second cylindrical portion 64. The 1-1 ribs 72 preferably extend straight.

[0030] A 1-2 rib (third rib) 74 that is continuous with the 1-1 rib 72 is provided on the outer wall of the crankcase 52. The 1-2 rib 74 is provided so as to protrude radially outward from the outer peripheral surface of the cylindrical crankcase 52.

[0031] In addition, near the boundary between the first tubular portion 62 and the second tubular portion 64, a 1-3 rib (first rib) 76 parallel to the 1-1 rib 72 is provided.

[0032] A first-fourth rib (third rib) 78 that is continuous with the first-third rib 76 is provided on the outer wall of the crankcase 52.

[0033] A second rib 82 is provided on the outer wall of the crankcase 52, protruding radially from the central axis of the crankshaft 46 and suppressing vibration of the crankcase 52.

[0034] An inclined rib (fourth rib) 84 that intersects with the second rib 82 and the first-second rib 74 is provided on the outer wall of the crankcase 52.

[0035] Although not shown, it is preferable that the ribs 72, 74, 76, 78, 82, and 84 are similarly provided on the surface of the cylinder block 42 opposite to the side shown in FIGS.

[0036] The right diagram of Fig. 6 shows a cross-sectional view of the rib 72. The left diagram and the center diagram of Fig. 6 show comparative examples of the rib 72. The rib in the left diagram of Fig. 6 is labeled with reference numeral 721, and the rib in the center diagram of Fig. 6 is labeled with reference numeral 722.

[0037] The lower sides of the ribs 72, 721, and 721 in FIG. 6 are integrally molded with the cylinder block 42. The section modulus of the ribs 72, 721, and 721 in FIG. 6 is greater for the middle rib 722 than for the rib 721 on the left side of FIG. 6, and the right rib 72 according to this embodiment is greater than the middle rib 722. Therefore, the right side of the ribs 72, 721, and 722 shown in FIG. 6 has higher rigidity. Therefore, in this embodiment, it is preferable to use the cross section shown on the right side of FIG. 6, in which the height H of each rib 72, 74, 76, 78, 82, and 84 is greater than the width W of each rib 72, 74, 76, 78, 82, and 84. It is preferable that the ratio H / W of the height H to the width W of each rib 72, 74, 76, 78, 82, and 84 is greater than 1.

[0038] 7, the internal combustion engine assembly 12 has a block-shaped bracket 90 made of cast iron that secures the outer circumferential surface of the crankcase 52 of the air compressor 22 to, for example, the internal combustion engine 24. The bracket 90 is preferably secured to a lower fixing portion 52a of the outer circumferential surface of the crankcase 52 of the air compressor 22. By securing the air compressor 22 on or near an imaginary plane formed by the central axes of the pistons 48a, 48b, the cylinder block 42, including the crankcase 52, can suppress the generation of a moment of inertia.

[0039] The following shows the results of vibration analysis when vibrations are applied to the air compressor 22 at an appropriate frequency in the direction along which the pistons 48a, 48b move (vertical direction), and in the left-right direction perpendicular to the vertical direction of the pistons 48a, 48b. The left-right direction here refers to the direction perpendicular to an imaginary plane spanned by the two central axes defined by the two pistons 48a, 48b.

[0040] Specifically, the driving force from the power gear 32 of the internal combustion engine 24 rotates the crankshaft 46 via the idle gear 34 and the driven gear 36. As the crankshaft 46 rotates, the first piston 48a moves up and down within the first cylindrical portion 62 via the first connecting rod 47a, and the second piston 48b moves up and down within the second cylindrical portion 64 via the second connecting rod 47b. In this state, the air compressor 22 tends to vibrate both vertically and horizontally.

[0041] FIG. 8 shows the analysis results when vibration is applied to the air compressor 22 in the vertical direction. The horizontal axis represents frequency (Hz) and the vertical axis represents acceleration (m / s 2 At this time, peaks appeared when the input frequency to the air compressor 22 was around 500 Hz to 600 Hz, around 2000 Hz to 2300 Hz, and around 2500 Hz to 2800 Hz.

[0042] 9A to 9C show the results of a vibration response analysis (peak movement) of the air compressor 22 in the vertical direction. The colors in each of the figures in 9A to 9C indicate the relative displacement in each figure. That is, there is no correlation between the colors in the figure in FIG. 9A and the figure in FIG. 9B, for example.

[0043] 9A shows an example of the movement of the air compressor 22 when the input frequency to the air compressor 22 is 500 Hz or higher. As an example, the left shows an example at 575 Hz, and the right shows an example at 585 Hz. Although deformation can be seen in places, the maximum displacement is kept low, within 0.5 mm.

[0044] 9B shows an example of the movement of the air compressor 22 when the input frequency to the air compressor 22 is 2000 Hz or higher. As an example, the left shows an example at 2178 Hz, and the right shows an example at 2048 Hz. Although deformation can be seen in places, the maximum displacement is kept low, within 0.9 mm.

[0045] 9C shows an example of the movement of the air compressor 22 when the input frequency to the air compressor 22 is 2500 Hz or higher. As an example, the left shows an example at 2704 Hz, and the right shows an example at 2557 Hz. Although deformation can be seen in places, the maximum displacement is kept low, within 2 mm.

[0046] FIG. 10 shows the analysis results when vibration is applied to the air compressor 22 in the left-right direction. The horizontal axis represents frequency (Hz) and the vertical axis represents acceleration (m / s 2 At this time, peaks appeared when the input frequency to the air compressor 22 was in the range of 350 Hz to 450 Hz (up to 500 Hz), 1800 to 2000 Hz (up to 2000 Hz), and 2000 Hz to 2250 Hz (2000 Hz or higher).

[0047] 11A to 11C respectively show the analysis results of vibration response analysis (movement at each peak) of the air compressor 22 in the left-right direction.

[0048] 11A shows an example of the movement of the air compressor 22 when the input frequency to the air compressor 22 is about 500 Hz. As an example, the left shows an example at 406 Hz, and the right shows an example at 394 Hz. Although deformation can be seen in places, the maximum displacement is kept low at about 0.5 mm.

[0049] Figure 11B shows an example of the movement of the air compressor 22 when the input frequency to the air compressor 22 is 2000 Hz. As an example, the left shows an example at 1906 Hz, and the right shows an example at 1784 Hz. Although deformation can be seen in places, the maximum displacement is kept low at around 0.8 mm.

[0050] 11C shows an example of the movement of the air compressor 22 when the input frequency to the air compressor 22 is 2000 Hz or higher. As an example, the left shows an example at 2178 Hz, and the right shows an example at 2048 Hz. Although deformation can be seen in places, the maximum displacement is kept low at around 0.9 mm.

[0051] Therefore, in both of the vibration analysis results of the air compressor 22 shown in FIGS. 8 and 10, the maximum displacement was suppressed to a low level.

[0052] From the analysis and the results of testing the actual air compressor 22, it is assumed that when the pistons 48a, 48b move up and down, the case of the air compressor 22 (cylinder block 42 and cylinder head 44) ​​moves toward the front and back of Fig. 3, and therefore the presence of the 1-1 rib 72, 1-2 rib 74, 1-3 rib 76, and 1-4 rib 78 shown in Fig. 5 will have a significant effect on vibration suppression. Of these, it is assumed that the presence of the first ribs (1-1 rib 72, 1-3 rib 76) provided on the outside of the first tubular portion 62 and the second tubular portion 64 that receive the up and down movement of the pistons 48a, 48b will have a significant effect on vibration suppression.

[0053] When the crankshaft 46 of the air compressor 22 swings, the case of the air compressor 22 (cylinder block 42 and cylinder head 44) ​​moves to the front and back of Figure 3 and up and down, so it is expected that the presence of the 1-1 rib 72, the 1-2 rib 74, the 1-3 rib 76, the 1-4 rib 78, and the second rib 82 shown in Figure 5 will have a significant effect on suppressing vibration.

[0054] Furthermore, when the crankshaft 46 of the air compressor 22 swings and the pistons 48a, 48b move up and down, it is expected that not only the presence of the 1-1 rib 72, the 1-2 rib 74, the 1-3 rib 76, the 1-4 rib 78, and the presence of the second rib 82 shown in FIG. 5, but also the inclined rib 84 will suppress twisting of the crankcase 52 and have a significant effect on vibration suppression.

[0055] In this embodiment, an example in which the air compressor 22 has two cylinders has been described, but even in the case of three or more cylinders, it is possible to suppress an increase in vibration, i.e., noise, by appropriately forming ribs of similar or higher rigidity on the outer peripheral surface of the cylinder block 42.

[0056] According to this embodiment, it is possible to provide an air compressor 22 that can suppress increased vibration, i.e., noise, even when multiple cylinders are used, an internal combustion engine assembly 12 that includes the air compressor 22, and a vehicle 10 that includes the internal combustion engine assembly 12.

[0057] The present invention is not limited to the above-described embodiments, and various modifications can be made in the implementation stage without departing from the spirit of the invention. Furthermore, the embodiments may be implemented in appropriate combinations, in which case the combined effects can be obtained. Furthermore, the above-described embodiments include various inventions, and various inventions can be extracted by combining selected elements from the disclosed elements. For example, if the problem can be solved and the desired effect can be obtained even if some elements are deleted from all elements shown in the embodiments, the configuration from which these elements are deleted can be extracted as an invention. [Explanation of symbols]

[0058] 10...vehicle, 12...internal combustion engine assembly, 22...air compressor, 24...internal combustion engine, 32...power gear (crankshaft sprocket), 34...idle gear, 36...driven gear, 42...cylinder block, 44...cylinder head, 44a...air intake port, 44b...air discharge port, 46...crankshaft, 47a...first connecting rod, 47b...second connecting rod, 48a... First piston, 48b...second piston, 52...crankcase, 54...cylinder portion, 62...first cylindrical portion, 64...second cylindrical portion, 72...1-1st rib (first rib), 74...1-2nd rib (third rib), 76...1-3rd rib (first rib), 78...1-4th rib (third rib), 82...second rib, 84...inclined rib (fourth rib), 90...bracket.

Claims

1. a cylinder block having a crankcase and a cylinder portion with a plurality of cylinders; a cylinder head covering the cylinder block; a crankshaft supported within the crankcase; pistons that reciprocate within the cylinder sections by the crankshaft, take in air, and compress and discharge the air; Equipped with a first rib extending in a direction parallel to the reciprocating direction of the piston and protruding in a direction perpendicular to the reciprocating direction of the piston, the first rib suppressing vibration of the cylinder block, Air compressor.

2. The height of the first rib is greater than the width of the first rib.

2. The air compressor of claim 1.

3. a second rib that protrudes radially from the central axis of the crankshaft and suppresses vibration of the crankcase is provided on an outer wall of the crankcase; 3. The air compressor according to claim 1 or 2.

4. The height of the second rib is greater than the width of the second rib.

4. The air compressor of claim 3.

5. a third rib continuous with the first rib is provided on the outer wall of the crankcase; 3. The air compressor according to claim 1 or 2.

6. The height of the third rib is greater than the width of the third rib.

6. The air compressor according to claim 5.

7. The outer wall of the crankcase has a second rib that protrudes radially from the central axis of the crankshaft and suppresses vibration of the crankcase; a third rib continuous with the first rib; a fourth rib intersecting the second rib and the third rib; will be established, 3. The air compressor according to claim 1 or 2.

8. The air compressor according to claim 1 or 2; an internal combustion engine; a block-shaped bracket that fixes the outer peripheral surface of the crankcase of the air compressor to the internal combustion engine; An internal combustion engine assembly comprising:

9. A vehicle including the internal combustion engine assembly of claim 8.

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