JP2023157402A - Work machine - Google Patents

Abstract

To improve performance of a work machine.SOLUTION: An air compressor has an electric motor, a piston part which reciprocates, and a case part 30 which houses the piston part. The case part 30 includes: a crank case 24 formed with a crank chamber 29; a cylinder part which defines a compression chamber with the piston part; and an intake passage 31 which allows communication between the compression chamber and the outside of the case part 30. The cylinder part is erected from an outer periphery part of the crank case 24 and has a cylindrical shape. The intake passage 31 has: an intake port 31a provided at the cylinder part and connected to the outside; a first passage 31b provided at the cylinder part and allowing communication between the intake port 31a and the crank chamber 29; and a second passage 31c provided at the cylinder part and allowing communication between the crank chamber 29 and the compression chamber.SELECTED DRAWING: Figure 9

Description

The present invention relates to a working machine such as an air compressor.

As an example of a working machine, an air compressor that can discharge compressed air to the outside is known. Such an air compressor includes a drive source, a piston that reciprocates to compress air by the driving force of the drive source, and a cylinder that accommodates the piston in a reciprocating state. Patent Document 1 describes an air compressor that causes air taken in from the engine to flow into the crank chamber, and then supplies the air to a compression chamber inside the cylinder head through an intake passage provided on the side of the cylinder.

Japanese Patent Application Publication No. 2018-150914

In the air compressor described in Patent Document 1, the air whose temperature has increased by absorbing heat from the cylinder by passing through the intake passage on the side of the cylinder is supplied to the compression chamber as it is, so the temperature of the air inside the compression chamber increases. do. Since air is compressed in this state, the temperature of the air in the compression chamber further increases, and the compression chamber is heated from the inside.

As a result, the cooling performance of the cylinder could not be improved, and the compression performance of the air compressor could not be improved. Therefore, it has been desired to improve the durability of the air compressor by improving the compression performance of the air compressor by improving the cooling performance of the cylinder, and by reducing the accompanying heat generation.

An object of the present invention is to provide a working machine with improved performance.

A work machine according to an embodiment includes a drive section having a drive shaft, a reciprocating motion converting section that converts the rotational force of the drive shaft into reciprocating power, and a piston that reciprocates in response to the reciprocating power of the reciprocating motion converting section. and a case portion that accommodates the reciprocating motion converting portion and the piston portion therein, the case portion includes a housing portion in which a housing chamber that accommodates the reciprocating motion converting portion is formed, and a housing portion that accommodates the reciprocating motion converting portion and the piston portion. a cylinder part which is erected from the outer circumferential part of the part, has a cylindrical shape in which the piston part can reciprocate, and defines a compression chamber together with the piston part; and a cylinder part which defines a compression chamber between the compression chamber and the outside of the case part. an intake passage that communicates with the intake passage; the intake passage includes an intake port that is provided in the cylinder portion and is connected to the outside; and a first intake passage that is provided in the cylinder portion and communicates between the intake port and the accommodation chamber. and a second passage provided in the cylinder portion and communicating the accommodation chamber and the compression chamber.

According to the present invention, the performance of a working machine can be improved.

1 is a perspective view showing an air compressor that is an example of a working machine according to Embodiment 1 of the present invention. 2 is a front view of the air compressor shown in FIG. 1. FIG. FIG. 3 is a cross-sectional view taken along line A-A shown in FIG. 2. FIG. FIG. 2 is a plan view showing the positional relationship between a case portion and a fan of the air compressor shown in FIG. 1. FIG. 5 is a sectional view showing the structure of the first cylinder shown in FIG. 4. FIG. FIG. 6 is a schematic diagram showing a state in which the first cylinder shown in FIG. 5 is cooled by cooling air. 5 is a sectional view showing the structure of the second cylinder shown in FIG. 4. FIG. FIG. 8 is a schematic diagram showing a cooling state of the second cylinder shown in FIG. 7 by cooling air. FIG. 2 is a conceptual diagram showing the flow of air in the case portion of the air compressor shown in FIG. 1. FIG. FIG. 2 is a perspective view showing the structure of an air passage in a case portion of the air compressor shown in FIG. 1. FIG. 11 is a perspective view showing the structure of a crank cap in the case portion shown in FIG. 10. FIG. FIG. 7 is a plan view showing the positional relationship between a case portion and a fan of an air compressor according to Embodiment 2 of the present invention. 13 is a perspective view showing the structure of an air passage in the case portion of the air compressor shown in FIG. 12. FIG. 13 is an exploded perspective view showing the installation structure of the filter section of the case section shown in FIG. 12. FIG. FIG. 7 is a plan view showing the positional relationship between a case portion and a fan of an air compressor according to Embodiment 3 of the present invention. 16 is a sectional view showing the structure of the cylinder shown in FIG. 15. FIG. FIG. 17 is a schematic diagram showing a state in which the cylinder shown in FIG. 16 is cooled by cooling air. 16 is a conceptual diagram showing the flow of air in the case portion of the air compressor shown in FIG. 15. FIG. 19 is a perspective view showing the flow of air in the case portion shown in FIG. 18. FIG. 20 is an exploded perspective view showing the structure of an air passage in the case portion shown in FIG. 19. FIG.

The work machine of this embodiment will be explained with reference to the drawings.

(Embodiment 1)
In the first embodiment, an air compressor 10 will be described as an example of a working machine. An example of an air compressor 10 is shown in FIGS. 1-4. Note that the same elements or equivalent elements shown in each figure are given the same reference numerals. The air compressor 10 includes a metal frame 11, a cover 12, an electric motor 13, a first compression section 14, a second compression section 15, a control section 16, and air tanks 17 and 18. Air tanks 17 and 18 are made of metal. Both air tanks 17 and 18 have a cylindrical shape and store compressed air. A center line A1 of the air tank 17 and a center line A2 of the air tank 18 are arranged substantially parallel to each other. A plurality of legs 19 are attached to the air tanks 17 and 18, respectively. The plurality of legs 19 contact the installation location 20 of the air compressor 10.

The frame 11 is attached from an air tank 17 to an air tank 18. The frame 11 supports an electric motor 13, a first compression section 14, and a second compression section 15. A plurality of brackets 71 are provided on each of the air tanks 17 and 18. The plurality of brackets 71 are provided at intervals in the direction along the center lines A1 and A2.

The cover 12 is made of synthetic resin, for example. The cover 12 is attached to the top of the air tanks 17 and 18 in the vertical direction, which is the direction in which gravity acts. Specifically, the cover 12 is fixed to the plurality of brackets 71 by fixing elements, for example, screw members 93.

Grips 22 and 23 are provided to be exposed to the outside. The grips 22 and 23 are provided at intervals in the direction along the center lines A1 and A2. The air compressor 10 is portable, and an operator can lift and transport the air compressor 10 by grasping the grips 22 and 23 with both hands.

The electric motor 13, the first compression section 14, and the second compression section 15 are provided inside the cover 12. That is, the electric motor 13, the first compression section 14, and the second compression section 15 are covered by the cover 12. Further, a crankcase (accommodating portion) 24 is provided inside the cover 12, and the crankcase 24 is fixed to the frame 11. As shown in FIG. 3, the crankcase 24 is provided between the first compression section 14 and the second compression section 15 in the direction along the center lines A1 and A2.

The crankcase 24 is made of metal, and a rotating shaft 25 is disposed extending from the inside to the outside of the crankcase 24. The center line B1 is an imaginary line representing the rotation center (axis line) of the rotating shaft 25. When the air compressor 10 is viewed in cross section from a plane, the center line B1 intersects the center lines A1 and A2 at a predetermined angle, for example, at an angle of approximately 90 degrees.

The electric motor 13, which is a drive unit, has a stator 26 and a rotor 27. The stator 26 is provided so as not to rotate relative to the crankcase 24. The rotor 27 is attached to a rotating shaft 25 that is a drive shaft. The electric motor 13 is, for example, a three-phase AC electric brushless motor. When electric power is supplied to the electric motor 13, the rotor 27 rotates, and thereby the rotating shaft 25 rotates.

A cooling fan 28 is attached to the rotating shaft 25. The cooling fan 28 is provided inside the cover 12. The cooling fan 28 is, for example, an axial fan. The cooling fan 28 has a plurality of blades 28a, as shown in FIG. The plurality of blades 28a are provided at intervals in the rotational direction of the cooling fan 28 with the center line B1 as the center. The cooling fan 28 is rotated by the driving force of the electric motor 13 and generates cooling air 28b (see FIG. 6, which will be described later). That is, when the cooling fan 28 is rotated, an air flow is generated.

As shown in FIG. 3, the cooling fan 28, the electric motor 13, the crankcase 24, and the control unit 16 are arranged at different positions in the direction along the center line B1.

When the air compressor 10 is placed at the installation location 20, that is, when the plurality of legs 19 are in contact with the installation location 20 as shown in FIG. 2, if the surface of the installation location 20 is approximately horizontal, the center line A1 and B1 are approximately horizontal. Further, the cooling fan 28, the electric motor 13, the crank case 24, the first compression section 14, and the second compression section 15 are located above the air tanks 17 and 18 in the direction of gravity, that is, in the vertical direction.

As shown in FIG. 3, the cover 12, the cooling fan 28, the electric motor 13, the crankcase 24, the first compression part 14, and the A second compression section 15 is arranged.

The first compression section 14 includes a first cylinder (cylinder section) 36, a first cylinder head 37, a first connecting rod 39, a first piston (piston section) 40, a first compression chamber 41, and a first exhaust chamber 42. . The first piston 40 reciprocates by the rotation of the rotating shaft 25 that is rotated by the driving force of the electric motor 13, and the cylindrical first cylinder 36 moves the first piston 40 in the direction of the central axis C1 (see FIG. 9 described later). It is housed in a state where it can be moved back and forth. The first cylinder 36 and the first cylinder head 37 are fixed to the crankcase 24. One end of the first connecting rod 39 is connected to the rotating shaft 25. The first piston 40 is provided at the other end of the first connecting rod 39. First piston 40 is operable within first cylinder 36 .

The second compression section 15 has a second cylinder (cylinder section) 45, a second cylinder head 46, a second connecting rod 48, a second piston (piston section) 49, a second compression chamber 50, and a second exhaust chamber 51. . The second piston 49 reciprocates by the rotation of the rotating shaft 25 which is rotated by the driving force of the electric motor 13, and the cylindrical second cylinder 45 allows the second piston 49 to reciprocate in the direction of the central axis C2. accommodate. The second cylinder 45 and the second cylinder head 46 are fixed to the crankcase 24. The second piston 49 is operably provided within the second cylinder 45 . One end of the second connecting rod 48 is rotatably connected to the rotating shaft 25. The other end of the second connecting rod 48 is connected to a second piston 49.

That is, in the first compression section 14, in order to convert the rotational motion of the rotating shaft 25 of the electric motor 13 into a reciprocating motion of the first piston 40, the first piston 40 is provided with one end of the first connecting rod 39. The other end of the first connecting rod 39 is rotatably connected to an eccentric cam 39b provided on the rotating shaft 25. In other words, the first connecting rod 39 spans the crankcase 24 and the first cylinder 36, and connects the rotating shaft 25 and the first piston 40.

Further, in the second compression section 15, in order to convert the rotational motion of the rotating shaft 25 of the electric motor 13 into a reciprocating motion of the second piston 49, the second piston 49 is provided with one end of the second connecting rod 48. The other end of the second connecting rod 48 is rotatably connected to an eccentric cam 48b provided on the rotating shaft 25. In other words, the second connecting rod 48 spans the crankcase 24 and the second cylinder 45 and connects the rotating shaft 25 and the second piston 49.

As described above, the rotational motion of the rotating shaft 25 of the electric motor 13 is controlled by the reciprocating motion converting section 39a consisting of the eccentric cam, the first connecting rod 39, etc., and the reciprocating motion converting section consisting of the eccentric cam, the second connecting rod 48, etc. The reciprocating motion is converted by 48a and transmitted to the first piston 40 and the second piston 49. In other words, the driving force (rotational force) of the rotating shaft 25 output from the electric motor 13 is converted into reciprocating power by the reciprocating motion converting section 39a and the reciprocating motion converting section 48a, and 2 piston 49. That is, the first piston 40 and the second piston 49 reciprocate in response to the reciprocating power of the reciprocating motion converting section 39a and the reciprocating motion converting section 48a. As a result, the first piston 40 and the second piston 49 reciprocate in directions along the central axis C1 and the central axis C2, respectively, which intersect the direction of the rotating shaft 25.

Further, one end of the connecting pipe (communication path) 60 shown in FIG. 4 is connected to the first exhaust chamber 42 shown in FIG. 3, and the other end of the connecting pipe 60 is connected to the second compression chamber 50. It is connected. The connecting pipe 60 is made of metal, for example. The connecting pipe 60 is curved and arranged so as to bypass the electric motor 13 and the cooling fan 28 .

As shown in FIG. 3, the second exhaust chamber 51 is connected to the air tanks 17 and 18. The insides of the two air tanks 17 and 18 are connected by a communication pipe (not shown), and the air pressures inside are the same.

Further, a pressure sensor 74 is provided that detects the pressure within the air tanks 17 and 18 and outputs a signal. The pressure sensor 74 projects upward from the upper end of the air tank 17. The supply pipe 76 is connected to the air tank 17 via a pressure reducing valve 75. The pressure reducing valve 75 projects upward from the upper end of the air tank 17. An operating knob 75a is attached to the pressure reducing valve 75, and the operator can operate the operating knob 75a. The pressure reducing valve 75 adjusts the pressure of the air sent from the air tank 17 to the supply pipe 76, and specifically reduces the pressure.

Further, a pressure gauge 77 that displays the air pressure within the supply pipe 76 is provided as shown in FIG. A coupler 78 is attached to supply tube 76 . The coupler 78 can be attached to and removed from the air hose. The coupler 78 is connected to other working equipment via an air hose.

Supply pipe 80 is connected to air tank 18 via pressure reducing valve 79 . An operating knob 79a is attached to the pressure reducing valve 79, and the operator can operate the operating knob 79a. The pressure reducing valve 79 adjusts the pressure of the air sent from the air tank 18 to the supply pipe 80, and specifically reduces the pressure. Further, a pressure gauge 81 that displays the air pressure within the supply pipe 80 is provided as shown in FIG. The operation knobs 75a, 79a and the pressure gauges 77, 81 are arranged to be exposed outside the cover 12. A coupler 82 is attached to supply tube 80 . The coupler 82 can be attached to and removed from the air hose. The coupler 82 is connected to other working machines via an air hose.

As shown in FIG. 1, an operating section 83 is provided on the top plate 86 of the cover 12, and the operating section 83 includes a power switch, a display panel, and the like. The control unit 16 shown in FIG. 3 is a mechanism that controls the operation and stopping of the electric motor 13. The control unit 16 is a microcomputer having an input interface, an output interface, a central processing unit, and a storage unit.

An inverter circuit is provided inside the cover 12. The control unit 16 controls the inverter circuit. A sensor for detecting the rotational phase of the electric motor 13 and a sensor for detecting the rotational speed of the electric motor 13 are provided inside the cover 12 . Signals from the pressure sensor 74, the power switch, and various sensors are input to the control unit 16. Note that the control unit 16 may include an inverter circuit.

Next, an example in which an operator uses the air compressor 10 will be described. When the operator turns on the power switch of the operating section 83, the control section 16 controls the inverter circuit, and the rotor 27 of the electric motor 13 rotates. When the rotor 27 and the rotating shaft 25 rotate together, the first piston 40 and the second piston 49 are reciprocated by the torque of the rotating shaft 25, respectively.

When the first piston 40 is actuated, air outside the cover 12 is sucked into the first compression chamber 41 of the first compression section 14, and the air is compressed in the first compression chamber 41. The air compressed in the first compression chamber 41 is discharged to the first exhaust chamber 42. When the second piston 49 is actuated, air in the first exhaust chamber 42 is sucked into the second compression chamber 50 of the second compression section 15 through the connecting pipe 60. The second compression chamber 50 further compresses the air, and the air compressed in the second compression chamber 50 is sent to the air tanks 17 and 18 via the second exhaust chamber 51. Note that the air pressure discharged from the second compression chamber 50 is higher than the air pressure discharged from the first compression chamber 41.

In this way, the air compressor 10 compresses air in two stages. The operator can perform at least one of reducing the pressure of the air in the air tanks 17 and 18 with the pressure reducing valve 75 and sending it to the supply pipe 76, or reducing the pressure with the pressure reducing valve 79 and sending it to the supply pipe 80. It is possible.

The control unit 16 processes the signal from the pressure sensor 74 to detect the air pressure in the air tanks 17 and 18. The control unit 16 controls rotation, stopping, rotation speed, and torque of the electric motor 13 based on data stored in the storage unit. When the power switch is turned on, the control unit 16 controls the rotation speed and torque of the electric motor 13 so that the air pressure in the air tanks 17 and 18 increases to the target pressure. The control unit 16 stops the electric motor 13 when the air pressure in the air tanks 17 and 18 reaches the target pressure.

Further, the cooling fan 28 rotates together with the rotating shaft 25. When the cooling fan 28 rotates, air outside the cover 12 is sucked into the interior through the plurality of air passages 34 shown in FIGS. 1 and 2. The sucked air flows within the cover 12 so as to hit the second cylinder 45 of the second compression section 15. The heat of the electric motor 13, first compression section 14, second compression section 15, crankcase 24, and control section 16 is transmitted to the air (cooling air 28b shown in FIG. 6) supplied from the cooling fan 28 and flowing inside. be done. The air that has flowed inside is discharged to the outside from a ventilation path provided on the opposite side to the ventilation path 34.

Note that, as shown in FIG. 5, the first cylinder 36 is provided with a plurality of fins 36a on its outer circumference. Further, as shown in FIG. 7, the second cylinder 45 is also provided with a plurality of fins 45a on its outer circumference. Therefore, as shown in FIGS. 6 and 8, since the air (cooling air 28b) supplied from the cooling fan 28 passes through the surfaces of the fins 36a and 45a, the first cylinder 36 and the second cylinder 45 are cooled. be done.

However, due to the arrangement of the first cylinder 36 and the second cylinder 45 and the cooling fan 28, the air (cooling air 28b) supplied from the cooling fan 28 is directed to the cooling fan 28 side of the first cylinder 36 and the second cylinder 45, respectively. Although it hits the side of the cylinder, it is difficult to hit the side of the cylinder opposite to the cooling fan 28 (the side far from the cooling fan 28). That is, in the first cylinder 36 and the second cylinder 45, it is difficult for air (cooling air 28b) to hit the side surfaces of the side far from the cooling fan 28, and the cylinders tend to become hot. In other words, the first cylinder 36 and the second cylinder 45 are not sufficiently cooled. In particular, in the case of a two-stage compression type compressor with a low pressure side and a high pressure side, such as the air compressor 10 of the first embodiment, the cylinder on the high pressure side (second cylinder 45) tends to become hotter.

Therefore, in the air compressor 10 of the first embodiment, in order to further improve the cooling efficiency of the first cylinder 36 and the second cylinder 45, the intake passage 31 is provided on the side surface of each of the first cylinder 36 and the second cylinder 45. ing.

Next, the detailed structure of the intake passage 31 and its surroundings in the air compressor 10 will be described. As shown in FIG. 9, the air compressor 10 includes a case section 30 having a reciprocating motion converting section 39a, a reciprocating motion converting section 48a, and a cylinder section. Specifically, the case part 30 includes a crank case (accommodating part) 24 in which a crank chamber (accommodating chamber) 29 that accommodates a reciprocating motion converting part 39a and a reciprocating motion converting part 48a is formed, and a first piston 40 and a first piston 40. It includes a cylinder portion that defines a compression chamber together with two pistons 49, and an intake passage 31 that communicates the compression chamber with the outside of the crankcase 24.

The cylinder section includes a first cylinder 36 on the low pressure side that is erected from the outer peripheral part of the crankcase 24 toward one side in the direction along the center axis C1 (first direction), and a first cylinder 36 on the low pressure side in the direction along the center axis C1. A second cylinder 45 on the high pressure side stands upright from the outer circumference of the crankcase 24 toward the other side of the crankcase 24 . Note that the first cylinder 36 and the second cylinder 45 have a cylindrical shape, and the first piston 40 and the second piston 49 can reciprocate inside thereof.

Further, the compression chamber includes a first compression chamber 41 on the low pressure side provided in the first cylinder 36 and a second compression chamber 50 on the high pressure side provided in the second cylinder 45. Further, the case portion 30 has a connecting pipe (communication path) 60 that supplies air exhausted from the first compression chamber 41 to the second compression chamber 50.

The intake passage 31 includes an intake port 31a provided in the second cylinder (cylinder portion) 45 and connected to the outside, and an intake port 31a provided in the second cylinder (cylinder portion) 45 and connected to the intake port 31a and the crankshaft. It has a first passage 31b that communicates with the chamber 29, and a second passage 31c that is provided in the first cylinder (cylinder part) 36 and communicates the crank chamber 29 and the first compression chamber 41. .

Further, a hose (not shown) is connected to the intake port 31a, and the tip of the hose is connected to the inside of the filter cover 12a shown in FIG. 1. The first cylinder head 37 on the low pressure side is provided on the first cylinder 36 via a pedestal 36b, and the pedestal 36b is provided with valve members 44a and 44b that allow air to flow in one direction. . Similarly, the second cylinder head 46 on the high pressure side is provided on the second cylinder 45 via a pedestal 45b, and the pedestal 45b is provided with valve members 44c and 44d that allow air to flow in one direction. There is.

Therefore, the air (E1) taken in from the outside of the air compressor 10 via the filter cover 12a and the hose passes through the first passage 31b on the side surface of the second cylinder 45 via the intake port 31a, and then passes through the first passage 31b on the side surface of the second cylinder 45. It is sent into the chamber 29 (E2). After passing through the inside of the crank chamber 29, it passes through the second passage 31c on the side surface of the first cylinder 36 (E3, E4), and then is sent to the first compression chamber 41 on the low pressure side. Further, the air compressed in the first compression chamber 41 passes through the first exhaust chamber 42 (E5), the connecting pipe 60 (E6, E7), and is sent to the second compression chamber 50. compressed to high pressure. The highly compressed air (E8) is then sent to the tank via the second exhaust chamber 51 (E9). Note that the air sent into the crank chamber 29 with an increased temperature through the first passage 31b is stirred in the crank chamber 29 and once cooled, and then passes through the second passage 31c to the first compression chamber on the low pressure side. Sent to room 41.

That is, in the air compressor 10 of the first embodiment, the air taken in from the outside is passed through the side of the cylinder on the high pressure side to cool the cylinder on the high pressure side, and the air warmed by the cooling of the cylinder on the high pressure side is transferred to the crank chamber. Send within 29 days. Further, the warmed air is stirred in the crank chamber 29 to be cooled once, and then the air whose temperature has decreased is passed through the side of the cylinder on the low pressure side to cool the cylinder on the low pressure side, and then sent to the compression chamber on the low pressure side. In other words, while cooling the high-pressure cylinder, the low-pressure cylinder is also prevented from becoming hot.

Note that either one of the first passage 31b and the second passage 31c is provided on the side surface of the cylinder portion on the opposite side to the cooling fan 28 in the direction of the center line (axis line) B1 of the rotating shaft 25 shown in FIG. It will be done. In the air compressor 10 of the first embodiment, as shown in FIGS. 10 and 11, the first passage 31b is connected to the second passage 31b on the high-pressure side opposite to the cooling fan 28 in the direction of the center line B1 of the rotating shaft 25. It is provided on the side surface of the cylinder 45. On the other hand, the second passage 31c is provided on the upper surface of the first cylinder 36 on the low pressure side. Furthermore, the first passage 31b and the second passage 31c are formed linearly along the central axis (axis) C1 and central axis C2 directions of the cylinder portion shown in FIG. That is, both the first passage 31b and the second passage 31c are formed linearly on the cylinder side surface or the cylinder top surface. Specifically, the first passage 31b is formed in the side surface of the second cylinder 45, the pedestal 45b, and the bush 24b fitted to the crankcase 24, and continues in a straight line. On the other hand, the second passage 31c is formed in the upper surface of the first cylinder 36, the pedestal 36b, and the crankcase 24, and continues in a straight line.

Further, the intake port 31a is provided at the end of the second cylinder 45 on the opposite side to the crankcase 24 in the direction of the central axis C1 of the cylinder portion. Specifically, the intake port 31a is provided in the second cylinder head 46 connected to the second cylinder 45 via the pedestal 45b in the direction of the central axis C1 of the cylinder portion, and is connected to the first passage 31b. . Thereby, the air taken in from the intake port 31a is sent to the crank chamber 29 after linearly traveling through the first passages 31b of the base 45b, the second cylinder 45, and the bush 24b.

Further, as shown in FIG. 11, the crankcase 24 has a cylindrical shape extending in a direction intersecting the direction of the central axis C1 of the cylinder portion (direction along the center line B1 along which the rotating shaft 25 shown in FIG. 3 extends). In addition, a crank cap 32 having a plurality of ribs 33 is provided on the opposite side from the cooling fan 28. The reciprocating motion converting parts 39a and 48a shown in FIG. 9 have protruding parts that protrude from the rotating shaft 25 along the radial direction L1 of the crankcase 24. For example, the protrusion is a metal balancer 24a as shown in FIG. The balancer 24a is a member for reducing unbalance caused by the reciprocating motion converters 39a and 48a, and rotates within the crankcase 24. In addition, a plurality of metal protrusions such as a first connecting rod 39 and a second connecting rod 48 are provided in the crankcase 24 to cause the first piston 40 and the second piston 49 to reciprocate. It moves back and forth. Therefore, the inside of the crank chamber 29 is stirred by the balancer 24a, the first connecting rod 39, and the second connecting rod 48 while they are being driven. At this time, since the balancer 24a, the first connecting rod 39, the second connecting rod 48, and the crankcase 24 are made of metal, they can absorb the heat of the air sent to the crank chamber 29 and lower the temperature of the air. . That is, the air that is taken in from the intake port 31a, increases in temperature by passing through the first passage 31b of the second cylinder 45, and is sent to the crank chamber 29 is heated by the balancer 24a, the first connecting rod 39, It is stirred by the protruding parts such as the second connecting rod 48, and is once cooled by taking heat from the metal balancer 24a, the first connecting rod 39, the second connecting rod 48, and the crankcase 24. The air once cooled in the crank chamber 29 is sent to the first compression chamber 41 after passing through the second passage 31c of the first cylinder 36.

Thereby, in the air compressor 10 of the first embodiment, while cooling the second cylinder 45 on the high pressure side, the first cylinder 36 on the low pressure side can also be cooled so as not to become hot. By improving the cooling performance of the first cylinder 36 and the second cylinder 45 in this way, the compression performance of the air compressor 10 can be improved. That is, the performance of the air compressor 10 can be improved. Further, since the heat generated by the compression of the air compressor 10 can be reduced, the durability of the air compressor 10 can be improved. In particular, since the second cylinder 45 on the high pressure side tends to reach a high temperature, improving the cooling performance of the second cylinder 45 on the high pressure side is more effective in improving the durability of the air compressor 10.

Further, since each of the first passage 31b and the second passage 31c is provided in a straight line, air can pass through smoothly, and the cooling effect of the first cylinder 36 and the second cylinder 45 can be further enhanced. I can do it. Further, the first passage 31b and the second passage 31c can be formed by simply forming additional linear holes in the first cylinder 36 and the second cylinder 45, so that manufacturing costs can be reduced.

In addition, a filter cover 12a is provided in a part of the cover 12, and the air intake port 31a and the filter cover 12a are connected via a hose, so that low-temperature air outside the cover 12 can be taken in after being dust-proofed. Therefore, the performance of the air compressor 10 can be further improved. Moreover, since the filter cover 12a is provided in a part of the cover 12, it becomes easier to approach the filter, and the maintainability of the air compressor 10 can be improved.

(Embodiment 2)
Embodiment 2 will be described using FIGS. 12 to 14. Embodiment 2 shows a structure in which the airflow generated by the rotation of the cooling fan 28 shown in FIG. 12 is taken in from the intake port 31a inside the cover 12 shown in FIG. 1. In the structure of the second embodiment, as shown in FIG. 14, a plurality of intake ports 31a are formed in the second cylinder head 46. The plurality of intake ports 31a are provided to communicate with the first passage 31b of the second cylinder 45. Furthermore, as shown in FIGS. 13 and 14, filter portions 43a that suppress dust from entering the intake passage 31 are attached to the plurality of intake ports 31a. Note that the filter portion 43a is covered by a filter cover 43.

By attaching the filter part 43a to the intake port 31a formed in the second cylinder head 46 in this way, vibrations caused by the rotational force of the electric motor 13 and the reciprocating motion of the piston are generated in the cylinder part. Due to the vibration, dust adhering to the filter portion 43a can be dropped and removed. Thereby, the dust removal effect of the filter part 43a can be enhanced and the performance of the air compressor 10 can be improved. Further, similarly to the air compressor 10 of the first embodiment, while cooling the second cylinder 45 on the high pressure side, the first cylinder 36 on the low pressure side can also be cooled so that it does not become hot, and as a result, the air compressor 10 compression performance can be improved.

(Embodiment 3)
Embodiment 3 shows a case where a single cylinder is used as the cylinder section. As shown in FIG. 15, only the first cylinder 36 is connected to the crankcase 24. A first cylinder head 37 is connected to the first cylinder 36 via a pedestal 36b, and the first cylinder head 37 is provided with an intake port 31a.

Also in the structure of the third embodiment, due to the arrangement of the first cylinder 36 and the cooling fan 28, as shown in FIGS. 16 and 17, the air (cooling air 28b) supplied from the cooling fan 28 is Although it hits the side of the cylinder 36 on the side of the cooling fan 28, it is difficult to hit the side of the cylinder opposite to the cooling fan 28 (the side far from the cooling fan 28). That is, air (cooling air 28b) hardly hits the side of the first cylinder 36 that is far from the cooling fan 28, and the first cylinder 36 easily becomes hot.

Therefore, in the third embodiment as well, the intake passage 31 is provided on the side surface of the first cylinder 36 in order to further increase the cooling efficiency of the first cylinder 36. Specifically, as shown in FIG. 18, the case portion 30 defines a first compression chamber 41 together with a crank case 24 in which a crank chamber 29 that accommodates a reciprocating motion converting portion 39a is formed, and a first piston 40. It includes a first cylinder 36 and an intake passage 31 that communicates the first compression chamber 41 with the outside of the crankcase 24 .

The intake passage 31 includes an intake port 31a provided in the first cylinder head 37 and connected to the outside, and an intake port 31a provided in the first cylinder 36 and communicating between the intake port 31a and the crank chamber 29. The second passage 31c is provided in the first cylinder 36 and communicates the crank chamber 29 and the first compression chamber 41.

Further, a hose (not shown) is connected to the intake port 31a, and the tip of the hose is connected to the inside of the filter cover 12a shown in FIG. 1. Further, the pedestal 36b is provided with valve members 44e and 44f that allow air to flow in one direction. As a result, as shown in FIGS. 18 to 20, air (F1) taken in from the outside passes through the first passage 31b on the side of the first cylinder 36 via the intake port 31a, and then enters the crank chamber 29. (F2). After passing through the inside of the crank chamber 29, it passes through the second passage 31c on the bottom surface of the first cylinder 36 (F3, F4), and then is sent to the first compression chamber 41. Furthermore, the air (F5) compressed in the first compression chamber 41 is sent to the outside via the first exhaust chamber 42 (F6). Here, too, the air that has increased in temperature and is sent into the crank chamber 29 through the first passage 31b is stirred in the crank chamber 29 and once cooled, and then passes through the second passage 31c to the first compression chamber 41. sent to.

That is, in the structure of the third embodiment as well, the first cylinder 36 is cooled by passing air taken in from the outside through the cylinder side surface, and the air warmed by the cooling of the first cylinder 36 is sent into the crank chamber 29. Further, the warmed air is stirred in the crank chamber 29 to be cooled once, and then the air whose temperature has decreased is passed through the bottom of the cylinder again to cool the first cylinder 36 and then sent to the first compression chamber 41.

Thereby, the cooling performance of the first cylinder 36 can be improved by cooling the first cylinder 36 more, and the compression performance of the air compressor can be improved. That is, the performance of the air compressor can be improved.

The present invention is not limited to the above-described embodiments, and can be modified in various ways without departing from the gist thereof. For example, in the structure of the third embodiment, the structure of the second embodiment may be adopted. That is, a plurality of intake ports 31a are formed in the first cylinder head 37, and the plurality of intake ports 31a are provided so as to communicate with the first passage 31b. 43a may be attached.

DESCRIPTION OF SYMBOLS 10... Air compressor (work machine), 11... Frame, 12... Cover, 12a... Filter cover, 13... Electric motor (drive part), 14... First compression part, 15... Second compression part, 16... Control part , 17, 18...Air tank, 19...Legs, 20...Installation location, 22, 23...Grip, 24...Crankcase (accommodating part), 24a...Balancer (protruding part), 24b...Bushing, 25...Rotating shaft ( drive shaft), 26... stator, 27... rotor, 28... cooling fan (fan), 28a... blade, 28b... cooling air, 29... crank chamber (housing chamber), 30... case part, 31... intake passage, 31a...Intake port, 31b...First passage, 31c...Second passage, 32...Crank cap, 33...Rib, 34...Air passage, 36...First cylinder (cylinder part), 36a...Fin, 36b...Pedestal, 37 ...first cylinder head, 39...first connecting rod (protruding part), 39a...reciprocating motion converter, 39b...eccentric cam, 40...first piston (piston part), 41...first compression chamber, 42...first Exhaust chamber, 43... Filter cover, 43a... Filter part, 44a, 44b, 44c, 44d, 44e, 44f... Valve member, 45... Second cylinder (cylinder part), 45a... Fin, 45b... Pedestal, 46... Second Cylinder head, 48... Second connecting rod (protruding part), 48a... Reciprocating motion converter, 48b... Eccentric cam, 49... Second piston (piston part), 50... Second compression chamber, 51... Second exhaust chamber, 60... Connection pipe (communication path), 71... Bracket, 74... Pressure sensor, 75... Pressure reducing valve, 75a... Operation knob, 76... Supply pipe, 77... Pressure gauge, 78... Coupler, 79... Pressure reducing valve, 79a... Operation Knob, 80... Supply pipe, 81... Pressure gauge, 83... Operating unit, 86... Top plate, 93... Screw member, A1, A2... Center line, B1... Center line (axis line), C1, C2... Center axis (axis line) ), E1 to E9...air flow, F1 to F6...air flow, L1...radial direction

Claims (10)

a drive section having a drive shaft;
a reciprocating motion converter that converts the rotational force of the drive shaft into reciprocating power;
a piston part that reciprocates in response to reciprocating power of the reciprocating motion conversion part;
a case portion that accommodates the reciprocating motion conversion portion and the piston portion therein;
has
The case part is
an accommodating section in which a accommodating chamber for accommodating the reciprocating motion conversion section is formed;
a cylinder part that stands up from an outer peripheral part of the housing part, has a cylindrical shape in which the piston part can reciprocate, and defines a compression chamber together with the piston part;
an intake passage that communicates the compression chamber with the outside of the case portion;
including;
The intake passage is
an intake port provided in the cylinder portion and connected to the outside;
a first passage provided in the cylinder portion and communicating between the intake port and the storage chamber;
a second passage provided in the cylinder portion and communicating the storage chamber and the compression chamber;
A working machine with The cylinder portion includes a first cylinder erected from an outer peripheral portion of the accommodating portion toward one side in a first direction, and a first cylinder erected from an outer periphery of the accommodating portion toward the other side in the first direction. a second cylinder;
the first passage is provided in the second cylinder,
The working machine according to claim 1, wherein the second passage is provided in the first cylinder. The compression chamber includes a first compression chamber provided in the first cylinder and a second compression chamber provided in the second cylinder,
The case portion has a communication path that supplies air exhausted from the first compression chamber to the second compression chamber,
The intake port is provided in the second cylinder,
The working machine according to claim 2, wherein the second passage communicates the storage chamber and the first compression chamber. The working machine according to claim 1, wherein the cylinder section has a single cylinder. a fan rotatable using the drive shaft as a rotation axis;
The operation according to any one of claims 1 to 4, wherein at least one of the first passage and the second passage is provided on a side surface of the cylinder portion opposite to the fan in the axial direction of the drive shaft. Machine. The working machine according to claim 5, wherein the first passage is provided on a side surface of the cylinder section opposite to the fan in the axial direction of the drive shaft. The housing portion has a cylindrical shape extending in a direction intersecting an axial direction of the cylinder portion,
The working machine according to claim 1, wherein the reciprocating motion converter has a protrusion that protrudes from the drive shaft in a radial direction of the accommodating part. The working machine according to claim 1, wherein the intake port is provided at an end of the cylinder portion opposite to the housing portion in the axial direction of the cylinder portion. 9. The work machine according to claim 8, further comprising a filter section attached to the intake port to suppress dust from entering the intake passage. The working machine according to claim 1, wherein the first passage and the second passage are formed linearly along the axial direction of the cylinder portion.

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