JP5049673B2 - Reciprocating compressor - Google Patents

Description

  The present invention relates to a reciprocating compressor that compresses gas.

As a compressor for compressing gas, a piston having a crankcase and a cylinder attached to the crankcase and removably inserted in the cylinder is reciprocated by a crankshaft provided in the crankcase. There is a reciprocating compressor. In this type of reciprocating compressor, a separate balance weight is provided to balance the rotation of the crankshaft in order to suppress vibration and noise. For example, in a compressor in which a rotor of a motor is provided coaxially with a crankshaft, there is a technique for attaching a balance weight to the rotor of the motor that balances the rotation of the crankshaft (see, for example, Patent Document 1).
JP 2001-3869 A

  However, if a separate balance weight is attached to the rotor of the motor as described above, there is a problem that the number of parts increases.

  Therefore, an object of the present invention is to provide a reciprocating compressor capable of preventing an increase in the number of parts.

In order to achieve the above object, an invention according to claim 1 includes a crankcase, a cylinder attached to the crankcase, a piston fitted in the cylinder so as to be capable of reciprocating, and a crankcase. A crankshaft that supports the piston on a provided crank portion and reciprocates the piston in the cylinder during rotation; a disc-shaped connecting plate portion that is provided coaxially with the crankshaft outside the crankcase; and A rotor composed of a rotor magnet attached around the connecting plate part, and a motor provided around the rotor so as to face the rotor magnet and rotating the crankshaft. made in the reciprocating compressor, without providing the balancer to balance the radial direction during the rotation of the crank shaft, connecting the rotor The cutouts for balancing the radial direction during the rotation of the crank shaft is formed in a predetermined range in the circumferential direction, it is characterized by not formed on the remaining predetermined range.

  According to the first aspect of the present invention, by forming the notch portion in the rotor, the balance in the radial direction during rotation of the crankshaft is achieved, so that an increase in the number of parts can be prevented.

A reciprocating compressor according to a first embodiment of the present invention will be described below with reference to FIGS.
In FIG. 1, 1 is a tank-integrated reciprocating compressor, and the reciprocating compressor 1 compresses air as a gas. The reciprocating compressor 1 is roughly constituted by storage tanks 2 and 3, a compression unit 7, a motor 8, and the like.

  Reference numerals 2 and 3 denote a pair of storage tanks that are separated from each other in the left-right direction and extend in parallel to each other, and each of the storage tanks 2 and 3 stores compressed air supplied from the compression unit 7. Here, in order to reduce the weight, the storage tanks 2 and 3 are formed as a substantially cylindrical sealed container using, for example, an aluminum material, and are connected to each other by a connecting stay (not shown). Further, the left and right storage tanks 2 and 3 are communicated with each other by a connecting pipe 6A.

  Reference numeral 7 denotes a compression portion attached to the rear side between the storage tanks 2 and 3, and the compression portion 7 includes a crankcase 7A and a cylinder 4B attached to one side of the crankcase 7A in the left-right direction. And a high pressure side compression mechanism 7C including a cylinder 4C attached to the opposite side of the crankcase 7A in the left-right direction, so-called horizontally opposed two-stage air compressor.

  A motor 8 is provided between the storage tanks 2 and 3 and is provided on the front side of the compression unit 7. The motor 8 drives the compression unit 7 by being supplied with power from the outside. The motor 8 is a brushless motor, and includes an annular stator (stator) 8A and a rotor (rotor) 8B rotatably provided inside the stator 8A. The stator 8A has a substantially annular stator core 8Aa and a plurality of stator coils 8Ab arranged at equal pitches in the circumferential direction inside the stator core 8Aa, and the rotor 8B is a substantially annular rotor core 8Ba. And a plurality of rotor magnets 8Bb arranged at equal pitches in the circumferential direction on the outer peripheral surface of the rotor core 8Ba.

  9 is a low pressure reducing valve for reducing the primary pressure compressed air stored in the storage tanks 2 and 3 to a secondary pressure. The low pressure reducing valve 9 includes a valve portion 9A attached to the storage tank 2; It is comprised by the adjustment knob part 9B attached toward the upper side with respect to this valve part 9A. The low pressure reducing valve 9 adjusts the secondary pressure of the compressed air discharged from the quick joints 12 and 13 described later by operating the adjusting knob portion 9B.

  Reference numeral 10 denotes a low pressure manometer provided in the valve portion 9A of the low pressure reducing valve 9. The pressure gauge 10 detects and displays the secondary pressure of the compressed air adjusted by the low pressure reducing valve 9. is there.

  Reference numeral 11 denotes a branch pipe-shaped piping member attached to the valve portion 9A of the low pressure reducing valve 9. The piping member 11 includes a low pressure upper rapid joint 12 as an upper joint and a low pressure joint as a lower joint. The lower rapid joint 13 is disposed so as to be spaced apart vertically and extend substantially parallel to the front-rear direction. The quick joints 12 and 13 are connected to hoses from, for example, separate low-pressure drive type nailers (not shown). That is, the quick joints 12 and 13 are manifold types.

  14 is a high pressure reducing valve for reducing the primary pressure compressed air stored in the storage tanks 2 and 3 to a secondary pressure. The high pressure reducing valve 14 is also similar to the low pressure reducing valve 9. 14A and adjustment knob 14B.

  Reference numeral 15 denotes a high-pressure manometer provided in the valve portion 14A of the high-pressure pressure reducing valve 14. The pressure gauge 15 is also similar to the low-pressure manometer 10 in terms of compressed air adjusted by the high-pressure pressure reducing valve 14. The secondary pressure is detected and displayed.

  Reference numeral 16 denotes a branch pipe-shaped piping member attached to the valve portion 14A of the high-pressure pressure reducing valve 14. The piping member 16 includes a high-pressure upper quick joint 17 as an upper joint and a high-pressure joint as a lower joint. The lower rapid joint 18 is disposed so as to be spaced apart in the vertical direction and extend substantially parallel to the front-rear direction. The quick joints 17 and 18 are connected to hoses from, for example, separate high-pressure drive type nailers (not shown). That is, the quick couplings 17 and 18 are also manifold types.

  When the compressor 1 feeds power to the stator 8A of the motor 8 and rotates the rotor 8B, the compression mechanism 7B on the low pressure side sucks and compresses the outside air and compresses the compressed air via the pipe 6B. Supply to 7C. As a result, the high pressure side compression mechanism 7C further compresses the compressed air from the low pressure side compression mechanism 7B to form high pressure compressed air, and this high pressure compressed air is connected to the storage tank 3 and further to the connecting pipe 6A via the pipe 6C. Through the storage tank 2. For example, a plurality of nailing machine hoses (not shown) are connected to the quick joints 12, 13, 17, and 18 of the compression section 7, and the operator can use these nailers to nail nails. Work to hit. The cooling fan 19 is also rotated by the rotation of the rotor 8 </ b> B of the motor 8, and cooling air is blown to the compression unit 7.

  As shown in FIG. 2, the crankcase 7 </ b> A includes a substantially bottomed cylindrical case body 21 and an end plate 22 attached to the opening side of the case body 21. Bearings 23 and 24 are coaxially provided on the bottom of the case body 21 and the end plate 22 before and after the crankcase 7A, and the crankshaft 26 is rotatably supported by the bearings 23 and 24. One end of the crankshaft 26 protrudes from the crankcase 7A, and the rotor 8B of the motor 8 is fixed to this protruding portion. A stator 8A disposed on the outer peripheral side of the rotor 8B is attached to the end plate 22 of the crankcase 7A. The other end side of the crankshaft 26 also protrudes from the crankcase 7A, and the cooling fan 19 is fixed to this protruding portion.

  The crankshaft 26 has a pair of disc-shaped crank portions 28 and 29 that are eccentric with respect to the rotation center axis of the crankshaft 26 at a portion located in the crankcase 7A. , A swinging piston 31 that is fitted in the cylinder 4B of the compression mechanism 7B on the low pressure side so as to reciprocate is supported via a bearing 32 so as to be relatively rotatable. One end side of the connecting rod 35 is supported by the other crank portion 29 via a bearing 34 so as to be relatively rotatable, and the other end side of the connecting rod 35 can reciprocate in the cylinder 4C of the compression mechanism 7C on the high pressure side. The piston 36 is inserted and connected via a pin 37.

  As a result, by rotating the rotor 8B provided coaxially with the crankshaft 26 outside the crankcase 7A by the stator 8A of the motor 8, the crankshaft 26 rotates integrally with the rotor 8B. One crank portion 28 is eccentrically rotated to reciprocate the swinging piston 31 in the cylinder 4B, and the other crank portion 29 is also eccentrically rotated to reciprocate the piston 36 in the cylinder 4C via the connecting rod 35. .

  And in the reciprocating compressor 1 of 1st Embodiment, as shown in FIG. 3, the rotor core 8Ba holding the rotor magnet 8Bb in the rotor 8B has the cylindrical part 40 holding the rotor magnet 8Bb on the outer peripheral side; A connecting plate portion 41 is provided in the inner range of the cylindrical portion 40 and is fixed to the crankshaft 26. The connecting plate portion 41 balances in the radial direction when the crankshaft 26 rotates. For this purpose, a plurality of hole-shaped notches 42 are formed. In other words, the connecting plate portion 41 has a plurality of cutout portions 42 formed at equal intervals in a predetermined range in the circumferential direction, and the remaining predetermined range is a weight portion 43 that is not cut out. The notch 42 may be a hole or a groove.

  Here, in order to balance the radial direction at the time of rotation of the crankshaft 26 by forming the notches 42 in the rotor core 8Ba unevenly in the rotation direction in this manner, the rotor core 8Ba is provided on the crankshaft 26 in the crankcase 7A. As shown in FIGS. 2 and 4, a separate balancer for balancing the radial direction when the crankshaft 26 rotates is not provided.

  According to the reciprocating compressor 1 of the first embodiment described above, the radial balance during rotation of the crankshaft 26 is formed by forming the notches 42 in the rotor core 8Ba of the rotor 8B in an uneven manner in the rotational direction. Therefore, an increase in the number of parts can be prevented.

Next, a reciprocating compressor according to a reference technique will be described mainly with respect to differences from the first embodiment with reference to FIGS.

In the reference technique , as shown in FIG. 5, a separate balancer 45 is provided on the crankshaft 26 in the crankcase 7A (see FIG. 2) to balance the radial direction when the crankshaft 26 rotates. .

  6, the rotor core 8Ba of the rotor 8B of the motor 8 is formed with a notch 47 for balancing the axial direction during rotation of the crankshaft 26 to which the balancer 45 is attached as described above. ing. That is, a plurality of cutout portions 47 are formed at equal intervals in the circumferential range of the connecting plate portion 41, and the cutout areas of two adjacent cutout portions 47 (a) adjacent to each other are notched. It is made smaller than the part 47 (b). In other words, a weight portion 48 that is not found elsewhere is formed on the outer diameter side between the two cutout portions 47 (a) having a small area. The weight 48 serves as a counter balance for canceling the axial moment generated in the crankshaft 26 due to the axial position difference between the crank portions 28 and 29 and the balancer 45.

  That is, as schematically shown in FIG. 7, the weight of the portion related to the crank portions 28 and 29 of the crankshaft 26 is set to W1, the weight of the counter 45 is set to W2, and the point A (the support point of the crankshaft 26) If the axial distances from the bearings 24) shown in FIG. 2 are L1 and L2, the moments in the axial direction of W2, L2-W1, and L1 are generated on the crankshaft 26. The weight portion 48 that satisfies the relationship of W 2 · L 2 −W 1 · L 1 = W 3 · L 3, that is, the counter balance is provided in the rotor 8 outside the point A.

According to the reference technique described above, the notch 47 (a) and the notch 47 (b) having different shapes are formed in the rotor core 8Ba of the rotor 8B, so that the axial balance during rotation of the crankshaft 26 is achieved. Therefore, an increase in the number of parts can be prevented.

It is a perspective view which shows the compressor of 1st Embodiment of this invention. It is a plane sectional view showing the compressor of a 1st embodiment of the present invention. It is a front view which shows the motor etc. in the compressor of 1st Embodiment of this invention. It is a side view which shows the crankshaft etc. in the compressor of 1st Embodiment of this invention. It is a side view which shows the crankshaft etc. in the compressor of a reference technique . It is a front view which shows the motor etc. in the compressor of a reference technique . It is a schematic diagram which shows the relationship of the moment of the crankshaft in the compressor of a reference technique .

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Reciprocating compressor 4B, 4C Cylinder 7A Crankcase 8 Motor 8B Rotor 26 Crankshaft 28,29 Crank part 31,36 Piston 42 Notch 45 Balancer 47 Notch

Claims (1)

A crankcase,
A cylinder attached to the crankcase;
A piston inserted in the cylinder so as to be reciprocally movable;
A crankshaft that supports the piston in a crank portion provided in the crankcase and reciprocates the piston in the cylinder when rotating;
A rotor composed of a disk-shaped connecting plate portion provided coaxially with the crankshaft outside the crankcase, and a rotor magnet attached around the connecting plate portion, and facing the rotor magnet around the rotor A motor that is configured to rotate the crankshaft,
In a reciprocating compressor comprising:
A balancer for balancing the radial direction during rotation of the crankshaft is not provided, and the connecting plate of the rotor has a notch portion for balancing the radial direction during rotation of the crankshaft in the circumferential direction. A reciprocating compressor characterized in that it is formed in a predetermined range and is not formed in the remaining predetermined range .

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