Drive device including oscillation linear drive mechanism

Abstract

To provide a drive device which can stably conduct power conversion from rotational movement into linear movement and achieves high operation efficiency.SOLUTION: A drive device includes: a housing 12; a first crank shaft CR1 in which both ends of main shafts M1, M2 are supported by the housing 12; a second crank shaft CR2 supported by an eccentric shaft M3 and including a first journal part JA1 and a second journal part JA2; a first slider S1 provided at the first journal part JA1; a second slider S2 provided at the second journal part JA2; a first movable body which linearly moves as the first journal part JA1 moves; a first guide body 30 which is provided at the housing 12 and guides movement of the first slider S1; a second guide body 32 which is provided at the housing 12 and guides movement of the second slider S2; and a third guide body 14a which is provided at the housing 12 and guides linear movement of the first movable body.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] An embodiment of the present invention relates to a drive device including an oscillating linear drive mechanism that converts the rotation and oscillating motion of an eccentrically rotating rotor into linear motion. [Background technology]

[0002] The double eccentric arc oscillating mechanism is known as a mechanism for converting rotary motion into linear motion. In the double eccentric arc oscillating mechanism, the eccentric shaft on one side moves linearly by setting the radius of the double circular eccentric mechanism at a specific ratio. In this type of oscillating mechanism, the crankshaft (eccentric shaft) that supports the reciprocating part as the moving body is supported by a cantilever structure. If the oscillating fulcrum is located directly below the reciprocating part, an input / output shaft can be provided at one end of the eccentric shaft. However, if the oscillating fulcrum is located directly below the reciprocating motion part, when an external force acts on the reciprocating motion part, the cantilevered eccentric shaft may deform, causing a disruption to the motion of the oscillating fulcrum part. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6593945 [Patent Document 2] Patent No. 6755542 Summary of the Invention [Problem to be solved by the invention]

[0004] An object of the embodiments of the present invention is to provide a drive device that can stably convert rotational motion into linear motion and has high operating efficiency. [Means for solving the problem]

[0005] According to an embodiment, a drive device includes a housing, a main shaft having a first central axis, and an eccentric shaft having a second central axis parallel to the first central axis and positioned eccentrically with respect to the main shaft, a first crankshaft in which both axial ends of the main shaft are supported by the housing so as to be rotatable about the first central axis, a second crankshaft supported by the eccentric shaft so as to be rotatable about the second central axis, and including a first journal portion eccentric in one direction with respect to the second central axis and a second journal portion eccentric in another direction with respect to the second central axis, and a first journal portion eccentrically provided on the first journal portion so as to be rotatable. the housing includes a slider, a second slider rotatably mounted on the second journal portion, a first moving body rotatably connected to the first journal portion and performing linear motion in a first direction perpendicular to the first central axis in response to movement of the first journal portion, a first guide body provided on the housing for guiding the movement of the first slider along the first direction, a second guide body provided on the housing for guiding the linear movement of the second slider in a second direction perpendicular to the first central axis and perpendicular to the first direction, and a third guide body provided on the housing for guiding the linear movement of the first moving body in the first direction. Effect of the Invention

[0006] According to the present invention, it is possible to provide a drive device that can stably convert rotational motion into linear motion and has high operating efficiency. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a perspective view showing the appearance of a drive device according to a first embodiment. [Diagram 2] FIG. 2 is a perspective view of a drive mechanism of the drive device. [Diagram 3] FIG. 3 is an exploded perspective view of the drive mechanism. [Figure 4] FIG. 4 is a side view of the drive mechanism. [Diagram 5] FIG. 5 is a cross-sectional view of the drive device. [Figure 6]FIG. 6 is a side view of the drive device, with a part of the housing cut away. [Figure 7] FIG. 7 is another side view of the drive device with a part of the housing cut away. [Figure 8] FIG. 8 is a side view of a drive mechanism of a drive device according to a first modified example. [Figure 9] FIG. 9 is a side view of a drive mechanism of a drive device according to a second modified example. [Figure 10] FIG. 10 is a side view of a drive mechanism of a drive device according to a third modified example. [Figure 11] FIG. 11 is a side view of a drive mechanism of a drive device according to a fourth modified example. [Figure 12] FIG. 12 is a perspective view showing a drive mechanism of a drive device according to a second embodiment. [Figure 13] FIG. 13 is a perspective view showing a drive mechanism of a drive device according to a third embodiment. [Figure 14] FIG. 14 is a perspective view showing a drive mechanism of a drive device according to a fourth embodiment. [Figure 15] FIG. 15 is a perspective view showing a drive mechanism of a drive device according to a fifth embodiment. [Figure 16] FIG. 16 is a perspective view showing a drive mechanism of a drive device according to a sixth embodiment. [Figure 17] FIG. 17 is a perspective view showing a drive mechanism of a drive device according to a sixth embodiment. [Figure 18] FIG. 18 is a side view of the drive device in the sixth embodiment, with a part of the housing 12 cut away. [Figure 19] FIG. 19 is another side view of the drive device in the sixth embodiment, with the housing 12 partially cut away. [Figure 20] FIG. 20 is a perspective view of a drive mechanism including a first modified example of a guide plate for a slider. [Figure 21] FIG. 21 is a side view showing a first modified example of a guide plate. [Figure 22] FIG. 22 is a side view showing a second modified example of the guide plate. [Figure 23] FIG. 23 is a side view of a drive mechanism including a third modified example of a guide plate. [Figure 24]FIG. 24(a) is a perspective view showing a first modified example of the slider, and FIG. 24(b) is a perspective view showing a second modified example of the slider. [Diagram 25] FIG. 25 is a perspective view showing a modified example of the second crankshaft. [Figure 26] FIG. 26 is a perspective view of a journal portion in a modified example of the second crankshaft. [Figure 27] FIG. 27 is a side view showing a first modified example of the inner counterweight. [Figure 28] FIG. 28 is a perspective view of a first modified internal counterweight attached to a journal portion. [Figure 29] FIG. 29 is a side view showing a second modified example of the inner counterweight. [Diagram 30] FIG. 30 is a perspective view of a second modified inner counterweight attached to a journal portion. [Diagram 31] FIG. 31 is a front view, seen from a radial direction, of a state in which an eccentric shaft is inserted into a modified second crankshaft. [Diagram 32] FIG. 32 is a cross-sectional view taken along the axial direction of a journal portion in a modified example of the second crankshaft. [Diagram 33] FIG. 33 is a front view of the eccentric shaft as viewed from the radial direction. [Diagram 34] FIG. 34 is a front view in which the outer shape of a modified second crankshaft is superimposed on FIG. 33. [Diagram 35] FIG. 35(a) is a perspective view showing a modified example of the second counterweight, and FIG. 35(b) is a perspective view showing a modified example of the first counterweight. [Diagram 36] FIG. 36 is a cross-sectional view along the axial direction of a modified example in which the eccentric shaft and one of the counterweights are integrated. [Figure 37] FIG. 37 is a cross-sectional view along the axial direction of the crankshaft assembly. [Figure 38] FIG. 38 is an axial cross-sectional view of a modified second crankshaft with a connecting rod and a slider attached to a journal portion. [Figure 39] FIG. 39 is a side view showing how one piston of the crankshaft assembly is inserted into the cylinder sleeve. [Diagram 40] 40 is a side view showing how the other piston is inserted into the cylinder sleeve after FIG. 39. FIG. [Diagram 41] FIG. 41(a) is a perspective view showing a modified example of one cylinder sleeve, and FIG. 41(b) is a perspective view showing a modified example of the other cylinder sleeve. [Diagram 42] FIG. 42(a) is a perspective view showing a connector for a motor drive shaft in a contracted state, and FIG. 42(b) is a perspective view showing a connector for a motor drive shaft in an expanded state. [Diagram 43] FIG. 43 is an axial cross-sectional view showing a state in which a motor drive shaft is connected to a main shaft of a drive mechanism. [Diagram 44] FIG. 44(a) is a side view of one connecting rod of the drive mechanism as viewed from the axial direction, and FIG. 44(b) is a side view of the other connecting rod of the drive mechanism as viewed from the axial direction. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Note that the disclosure is merely an example, and those who are skilled in the art can easily conceive of appropriate modifications while maintaining the gist of the invention are naturally included in the scope of the present invention. In addition, in order to make the explanation clearer, the drawings may show the width, thickness, shape, etc. of each part in a schematic manner compared to the actual embodiment, but these are merely examples and do not limit the interpretation of the present invention. In addition, in this specification and each figure, elements similar to those described above with respect to the previous figures may be given the same reference numerals, and detailed explanations may be omitted as appropriate.

[0009] (First embodiment) FIG. 1 is a perspective view showing a schematic external appearance of a drive device according to a first embodiment, and FIG. 2 is a perspective view showing a drive mechanism of the drive device. In this embodiment, the drive device 10 is configured as, for example, a two-cylinder compressor or generator. As shown in Fig. 1, the drive device 10 includes a substantially rectangular box-shaped housing (crankcase) 12, a first cylinder 14a and a second cylinder 14b attached to the housing 12, and a two-axis oscillating linear drive mechanism (hereinafter referred to as the drive mechanism) 20 provided in the housing 12 and in the first and second cylinders 14a and 14b. In one example, the housing 12 has a rectangular bottom wall 12a, a first side wall 12b and a second side wall 12c each having a substantially pentagonal shape standing along two opposing sides of the bottom wall 12a, a third side wall 12d and a fourth side wall 12e standing along the other two opposing sides of the bottom wall 12a, and a first ceiling wall 13a and a second ceiling wall 13b connected to the upper edges of the first to fourth side walls. The first and second ceiling walls 13a and 13b are inclined with respect to the bottom wall 12a and face each other at an angle of approximately 90 degrees.

[0010] The first cylinder 14a functioning as a third guide body is installed on the first ceiling wall 13a and extends in a direction perpendicular to the first ceiling wall 13a (Y direction). The second cylinder 14b functioning as a fourth guide body is installed on the second ceiling wall 13b and extends in a direction perpendicular to the second ceiling wall 13b (Z direction). The Y direction and the Z direction are perpendicular to each other, and the first cylinder 14a and the second cylinder 14b are disposed at an angle of approximately 90 degrees.

[0011] A first guide body 30 and a second guide body 32 are provided inside the housing 12. The first and second guide bodies 30, 32 are fixed to the inner surface of the housing 12. As will be described later, the first guide body 30 and the second guide body 32 guide the linear motion of a slider of the drive mechanism 20.

[0012] The drive mechanism 20 includes a first crankshaft (inner crankshaft) CR1, a second crankshaft (outer crankshaft) CR2, a first slider S1 and a second slider S2 mounted on the second crankshaft CR2, and a first piston P1 and a second piston P2 connected to the second crankshaft CR2. The first crankshaft CR1 includes a pair of main shafts extending along a first central axis C1. These main shafts are rotatably supported by bearings B1 and B2 provided on the first side wall 12b and the second side wall 12c of the housing 12. As a result, the first crankshaft CR1 is supported at both ends by the housing 12 with the first central axis C1 coinciding with the X direction. The X direction is perpendicular to the Y direction and the Z direction and parallel to the bottom wall 12a of the housing 12. The first piston P1 is disposed in the first cylinder 14a and moves linearly up and down in the Y direction. The second piston P2 is disposed in the second cylinder 14b and moves linearly up and down in the Z direction. The first slider S1 attached to the second crankshaft CR2 is guided by the first guide body 30 and moves linearly in the Y direction. The second slider S1 attached to the second crankshaft CR2 is guided by the second guide body 32 and moves linearly in the Z direction.

[0013] Next, the configuration of the drive mechanism 20 will be described in detail. FIG. 2 is a perspective view of the drive mechanism, and FIG. 3 is an exploded perspective view of the drive mechanism. As shown in the figure, the drive mechanism 20 has a first crankshaft (inner crankshaft) CR1 and a second crankshaft (outer crankshaft) CR2 rotatably supported by the first crankshaft CR1. The first crankshaft CR1 has a pair of main shafts M1 and M2 having a first central axis C1 and an eccentric shaft M3 having a second central axis C2. The pair of main shafts M1 and M2 are spaced apart from each other in the axial direction by a predetermined length. One main shaft M1 is connected to one end of the eccentric shaft M3 via a first counterweight W1. The other main shaft M2 is connected to the other end of the eccentric shaft M3 via a second counterweight W2. The second central axis C2 of the eccentric shaft M3 is parallel to the first central axis C1 and is spaced apart (eccentric) from the first central axis C1 by a predetermined distance. In this embodiment, the main shaft M2, the second counterweight W2, and the eccentric shaft M3 are integrally formed, and the main shaft M1 and the first counterweight W1 are integrally formed. The other end of the eccentric shaft M3 is detachably connected to the first counterweight W1.

[0014] The main shaft M1 is rotatably supported by the housing 12 via a bearing (e.g., a ball bearing) B1. The main shaft M2 is rotatably supported by the housing 12 via a bearing (e.g., a ball bearing) B2. At least one of the main shafts, for example the main shaft M2, protrudes to the outside from the housing 12 and constitutes an input / output shaft. The other main shaft M1 may be used as the input / output shaft.

[0015] As shown in Fig. 3, the second crankshaft CR2 has a cylindrical first journal portion JA1, a cylindrical second journal portion JA2, and a disk-shaped base portion BA located between the first journal portion JA1 and the second journal portion JA2. The base portion BA has a central axis CB1. The first journal portion JA1 is formed to have a smaller diameter than the base portion BA, and is positioned eccentrically with respect to the central axis CB1 of the base portion BA. The second journal portion JA2 is formed to have a smaller diameter than the base portion BA, and is positioned eccentrically with respect to the central axis CB1 of the base portion BA in the opposite direction to the first journal portion JA1. That is, the first journal portion JA1 has a center axis CG1 that is parallel to the center axis CB1 of the base portion BA and is spaced a predetermined distance radially from the center axis CB1, and the second journal portion JA2 has a center axis CG2 that is parallel to the center axis CB1 of the base portion BA and is spaced a predetermined distance radially from the center axis CB1 by 180 degrees in the opposite direction from the center axis CB1. The second crankshaft CR2 has a through hole 22 extending through the first journal portion JA1, the base portion BA, and the second journal portion JA2. The through hole 22 extends coaxially with the central axis CB1 of the base portion BA, and opens to an end face of the first journal portion JA1 and an end face of the second journal portion JA2.

[0016] The drive mechanism 20 further includes a first piston P1, a second piston P2, a first slider S1, a second slider S2, a first internal counterweight IW1, and a second internal counterweight IW2. The first slider S1 and the first internal counterweight IW1 are attached to a first journal portion JA1 of the second crankshaft CR2, and the first piston P1 is connected to the first journal portion JA1 via a connecting rod CN1. The second slider S2 and the second internal counterweight IW2 are attached to a second journal portion JA2 of the second crankshaft CR2, and the second piston P2 is connected to the second journal portion JA2 via a connecting rod CN2. In this embodiment, the first piston P1 has a larger diameter than the second piston P2. The first piston P1 and the connecting rod CN1 constitute a first moving body, and the second piston P2 and the connecting rod CN2 constitute a second moving body.

[0017] Fig. 4 is a side view of the drive mechanism 20, and Fig. 5 is a cross-sectional view of a drive device including the drive mechanism 20. As shown in the figures, the main shafts M1, M2 of the first crankshaft CR1 are supported rotatably about a first central axis C1 on the side walls 12b, 12c of the housing 12 via bearings B1, B2. The first central axis C1 extends substantially parallel to the bottom wall 12a of the housing 12. The eccentric shaft M3 of the first crankshaft CR1 is inserted into the through hole 22 of the second crankshaft CR2. The second crankshaft CR2 is supported by the eccentric shaft M3 so as to be rotatable about the central axis C2. When the first crankshaft CR1 rotates about the first central axis C1, the second crankshaft CR2 revolves about the first central axis C1. When the second crankshaft CR2 rotates about the second central axis C2, the first journal portion JA1 revolves about the second central axis C2, and the second journal portion JA2 revolves about the second central axis C2. As a result, the first journal portion JA1 moves linearly in the Y direction, and the second journal portion JA2 moves linearly in the Z direction. In this manner, the first journal portion JA1 and the second journal portion JA2 each constitute a swing fulcrum that converts rotational motion into linear motion.

[0018] One end of the connecting rod CN1 is rotatably connected to the first piston P1 via a piston pin. The other end of the connecting rod CN1 is rotatably connected to the outer circumferential surface of the first journal portion JA1. As a result, the first piston P1 is connected to the second crankshaft CR2 via the connecting rod CN1. The first piston P1 and the connecting rod CN1 move linearly in the Y direction in conjunction with the linear motion of the first journal portion JA1. At that time, the first cylinder 14a functions as a guide body that guides the linear movement of the first piston P1 in the Y direction. The first inner counterweight IW1 is connected to the outer circumferential surface of the first journal portion JA1 and extends radially outward from the first journal portion JA1. In one example, the first slider S1 is formed in an annular shape. The first slider is attached to the outer circumferential surface of the first journal portion JA1 via a bearing and is attached so as to be freely rotatable about the central axis CG1 of the first journal portion JA1. In this embodiment, in the first journal portion JA1, the connecting rod CN1, the first inner counterweight IW1, and the first slider S1 are arranged in this order from the base portion BA.

[0019] One end of the connecting rod CN2 is rotatably connected to the second piston P2 via a piston pin. The other end of the connecting rod CN2 is rotatably connected to the outer circumferential surface of the second journal portion JA2 of the second crankshaft CR2. As a result, the second piston P2 is connected to the second crankshaft CR2 via the connecting rod CN2. The second piston P2 and the connecting rod CN2 move linearly in the Z direction in conjunction with the linear motion of the second journal portion JA2. At that time, the second cylinder 14b functions as a guide body that guides the linear movement of the second piston P2 in the Z direction. The second inner counterweight IW2 is connected to the outer circumferential surface of the second journal portion JA2 and extends from the second journal portion JA2 in the radial direction opposite to that of the first inner counterweight IW1. In one example, the second slider S2 is formed in an annular shape and is attached to the outer circumferential surface of the second journal portion JA2 via a bearing. The second slider S2 is attached so as to be rotatable about the central axis CG2 of the second journal portion JA2. In this embodiment, in the second journal portion JA2, the connecting rod CN2, the second inner counterweight IW2, and the second slider S2 are arranged in this order from the base portion BA.

[0020] FIG. 6 is one side view of the drive device with a portion of the housing 12 cut away, and FIG. 7 is another side view of the drive device with a portion of the housing 12 cut away. 5 and 6, the first guide body 30, which guides the linear motion of the first journal portion JA1 and the first slider S1 as a swing fulcrum, includes, for example, a pair of guide plates 30A, 30B. The guide plate 30A is provided substantially perpendicularly to the bottom wall 12a and the side wall 12e of the housing 12. The guide plate 30A has a guide surface 30a formed of a side edge that extends linearly in the Y direction. The guide plate 30B is provided substantially perpendicular to the second top wall 13b and the third side wall 12d of the housing 12. The guide plate 30B has a guide surface 30b formed of a side edge that extends linearly in the Y direction. The guide surface 30b faces the guide surface 30a in parallel at a distance substantially equal to the diameter of the first slider S1.

[0021] The guide plates 30A and 30B are provided at the same position as the first slider S1 in the X direction. The first slider S1 is sandwiched between the guide surfaces 30a and 30b, and the outer circumferential surface of the first slider S1 is in contact with the guide surfaces 30a and 30b. As a result, the first slider S1 is guided in the Y direction by the guide surfaces 30a and 30b when it moves linearly in the Y direction.

[0022] 5 and 7, the second guide body 32, which guides the linear motion of the second journal portion JA2 and the second slider S2 as a swing fulcrum, includes, for example, a pair of guide plates 32A, 32B. The guide plate 32A is provided substantially perpendicularly to the bottom wall 12a and the side wall 12d of the housing 12. The guide plate 32A has a guide surface 32a formed of a side edge that extends linearly in the Z direction. The guide plate 32B is provided substantially perpendicular to the first top wall 13a and the fourth side wall 12e of the housing 12. The guide plate 32B has a guide surface 32b formed of a side edge that extends linearly in the Z direction. The guide surface 32b faces the guide surface 32a in parallel at a distance substantially equal to the diameter of the second slider S2. The guide plates 32A and 32B are provided at the same position as the second slider S2 in the X direction. The second slider S2 is located between the guide surfaces 32a and 32b, and the outer circumferential surface of the second slider S2 is in contact with the guide surfaces 32a and 32b. As a result, the second slider S2 is guided in the Z direction by the guide surfaces 32a and 32b when it moves linearly in the Z direction.

[0023] The operation of the driving device 10 configured as above will be described. For example, when the drive unit 10 is used as a compressor, a rotational force is input to one of the main shafts M2, causing the first crankshaft CR1 to rotate about the first central axis C1. Accordingly, the second crankshaft CR2 revolves about the first central axis C1 and rotates about the second central axis C2. Furthermore, the first journal portion JA1 of the second crankshaft CR2 revolves about the second central axis C2, and the second journal portion JA2 revolves about the second central axis C2.

[0024] As a result, the first journal portion JA1, the first slider S1 attached to the first journal portion JA1, the first inner counterweight IW1, the connecting rod CN1, and the first piston P1 move linearly in the Y direction. The linear motion of the first journal portion JA1 and the first slider S1 is linearly guided by the first guide body 30. Furthermore, the linear motion of the first piston P1 is guided by the first cylinder 14a. As the first piston P1 moves up and down within the first cylinder 14a, the gas (air, refrigerant, etc.) within the first cylinder 14a is compressed and pressurized, and is supplied to the outside from a discharge port (not shown).

[0025] The second journal portion JA2 of the second crankshaft CR2, and the second slider S2, second inner counterweight IW2, connecting rod CN2, and second piston P2 attached to the second journal portion JA2, move linearly in the Z direction. The linear motion of the second journal portion JA2 and the second slider S2 is linearly guided by the second guide body 32. Furthermore, the linear motion of the second piston P2 is guided by the second cylinder 14b. As the second piston P2 moves up and down within the second cylinder 14b, the gas (air, refrigerant, etc.) within the second cylinder 14b is compressed and pressurized, and is supplied to the outside from a discharge port (not shown).

[0026] In the case where the first piston P1 and the second piston P2 have different diameters as in this embodiment, a so-called two-stage compression compressor can be realized. That is, the first stage compression operation is performed using the large-diameter first piston P1 to pressurize the pressure to an approximately desired pressure, and then the second stage compression operation is performed using the small-diameter second piston P2 to adjust the pressurized state.

[0027] According to the drive device 10 according to the first embodiment configured as described above, the first crankshaft CR1 of the two-shaft oscillating linear drive mechanism 20 is supported rotatably at both ends, so that the second crankshaft CR2 constituting the oscillating fulcrum can be stably supported and the occurrence of defects occurring at the oscillating fulcrum can be prevented. At the same time, both shaft ends of the first crankshaft CR1 and the main shafts M1 and M2 can be used as input and output shafts. Furthermore, the first journal portion JA1 and the second journal portion JA2 constituting the oscillating fulcrum are guided by the guide bodies 30 and 32 provided in the housing 12, so that the oscillating fulcrum can perform stable and smooth linear motion. Furthermore, even if a reciprocating body (piston) is arranged directly under the oscillating fulcrum, the smooth linear motion of the oscillating fulcrum is not impeded. From the above, a highly efficient and low-vibration drive device can be obtained.

[0028] The drive device 10 is not limited to being applied to a compressor, but may also be applied to a generator, an engine, etc. In this case, a valve mechanism, a fuel supply means, an ignition means, and an exhaust mechanism are provided in the cylinder heads of the first cylinder 14a and the second cylinder 14b, and fuel is supplied to the first and second cylinders 14a, 14b, ignited, burned, and exhausted, thereby driving the first and second pistons P1, P2 in the Y direction and the Z direction, respectively, to rotate the first crankshaft CR1.

[0029] Next, a driving device according to a modified example or another embodiment will be described. In the modified example and another embodiment described below, the same parts as those in the first embodiment described above are given the same reference numerals, and detailed explanations thereof will be omitted or simplified, and the detailed explanation will be centered on the parts that are different from the first embodiment.

[0030] (First Modification) FIG. 8 is a side view of a drive mechanism of a drive device according to a first modified example. According to the first modified example, the order of arrangement of the piston, slider, and counterweight in the X direction is different from that of the first embodiment. As shown in Fig. 8, according to the first modified example, in the first journal portion JA1, the connecting rod CN1, the first slider S1, and the first internal counterweight IW1 are arranged in this order from the base portion BA in the X direction. In the second journal portion JA2, the connecting rod CN2, the second slider S2, and the second internal counterweight IW2 are arranged in this order from the base portion BA in the X direction.

[0031] (Second Modification) FIG. 9 is a side view of a drive mechanism of a drive device according to a second modified example. 9, according to the second modified example, in the first journal portion JA1, the first slider S1, the first internal counterweight IW1, and the connecting rod CN1 are arranged in this order in the X direction from the base portion BA. In the second journal portion JA2, the second slider S2, the second internal counterweight IW2, and the connecting rod CN2 are arranged in this order in the X direction from the base portion BA.

[0032] (Third Modification) FIG. 10 is a side view of a drive mechanism of a drive device according to a third modified example. 10, according to the third modified example, in the first journal portion JA1, the first inner counterweight IW1, the first slider S1, and the connecting rod CN1 are arranged in this order from the base portion BA to the X direction. In the second journal portion JA2, the second inner counterweight IW2, the second slider S2, and the connecting rod CN2 are arranged in this order from the base portion BA to the X direction.

[0033] (Fourth Modification) FIG. 11 is a side view of a drive mechanism of a drive device according to a fourth modified example. 11, according to the fourth modified example, in the first journal portion JA1, the first slider S1, the connecting rod CN1, and the first internal counterweight IW1 are arranged in this order in the X direction from the base portion BA. In the second journal portion JA2, the second slider S2, the connecting rod CN2, and the second internal counterweight IW2 are arranged in this order in the X direction from the base portion BA. In the first to fourth modified examples, the other configurations of the drive mechanism are the same as those of the drive mechanism of the first embodiment described above. However, the installation positions of the first cylinder and the second cylinder are adjusted according to the arrangement positions of the first piston P1 and the second piston P2. In the first to fourth modified examples, the same effects as those of the first embodiment can be obtained.

[0034] In the first embodiment, the drive unit 10 has two cylinders, but is not limited to this and may have one cylinder or three or more cylinders. Second embodiment FIG. 12 is a perspective view showing a drive mechanism of a drive device according to the second embodiment. As shown in the figure, according to the second embodiment, the drive mechanism 20 of the drive device 10 is a single cylinder and has, for example, only a first piston P1. The first piston P1 is connected to a first journal portion JA1 (see FIG. 5) of the second crankshaft CR2 via a connecting rod CN1. A first slider S1 and a first internal counterweight IW1 are attached to the first journal portion JA1. A second slider S2 and a second internal counterweight IW2 are attached to the second journal portion JA2 of the second crankshaft CR2. According to this embodiment, since both the first journal portion JA1 and the second journal portion JA2, which serve as the swing fulcrum, are linearly guided by the guide body, the load acting on the piston is small, and stable, extremely low vibration operation can be achieved even in the case of a single-cylinder drive mechanism 20. At the same time, the single-cylinder configuration allows the drive unit 10 to be made more compact.

[0035] Third embodiment FIG. 13 is a perspective view showing a drive mechanism of a drive device according to a third embodiment. As shown in the figure, according to the third embodiment, the drive mechanism 20 of the drive device 10 is a three-cylinder engine, and further includes a third piston P3. The third piston P3 is connected to a first journal portion JA1 (see FIG. 5) of the second crankshaft CR2 via a connecting rod CN3. A base end portion of the connecting rod CN3 is common to, i.e., is formed integrally with, a base end portion of the connecting rod CN1. With the linear motion of the first journal portion JA1, the first piston P1 and the third piston P3 are linearly moved integrally in the Y direction. In one example, the third piston P3 has a smaller diameter than the first piston P1 and the same diameter as the second piston P2.

[0036] (Fourth embodiment) 14 is a perspective view showing a drive mechanism of a drive device according to a fourth embodiment. As shown in the figure, according to the fourth embodiment, the drive mechanism 20 of the drive device 10 is a four-cylinder engine, and further includes a fourth piston P4. The fourth piston P4 is connected to a second journal portion JA2 of the second crankshaft CR2 via a connecting rod CN4. A base end portion of the connecting rod CN4 is common to, i.e., is formed integrally with, a base end portion of the connecting rod CN2. With the linear motion of the second journal portion JA2, the second piston P2 and the fourth piston P4 are linearly moved integrally in the Z direction. In one example, the fourth piston P4 has a larger diameter than the second piston P2 and the same diameter as the first piston P1.

[0037] Fifth embodiment 15 is a perspective view showing a drive mechanism of a drive device according to the fifth embodiment. Note that Fig. 15 is a perspective view of the drive mechanism 20 seen from the opposite direction to that of Fig. 14. As shown in the figures, according to the fifth embodiment, the drive mechanism 20 of the drive unit 10 is configured with four cylinders, similar to the fourth embodiment. In this embodiment, the third piston P3 is a piston having a larger diameter than the second piston P2 and the same diameter as the first piston P1. The fourth piston P4 is a piston having a smaller diameter than the first piston P1 and the same diameter as the second piston P2. That is, the large-diameter first piston P1 and the third piston P3 are connected to each other via integral connecting rods CN1 and CN3, and are moved up and down linearly in the Y direction. The small-diameter second piston P2 and the fourth piston P4 are connected to each other via integral connecting rods CN2 and CN4, and are moved up and down linearly in the Z direction.

[0038] In the third to fifth embodiments, other configurations of the drive mechanism 20 are similar to those of the drive mechanism 20 in the first embodiment. Also in the three-cylinder or four-cylinder drive devices shown in the third to fifth embodiments, the same operational effects as those of the drive device according to the first embodiment can be obtained.

[0039] Sixth embodiment FIG. 16 is an oblique view showing the drive mechanism of the drive device in the sixth embodiment, FIG. 17 is an oblique view of the drive mechanism from a different direction, FIG. 18 is one side view of the drive device in the sixth embodiment with a part of the housing cut away, and FIG. 19 is another side view of the drive device in the sixth embodiment with a part of the housing cut away. According to the sixth embodiment, instead of the annular sliders, sliders S1, S2 of another shape, here rectangular, are used.

[0040] As shown in FIG. 17 and FIG. 18, the first slider S1 is formed of a rectangular plate material and has a circular inner hole into which the first journal portion JA1 of the second crankshaft CR2 is fitted, and four side surfaces perpendicular to each other. Two of the four side surfaces, which are parallel to each other and face each other and extend linearly in the Y direction, form a pair of guide surfaces GA1 and GA2 of the first slider S1. According to this embodiment, the first slider S1 is formed so as to be separable into two parts at the position of a division surface D1 extending in the Y direction. The division surface D1 is an uneven surface with unevenness arranged in the X direction, and prevents the two parts from shifting in the X direction when the two parts are combined and the division surfaces are joined together. The first slider S1 is attached to the outer circumferential surface of the first journal portion JA1 via a bearing, and is located in a plane perpendicular to the central axis of the first journal portion JA1. 18, the first slider S1 is located between the guide plates 30A and 30B of the first guide body 30. The first slider S1 is sandwiched between the guide surfaces 30a and 30b, and the guide surfaces GA1 and GA2 of the first slider S1 are in contact with the guide surfaces 30a and 30b, respectively. As a result, the first slider S1 is guided in the Y direction by the guide surfaces 30a and 30b when it makes a linear motion in the Y direction.

[0041] As shown in FIG. 16 and FIG. 19, the second slider S2 is formed of a rectangular plate material and has a circular inner hole into which the second journal portion JA2 of the second crankshaft CR2 is fitted, and four side surfaces perpendicular to each other. Of the four side surfaces, two side surfaces that face each other in parallel and extend linearly in the Z direction constitute a pair of guide surfaces GB1, GB2 of the second slider S2. According to this embodiment, the second slider S2 is formed so as to be separable into two parts at the position of a division surface D2 extending in the Z direction. The division surface D2 is an uneven surface with unevenness arranged in the X direction, and prevents the two parts from shifting in the X direction when the two parts are combined and the division surfaces are joined together. The second slider S2 is attached to the outer circumferential surface of the second journal portion JA2 via a bearing, and is located in a plane perpendicular to the central axis of the second journal portion JA2.

[0042] 19, the second slider S2 is located between the guide plates 32A and 32B of the second guide body 32. The second slider S2 is sandwiched between the guide surfaces 32a and 32b, and the guide surfaces GB1 and GB2 of the second slider S2 are in contact with the guide surfaces 32a and 32b, respectively. As a result, the second slider S2 is guided in the Z direction by the guide surfaces 32a and 32b when it makes a linear motion in the Z direction.

[0043] In the sixth embodiment, other configurations of the drive mechanism 20 are similar to those of the drive mechanism 20 in the first embodiment. In the sixth embodiment, the same effects as those of the first embodiment can be obtained. Furthermore, by configuring the slider to be separable, the assembly of the slider is improved. The slider only needs to have two side surfaces (guide surfaces) that are parallel to each other and face each other, and may have any other shape other than a rectangular shape.

[0044] (Modification of the guide plate) 6 and 7, the first guide body 30 that guides the linear motion of the first slider S1 in the Y direction includes guide plates 30A and 30B. The guide plate 30A is provided to stand approximately perpendicular to the bottom wall 12a and the side wall 12e of the housing 12. The guide plate 30B is provided to stand approximately perpendicular to the second top wall 13b and the third side wall 12d of the housing 12. The second guide body 32, which guides the linear motion of the second slider S2 in the Z direction, includes guide plates 32A and 32B. The guide plate 32A is provided to stand approximately perpendicular to the bottom wall 12a and the side wall 12d of the housing 12. The guide plate 32B is provided to stand approximately perpendicular to the first top wall 13a and the fourth side wall 12e of the housing 12.

[0045] Each of the guide plates 30A, 30B and the guide plates 32A, 32B in the above-described embodiment is integrally formed with the housing 12. For example, at least one of guide plates 30A, 30B and guide plates 32A, 32B may be configured as a member separate from housing 12, and this member may be removably fixed to housing 12 by fastening with bolts or the like.

[0046] 20 to 23 show examples of guide plates 30C, 32C configured separately from the housing 12. When only one of the guide plates 30C, 32C is shown, the description will be given with reference to the one shown in the drawing, but the other has the same configuration.

[0047] 20 and 21, for example, the guide plates 30A and 30B are integrated as a guide member 30C having a circular outer circumferential shape when viewed in the axial direction of the rotation shaft including the main shafts M1 and M2.

[0048] The guide member 30C has an oval guide hole 30D that is long in one direction (Y direction, up-down direction in the figure) when viewed from the axial direction of the rotating shaft. The inner peripheral edge of the guide hole 30D has a pair of straight portions 30ta, 30tb that face each other in the short side direction (Z direction, left-right direction in the figure). The pair of straight portions 30ta, 30tb constitute the guide surfaces 30a, 30b. The first slider S1 moves linearly within the overall length range of the pair of straight portions 30ta, 30tb.

[0049] The inner peripheral edge of the guide hole 30D forms a pair of arcuate portions 30e1, 30e2 facing each other in the longitudinal direction. The pair of arcuate portions 30e1, 30e2 are located outside the range of linear motion of the first slider S1. For example, the guide member 30C includes fastening portions 30f for fixing to the housing 12 on both short-side sides of each of the arcuate portions 30e1, 30e2 of the guide hole 30D. The fastening portions 30f are detachably fixed to corresponding portions of the housing 12 by fastening using bolts along the axial direction of the rotation shaft.

[0050] That is, the driving device 10 of this modified example includes a housing 12, main shafts M1, M2 having a first central axis C1, and an eccentric shaft M3 having a second central axis C2 parallel to the first central axis C1 and positioned eccentrically with respect to the main shafts M1, M2. A first crankshaft CR1 is provided in which both axial ends of the main shafts M1, M2 are supported by the housing 12 so as to be rotatable about the first central axis C1. A second crankshaft CR2 is supported by the eccentric shaft M3 so as to be rotatable about the second central axis C2, and includes a first journal portion JA1 eccentric in one direction with respect to the second central axis C2 and a second journal portion JA2 eccentric in the other direction with respect to the second central axis C2. The actuator comprises a first slider S1 rotatably mounted on a journal portion JA1, a second slider S2 rotatably mounted on the second journal portion JA2, a first moving body (first piston P1, connecting rod CN1) rotatably connected to the first journal portion JA1 and moving linearly in a first direction (Y direction) perpendicular to the first central axis C1 in response to movement of the first journal portion JA1, a first guide body 30 provided in the housing 12 and guiding the movement of the first slider S1 along the first direction, and a second guide body 32 provided in the housing 12 and guiding the movement of the second slider S2 along a second direction (Z direction) perpendicular to the first central axis C1 and perpendicular to the first direction. At least one of the first guide body 30 and the second guide body 32 is formed as a separate body from the housing 12, and is detachably fixed to the housing 12 by fastening with bolts.

[0051] Although the linear portions 30ta and 30tb of the first guide body 30 are hardly subjected to a load caused by the movement of the first slider S1, the linear portions 30ta and 30tb are subjected to a load caused by the movement of the second slider S2, which causes friction and rattling. The second guide body 32 has a similar problem. In contrast, according to the above configuration, the first guide body 30 that guides the movement of the first slider S1 is configured as a separate body from the housing 12 and is detachably fixed to the housing 12 with bolts, so that the first guide body 30 can be replaced when worn or damaged, and the movement of the first slider S1 is maintained in a good condition. This makes it possible to provide a drive device that meets the demand for maintaining good operation for a long period of time even when a complex mechanism such as the two-axis oscillating linear drive mechanism 20 is adopted.

[0052] Figure 22 shows a guide member 30C' configured to be divided into two in the short side direction (Z direction, left and right direction in the figure) compared to the guide member 30C in Figure 21. With this configuration, each part is made smaller, making it easier to manufacture the guide member 30C', and it becomes possible to assemble the first slider S1 by sandwiching it between the divided bodies of the guide member 30C', thereby increasing the degree of freedom in assembling the guide member 30C'.

[0053] Since the guide members 30C, 30C' are fixed to the housing 12 using bolts extending in the axial direction, repeated load input from the first slider S1 to the guide surfaces 30a, 30b may cause the guide members 30C, 30C' to shift along the fastening surfaces between them and the housing 12, and eventually a load perpendicular to the bolts may continue to be applied, which may result in damage.

[0054] In response to this, it is possible to adopt a configuration in which the guide members 32Da and 32Db shown in Fig. 23 are fixed to the housing 12 using bolts perpendicular to the axial direction (more specifically, bolts perpendicular to the guide surfaces 32a and 32b). For convenience of illustration, guide members 32Da and 32Db that guide the movement of the second slider S2 are shown in Fig. 23, but the guide member that guides the first slider S1 is also assumed to have a similar configuration.

[0055] In this case, the direction of the load applied from the second slider S2 to the guide surfaces 32a, 32b is parallel to the axial direction of the bolt, preventing the application of a load perpendicular to the bolt. The fastening surfaces of the guide members 32Da, 32Db and the housing 12 butt against each other in the axial direction of the bolt (the load input direction to the guide surfaces 32a, 32b) and receive the vertical load on the guide surfaces 32a, 32b. This also prevents the input of a vertical load to the bolt, suppressing damage to the bolt.

[0056] The fastening portions 32d1, 32d2 of the guide members 32Da, 32Db each have a bolt insertion hole. The bolt insertion hole opens into the guide surfaces 32a, 32b or their extended portions. A seat is formed on the guide surface 32a, 32b side of the bolt insertion hole into which the head of the bolt is recessed. This prevents interference between the second slider S2 and the bolt. There is no offset in the X direction between the guide surfaces 32a, 32b and the bolt, and even if a load is input from the second slider S2 to the guide surfaces 32a, 32b, the guide members 32Da, 32Db will not tilt in the X direction.

[0057] (Modification of slider) 24(a), the first slider S1 of the sixth embodiment is formed of a rectangular plate material. Although not shown, the second slider S2 has a similar structure. The first slider S1 has four side surfaces arranged perpendicular to each other. Of the four side surfaces, two side surfaces extending along the Y direction constitute a pair of guide surfaces GA1, GA2 of the first slider S1. A slider oil hole h1 is formed through the center of the guide surfaces GA1, GA2 extending in the Y direction, leading to an inner hole into which the first journal portion JA1 is fitted. Lubricating oil can be supplied from the first journal portion JA1 side to the guide surfaces GA1, GA2 through the slider oil hole h1. The first slider S1 has a total length of about 100 mm in each of the Y direction and the Z direction, and a thickness in the X direction (axial direction) of about 30 mm. Up to this point, the configuration is the same as that of the first slider S1 of the sixth embodiment.

[0058] The first slider S1 of the modified example has guide surfaces GA1 and GA2 extending in the Y direction, which are provided with a convex curvature (radius of approximately 800 mm) on the outer periphery side when viewed from the axial direction. In other words, the first slider S1 includes arc-shaped portions r1 having a convex curvature on the outer side in the width direction on the guide surfaces GA1 and GA2 located on both sides in the width direction perpendicular to the moving direction of the slider itself.

[0059] That is, the driving device 10 of this modified example includes a housing 12, main shafts M1, M2 having a first central axis C1, and an eccentric shaft M3 having a second central axis C2 parallel to the first central axis C1 and positioned eccentrically with respect to the main shafts M1, M2. A first crankshaft CR1 is provided in which both axial ends of the main shafts M1, M2 are supported by the housing 12 so as to be rotatable about the first central axis C1. A second crankshaft CR2 is supported by the eccentric shaft M3 so as to be rotatable about the second central axis C2, and includes a first journal portion JA1 eccentric in one direction with respect to the second central axis C2 and a second journal portion JA2 eccentric in the other direction with respect to the second central axis C2. The actuator comprises a first slider S1 rotatably mounted on a journal portion JA1, a second slider S2 rotatably mounted on the second journal portion JA2, a first moving body (first piston P1, connecting rod CN1) rotatably connected to the first journal portion JA1 and moving linearly in a first direction (Y direction) perpendicular to the first central axis C1 in response to movement of the first journal portion JA1, a first guide body 30 provided in the housing 12 and guiding the movement of the first slider S1 along the first direction, and a second guide body 32 provided in the housing 12 and guiding the movement of the second slider S2 along a second direction (Z direction) perpendicular to the first central axis C1 and perpendicular to the first direction. At least one of the first slider S1 and the second slider S2 is plate-shaped with its thickness in the axial direction, and has a pair of side portions (guide surfaces GA1, GA2) extending along the movement direction on both sides in the width direction perpendicular to its movement direction when viewed from the axial direction, and each side portion includes an arc-shaped portion r1 having a curvature that is convex outward in the width direction. Note that the arc-shaped portion r1 is a portion having a sufficiently small curvature, unlike the rounded chamfers of the corners of the first slider S1.

[0060] With this configuration, compared to the case where the guide surfaces GA1, GA2 extend linearly when viewed in the axial direction, the contact area between the guide surfaces GA1, GA2 of the first slider S1 and the guide surfaces 30a, 30b of the first guide body 30 is reduced, making it possible to prevent malfunction of the drive mechanism 20 due to contact resistance between the first slider S1 and the first guide body 30. As a result, it is possible to provide a drive device that meets the demand for maintaining good operation for a long period of time even when a complex mechanism such as the two-axis oscillating linear drive mechanism 20 is adopted.

[0061] 24(b) shows another modified example of the first slider S1. In this modified example, the guide surfaces GA1 and GA2 of the first slider S1 form an arc-shaped portion r1 having a convex curvature (radius 800 mm) on the outer periphery side when viewed from the axial direction, and also form a straight portion (flat portion) r2 along the Y direction in an intermediate range including the center of the arc-shaped portion r1 in the Y direction.

[0062] According to this configuration, by making the ranges on both sides of the guide surfaces GA1 and GA2 in the Y direction into the arc-shaped portions r1, it is possible to obtain the effect of reducing the contact area between the guide surfaces GA1 and GA2 of the first slider S1 and the guide surfaces 30a and 30b of the first guide body 30. On the other hand, by making the intermediate range of the guide surfaces GA1 and GA2 in the Y direction into the flat straight portion r2, it is easy to maintain the oil film between the guide surfaces GA1 and GA2 of the first slider S1 and the guide surfaces 30a and 30b of the first guide body 30, and the movement of the first slider S1 can be made smoother. Since the oil hole h1 is opened in the intermediate range of the guide surfaces GA1 and GA2 in the Y direction, it is easy to receive the supply of lubricating oil, and in this respect, the movement of the first slider S1 can be made smoother.

[0063] For example, the gap (minimum value) between the guide surfaces GA1, GA2 of the first slider S1 and the guide surfaces 30a, 30b of the first guide body 30 is larger than the maximum tolerance of the eccentricity (the distance between the central axes C2, CG1) of the first journal portion JA1 of the second crankshaft CR2. This configuration also makes it possible to prevent malfunction of the drive mechanism 20 due to contact resistance between the first slider S1 and the first guide body 30.

[0064] (Modification of journal part) 25 and 26 show modified examples of the first journal portion JA1 and the second journal portion JA2 (modified examples of the second crankshaft CR2). The second journal portion JA2 has the same configuration as the first journal portion JA1 shown in FIG. The first journal portion JA1 and the second journal portion JA2 are configured as separate cylindrical members.

[0065] In the above-described embodiment, a disk-shaped base portion BA is provided between the first journal portion JA1 and the second journal portion JA2 in the axial direction (see FIG. 3), but in this modified example, the base portion BA is eliminated. In this modified example, the inner end faces t1, t2 of the first journal portion JA1 and the second journal portion JA2 on the inner side in the axial direction of the second crankshaft CR2 are butted against each other and connected to each other.

[0066] 31 to 34, a rod-shaped eccentric shaft M3 is inserted into the through hole 22 that penetrates the first journal portion JA1 and the second journal portion JA2. The central axes (central axes CG1, CG2) of the first journal portion JA1 and the second journal portion JA2 are offset from the central axis (second central axis C2) of the eccentric shaft M3 by the same amount in an eccentric direction perpendicular to the second central axis C2. Hereinafter, a direction perpendicular to the axial direction and the eccentric direction is referred to as an eccentricity perpendicular direction. For example, a pair of lightening holes 22a that are sector-shaped when viewed in the axial direction are formed on either side of the center in the eccentricity perpendicular direction in the region opposite the through hole 22 in the eccentricity direction in the first journal portion JA1 and the second journal portion JA2.

[0067] The first journal portion JA1 and the second journal portion JA2 are each provided with a connecting portion 23 for connecting the first journal portion JA1 and the second journal portion JA2 to each other on both sides of the through hole 22 in the direction perpendicular to the eccentricity. In each of the first journal portion JA1 and the second journal portion JA2, the connecting portion 23 on one side in the direction perpendicular to the eccentricity forms a bolt insertion hole along the axial direction, and the connecting portion 23 on the other side in the direction perpendicular to the eccentricity forms a nut hole along the axial direction.

[0068] In the bolt insertion hole and the nut hole of the connecting portion 23, a counterbore of the same diameter is formed on the inner end faces t1, t2 of the first journal portion JA1 and the second journal portion JA2. A cylindrical collar 26 is inserted into the counterbore that faces each other in the axial direction. A knock hole into which a knock pin 27 is inserted is formed adjacent to the bolt insertion hole and the nut hole. A work hole for machining each hole is formed on the opposite side of the bolt insertion hole and the nut hole in the axial direction in the first journal portion JA1 and the second journal portion JA2. A connecting bolt can be inserted into the bolt insertion hole through this work hole.

[0069] When connecting the first journal portion JA1 and the second journal portion JA2, first, the collar 26 and the knock pin 27 are inserted into one of the inner end faces t1, t2, and the inner end faces t1, t2 are opposed to each other and butted against each other. As a result, the collar 26 and the knock pin 27 are inserted into the seat bores and knock holes that face each other in the axial direction, and the first journal portion JA1 and the second journal portion JA2 are positioned relative to each other. In this state, a connecting bolt is inserted into a bolt insertion hole of one of the first journal portion JA1 and the second journal portion JA2, and the connecting bolt is screwed into a nut hole of the other and tightened, thereby connecting the first journal portion JA1 and the second journal portion JA2 together in the axial direction.

[0070] A pair of weight connecting parts 28 are formed at the axial intermediate parts of the first journal part JA1 and the second journal part JA2, sandwiching the center in the direction perpendicular to the eccentricity. The weight connecting parts 28 are configured to attach separate inner counterweights IW1, IW2, and include a bolt insertion hole parallel to the eccentricity direction and a concave shape that cuts out the outer circumferential surface of the journal part on both sides of the bolt insertion hole.

[0071] That is, the driving device 10 of this modified example includes a housing 12, main shafts M1, M2 having a first central axis C1, and an eccentric shaft M3 having a second central axis C2 parallel to the first central axis C1 and positioned eccentrically with respect to the main shafts M1, M2. A first crankshaft CR1 is provided in which both axial ends of the main shafts M1, M2 are supported by the housing 12 so as to be rotatable about the first central axis C1. A second crankshaft CR2 is supported by the eccentric shaft M3 so as to be rotatable about the second central axis C2, and includes a first journal portion JA1 eccentric in one direction with respect to the second central axis C2 and a second journal portion JA2 eccentric in the other direction with respect to the second central axis C2. The actuator comprises a first slider S1 rotatably mounted on a journal portion JA1, a second slider S2 rotatably mounted on the second journal portion JA2, a first moving body (first piston P1, connecting rod CN1) rotatably connected to the first journal portion JA1 and moving linearly in a first direction (Y direction) perpendicular to the first central axis C1 in response to movement of the first journal portion JA1, a first guide body 30 provided in the housing 12 and guiding the movement of the first slider S1 along the first direction, and a second guide body 32 provided in the housing 12 and guiding the movement of the second slider S2 along a second direction (Z direction) perpendicular to the first central axis C1 and perpendicular to the first direction. The first journal portion JA1 and the second journal portion JA2 are formed as separate bodies and are integrally connected in the axial direction to form the second crankshaft CR2.

[0072] According to this configuration, the first journal portion JA1 and the second journal portion JA2, which are separate from each other, are connected in the axial direction to form the second crankshaft CR2, which facilitates the manufacture and processing of the first journal portion JA1 and the second journal portion JA2. The first journal portion JA1 and the second journal portion JA2 are connected by fastening them with a bolt along the axial direction in a state in which their relative positions are determined by the collar 26 and the knock pin 27 along the axial direction, which facilitates the assembly of the second crankshaft CR2. This makes it possible to provide a drive device that meets the demand for easy manufacture and assembly even when a complex mechanism such as the biaxial oscillating linear drive mechanism 20 is adopted.

[0073] Referring to FIG. 37, the second crankshaft CR2 has a through hole 22 that passes through the first journal portion JA1 and the second journal portion JA2 in the axial direction. An independent rod-shaped eccentric shaft M3 is inserted into the through hole 22. Both axial ends of the eccentric shaft M3 form protruding shafts mt that protrude axially outward beyond the first journal portion JA1 and the second journal portion JA2. A first counterweight W1 and a second counterweight W2 are attached to each protruding shaft mt. That is, in this modified example, the first counterweight W1 and the second counterweight W2 are configured separately from the eccentric shaft M3.

[0074] 35(a) and 35(b), the first counterweight W1 and the second counterweight W2 are integrated with the main shaft M1 or M2 on the same axial side, respectively. The first counterweight W1 and the second counterweight W2 are integrally connected to the protruding shaft mt on the same axial side via a rotation-preventing pin along the axial direction and a fixing bolt along the radial direction. This makes it possible to provide a drive device that meets the demand for easy manufacturing and assembly even when a complex mechanism such as the two-axis oscillating linear drive mechanism 20 is adopted.

[0075] In the above modified example, both the first counterweight W1 and the second counterweight W2 are configured separately from the eccentric shaft M3, but as shown in FIG. 36, one of the first counterweight W1 and the second counterweight W2 (the second counterweight W2 in the figure) may be configured integrally with the eccentric shaft M3 (integrally formed from the same material).

[0076] 31 and 33, the outer periphery of the eccentric shaft M3 is formed with a shaft outer periphery surface ma in contact with the inner periphery of the through hole 22 of the first journal portion JA1 and the second journal portion JA2, annular oil grooves mb, md recessed inwardly from the shaft outer periphery surface ma, and a displacement portion mc recessed flatly into the shaft outer periphery surface ma over a wide range in the axial direction and shallower than the oil grooves mb, md. The protruding shafts mt on both axial sides of each journal portion have a smaller diameter than the shaft outer periphery surface ma.

[0077] Annular corners k1 are formed between the shaft outer peripheral surface ma and the protruding axis mt, between the shaft outer peripheral surface ma and each oil groove mb, md, and between the shaft outer peripheral surface ma and the displacement portion mc, and each of these corners k1 is chamfered to have a tapered surface that is inclined in the axial and radial directions. The first journal portion JA1 and the second journal portion JA2 have a split structure, and if the through hole 22 is misaligned at the opposing inner end faces t1, t2, each corner k1 of the outer periphery of the eccentric shaft M3 is likely to get caught on the opening periphery of the through hole 22, making it difficult to assemble the second crankshaft CR2.

[0078] In this modification, each corner k1 of the eccentric shaft M3 is chamfered to make it difficult for each corner k1 of the eccentric shaft M3 to get caught on the opening periphery of the through hole 22. The dimension of this chamfer is set, for example, to about twice the tolerance of the center position of each through hole 22 of the first journal portion JA1 and the second journal portion JA2. This makes it difficult for each corner k1 of the eccentric shaft M3 to get caught even if the deviation of the axial center position of each through hole 22 becomes maximum. Similar to each corner k1, a peripheral edge k2 of an opening facing the axially outward direction of the second crankshaft CR2 in each through hole 22 of the first journal portion JA1 and the second journal portion JA2 is chamfered to have a tapered shape inclined in the axial and radial directions. A similar chamfer may also be applied to peripheral edge k3 of an opening facing the axially inward direction of the second crankshaft CR2 in each through hole 22 of the first journal portion JA1 and the second journal portion JA2, which face each other.

[0079] (Modification of the internal counterweight) As shown in Figures 27 and 28, the first internal counterweight IW1 of the modified example is configured as a separate member from the first journal portion JA1. Although not shown, the second internal counterweight IW2 of the modified example is also configured as a separate member from the second journal portion JA2. Below, the first journal portion JA1 and the first internal counterweight IW1 will be described as an example, but the second journal portion JA2 and the second internal counterweight IW2 also have the same configuration.

[0080] If the first journal portion JA1 and the second journal portion JA2 are cylindrical members, the first inner counterweight IW1 and the second inner counterweight IW2 must be provided separately from the corresponding journal portion JA1 or JA2 and then attached to the corresponding journal portion JA1 or JA2 by bolting or the like. In this case, for example, a structure is conceivable in which an annular body is integrally formed around the entire outer periphery of the journal portion with the separate counterweight, and the separate counterweight is attached to the journal portion by fitting the annular body to the outer periphery of the journal portion. However, the annular body does not function as a counterweight and is an obstacle to making the separate counterweight smaller and lighter.

[0081] The inner counterweight IW1 in Figs. 27 and 28 does not have an annular body, but has only a sector-shaped eccentric weight (weight body) W3 that protrudes outward from the outer circumferential surface of the journal part JA1, thereby making the inner counterweight IW1 smaller and lighter. The eccentric weight W3 is fixed to the journal part JA1 using a pair of connecting bolts BC corresponding to the pair of weight connecting parts 28 described above. The inner counterweight IW1 has an arc-shaped arc part W4 that follows the outer circumferential surface of the journal part JA1. The arc part W4 does not extend over the entire circumference of the outer circumferential surface of the journal part JA1, but only contacts the area where the eccentric weight W3 is provided in the circumferential direction, and the remaining area in the circumferential direction has an open part that is divided in the circumferential direction. The inner counterweight IW1 does not form an annular body that extends over the entire circumference of the journal part JA1, but cuts out at least a part in the circumferential direction to form an open part, forming a non-contact area with the journal part JA1.

[0082] That is, the driving device 10 of this modified example includes a housing 12, main shafts M1, M2 having a first central axis C1, and an eccentric shaft M3 having a second central axis C2 parallel to the first central axis C1 and positioned eccentrically with respect to the main shafts M1, M2. A first crankshaft CR1 is provided in which both axial ends of the main shafts M1, M2 are supported by the housing 12 so as to be rotatable about the first central axis C1. A second crankshaft CR2 is supported by the eccentric shaft M3 so as to be rotatable about the second central axis C2, and includes a first journal portion JA1 eccentric in one direction with respect to the second central axis C2 and a second journal portion JA2 eccentric in the other direction with respect to the second central axis C2. The actuator comprises a first slider S1 rotatably mounted on a journal portion JA1, a second slider S2 rotatably mounted on the second journal portion JA2, a first moving body (first piston P1, connecting rod CN1) rotatably connected to the first journal portion JA1 and moving linearly in a first direction (Y direction) perpendicular to the first central axis C1 in response to movement of the first journal portion JA1, a first guide body 30 provided in the housing 12 and guiding the movement of the first slider S1 along the first direction, and a second guide body 32 provided in the housing 12 and guiding the movement of the second slider S2 along a second direction (Z direction) perpendicular to the first central axis C1 and perpendicular to the first direction. Separate inner counterweights IW1, IW2 are removably attached to at least one of the first journal portion JA1 and the second journal portion JA2, and the inner counterweights IW1, IW2 have an arc portion W4 that extends along the outer peripheral surface of the journal portion to which they are attached in the circumferential direction, in the range in which the eccentric weight W3 is provided, and the range in which the eccentric weight W3 is not provided is an open portion that is divided in the circumferential direction.

[0083] According to this configuration, the inner counterweights IW1, IW2 separate from the journal part contact only a part of the outer circumferential surface of the journal part, and the remaining range in the circumferential direction is left as an open part and is not in contact with the journal part, so that the separate inner counterweights IW1, IW2 can be made smaller and lighter than when the separate inner counterweights IW1, IW2 have an annular body that fits around the entire circumference of the journal part. This makes it possible to provide a drive device that meets the demand for easy manufacturing and assembly even when a complex mechanism such as the two-axis oscillating linear drive mechanism 20 is adopted.

[0084] In the examples of Figures 27 and 28, the arc portion W4 of the inner counterweight IW1 is a surface that follows the outer peripheral surface of the journal portion JA1 (a surface that follows the circumferential direction), and when the drive unit 10 accelerates or decelerates its operation, the inner counterweight IW1 may shift along the outer peripheral surface of the journal portion JA1, which may cause play in the inner counterweight IW1 or wear on the contact surface.

[0085] 29 and 30, legs 29 extend from the arc portion W4 of the inner counterweight IW1 toward the journal portion JA1 along each connecting bolt BC, and these legs 29 are inserted into recesses in the weight connecting portion 28 formed on the outer periphery of the journal portion JA1. At least one of the inner counterweight IW1 and the journal portion JA1 has a surface W5 that intersects with the circumferential direction of the journal portion JA1. If the counterweight IW1 does not move due to the tightening of the connecting bolts BC, the surface W5 does not come into contact with anything, and the structure of the weight connecting portion 28 can suppress circumferential displacement of the counterweights IW1 and IW2.

[0086] Therefore, it is possible to prevent the counterweight IW1 from shifting along the outer circumferential surface of the journal portion JA1 even when accelerating or decelerating the operation of the drive unit 10, and to suppress rattle and wear of the counterweight IW1. This makes it possible to provide a drive unit that meets the demand for maintaining good operation for a long period of time even when a complex mechanism such as the two-axis oscillating linear drive mechanism 20 is adopted.

[0087] (Second crankshaft oil supply structure) As shown in Fig. 37, the eccentric shaft M3 of the second crankshaft CR2 is hollow and has an internal space extending along the axis. The internal space of the eccentric shaft M3 serves as an in-shaft oil passage 34 for supplying lubricating oil to each moving part of the second crankshaft CR2. A plurality of oil holes 41-44 are formed in the eccentric shaft M3 and extend radially outward from the in-shaft oil passage 34. Oil is supplied to each moving part such as each journal portion through the plurality of oil holes 41-44.

[0088] The drive unit 10 uses the lower part of the housing 12 as an oil pan, and supplies oil stored in this oil pan to each part of the drive unit 10 to lubricate the moving parts. The main shaft M2 on the left side of the figure is connected to a drive shaft 51 (see FIG. 43) of an electric motor 50 which is the drive source of the drive unit 10. An eccentric shaft 36 eccentric to the main shaft M2 is provided at the base end (the end on the counterweight IW2 side) of the main shaft M2. The eccentric shaft 36 generates the driving force of an oil pump (not shown). The oil discharged by the oil pump reaches an oil passage formed in the eccentric shaft 36 and is supplied to one end of the shaft oil passage 34 through an inlet oil hole 37 inclined to the central axis C2. The oil flowing through the shaft oil passage 34 to the other end is returned to the housing 12 through an outlet oil hole 38 formed in the counterweight W1 on the right side of the figure.

[0089] 33, on the outer periphery of the eccentric shaft M3, in addition to the shaft outer periphery surface ma, an outer oil groove mb, a displacement portion mc, and an inner oil groove md are formed in that order from the outside in the axial direction. A first oil hole 41 opens into the outer oil groove mb, a second oil hole 42 opens into the inner oil groove md, and a third oil hole 43 opens into the displacement portion mc. A fourth oil hole 44 opens into the shaft outer periphery surface ma located in the axial center of the eccentric shaft M3.

[0090] The inner peripheral surfaces of the first journal portion JA1 and the second journal portion JA2 are in contact with the outer peripheral surface ma of the eccentric shaft M3 on both axial sides thereof. A first slider S1 and a second slider S2, a first inner counterweight IW1 and a second inner counterweight IW2, a first connecting rod CN1 and a second connecting rod CN2 are attached to the outer peripheral portions of the first journal portion JA1 and the second journal portion JA2 in this order from the outside in the axial direction of the eccentric shaft M3.

[0091] 38, the first journal portion JA1 and the second journal portion JA2 are formed with a plurality of journal oil holes 35a, 35b extending from the through hole 22 to the outer peripheral surface. Each of the journal oil holes 35a, 35b includes a first journal oil hole 35a which overlaps in the axial direction with the outer oil groove mb of the eccentric shaft M3 and the first slider S1 and the second slider S2, and a second journal oil hole 35b which overlaps in the axial direction with the inner oil groove md of the eccentric shaft M3 and the first connecting rod CN1 and the second connecting rod CN2.

[0092] As a result, the oil that reaches the shaft inner oil passage 34 is supplied to the first slider S1, the second slider S2, and the first connecting rod CN1, the second connecting rod CN1 through the first oil hole 41, the second oil hole 42, the outer oil groove mb, the inner oil groove md, and the first journal oil hole 35a, the second journal oil hole 25b. Furthermore, the first slider S1 and the second slider S2 are formed with a slider oil hole h1 that opens into the pair of guide surfaces GA1, GA2. The oil supplied to the first slider S1 and the second slider S2 serves to reduce contact friction with the guide bodies 30, 32.

[0093] The displacement portion mc provides a gap between itself and the inner peripheral surface of each journal portion JA1, JA2, thereby reducing the contact resistance between each journal portion JA1, JA2 and the eccentric shaft M3. The gap formed by the displacement portion mc is filled with lubricating oil to lubricate between each journal portion JA1, JA2 and the eccentric shaft M3. The third oil hole 43 opening into the displacement portion mc has a smaller diameter than the first oil hole 41 and the second oil hole 42 opening into the outer oil groove mb and the inner oil groove md, respectively. This ensures reliable oil supply to each slider S1, S2 and each connecting rod CN1, CN2.

[0094] A fourth oil hole 44 opening in the axial center of the eccentric shaft M3 supplies oil between the pair of journal portions JA1, JA2. Connecting rods CN1, CN2 are supported in the axial middle of each journal portion. Oil is supplied from the fourth oil hole 44 between the pair of adjacent connecting rods CN1, CN2 in the axial center of the eccentric shaft M3.

[0095] That is, the drive unit 10 having the above-mentioned configuration includes a housing 12, main shafts M1, M2 having a first central axis C1, and an eccentric shaft M3 having a second central axis C2 parallel to the first central axis C1 and positioned eccentrically with respect to the main shafts M1, M2, and includes a first crankshaft CR1 in which both axial ends of the main shafts M1, M2 are supported by the housing 12 so as to be rotatable about the first central axis C1, a second crankshaft CR2 in which the first journal portion JA1 is eccentric in one direction with respect to the second central axis C2 and a second journal portion JA2 is eccentric in the other direction with respect to the second central axis C2, and The actuator comprises a first slider S1 rotatably mounted on a first journal portion JA1, a second slider S2 rotatably mounted on the second journal portion JA2, a first moving body (first piston P1, connecting rod CN1) rotatably connected to the first journal portion JA1 and moving linearly in a first direction (Y direction) perpendicular to the first central axis C1 in response to movement of the first journal portion JA1, a first guide body 30 provided in the housing 12 and guiding the movement of the first slider S1 along the first direction, and a second guide body 32 provided in the housing 12 and guiding the movement of the second slider S2 along a second direction (Z direction) perpendicular to the first central axis C1 and perpendicular to the first direction. The eccentric shaft M3 is a hollow shaft, and the internal space of the eccentric shaft M3 serves as an internal oil passage 34 for supplying lubricating oil to the second crankshaft CR2 and the moving parts supported by the second crankshaft CR2. The eccentric shaft M3 is formed with a plurality of oil holes 41-44 which extend radially outward from the internal oil passage 34 and open at the outer periphery of the eccentric shaft M3.

[0096] According to this configuration, lubricating oil can be supplied to the movable parts supported by the eccentric shaft M3 through the in-shaft oil passage 34 and the multiple oil holes 41 to 44 formed in the eccentric shaft M3. This makes it possible to provide a drive device that meets the demand for maintaining good operation for a long period of time even when a complex mechanism such as the two-axis oscillating linear drive mechanism 20 is adopted.

[0097] (Structure of base end of cylinder liner) 39 to 41, the first cylinder 14a and the second cylinder 14b are provided with cylindrical cylinder liners 15, 16 into which the piston P1 or P2 is inserted so as to be capable of reciprocating motion, respectively. The cylinder liners 15, 16 have base ends (one end in the cylinder axial direction) 15a, 16a facing the crank chamber side that houses the crankshafts CR1, CR2 in the crankcase 12.

[0098] Also referring to FIG. 37, in the driving device 10 of the embodiment, the connecting rods CN1 and CN2, the inner counterweights W1 and W2, and the sliders S1 and S2 are assembled in the axial direction in order to the first journal portion JA1 and the second journal portion JA2 of the second countershaft CR2. A snap ring 24 is attached to the axially outer end of the second crankshaft CR2 in the first journal portion JA1 and the second journal portion JA2 to prevent the movable parts assembled to each journal portion from coming off. The reference numeral 25 in the other figures indicates a ring groove to which the snap ring 24 is attached. This prevents the movable parts from coming off from each journal with a simple and compact structure. When the guide member 30C is an integral ring-shaped member (see FIG. 21), the guide member 30C is also assembled to the outer periphery of the slider in advance.

[0099] Furthermore, the eccentric shaft M3 is inserted through the through holes 22 of each journal portion, and the first counterweight W1 and the second counterweight W2 (including the first main shaft M1 and the second main shaft M2) are attached and fixed to the protruding shaft mt of the eccentric shaft M3. In this way, movable parts such as the connecting rods CN1, CN2, the inner counterweights IW1, IW2, and the sliders S1, S2 are assembled to the second crankshaft CR2, and a crankshaft assembly CRA is constructed with the eccentric shaft M3 and the counterweights W1, W2 assembled.

[0100] A corresponding piston is pre-assembled to the small end of each connecting rod CN1, CN2. Generally, when inserting a piston into a cylinder, a cylindrical piston ring compressor is used to reduce the outer diameter of the piston ring, and the piston is inserted into the cylinder from the cylinder head side. However, when inserting the pistons P1, P2, which are part of the crankshaft assembly CRA, into the cylinders 14a, 14b, the pistons P1, P2 are inserted into the cylinders 14a, 14b from the crankcase side, not from the cylinder head side. For this reason, a piston ring compressor cannot be used because it would interfere with other parts.

[0101] In the embodiment, tapered piston ring guide surfaces 15b, 16b that increase in diameter toward the end of the cylinder liners 15, 16 are formed on the inner peripheral side of the base ends 15a, 16a on the crank chamber side of the cylinder liners 15, 16. This makes it possible to insert the pistons P1, P2 into the cylinder liners 15, 16 by axially pushing the pistons P1, P2 into the cylinder liners 15, 16, thereby reducing the diameter of the piston rings along the inclination of the piston ring guide surfaces 15b, 16b, without using a piston ring compressor.

[0102] In particular, in the two-cylinder drive unit 10, after one piston is inserted into a cylinder liner, the other piston is placed coaxially on the base end side of the corresponding cylinder liner while swinging the remaining parts including the connecting rod. In this state, the other piston is inserted axially into the corresponding cylinder liner. At this time, since it is necessary to place the other piston and the cylinder liner coaxially, the counterweights W1, W2 and IW1, IW2 protruding radially from the crankshaft assembly CRA are particularly likely to interfere with the base ends 15a, 16a of the cylinder liners 15, 16.

[0103] In the above configuration, the protruding arc-shaped notches 15c, 16c are formed on both sides in the crankshaft direction (parts where interference with the counterweight is expected) of the base ends 15a, 16a of the cylinder liners 15, 16 on the tip side (cylinder head side) of the cylinder liners 15, 16 as viewed from the crankshaft direction. This makes it possible to insert the pistons P1, P2 of the crankshaft assembly CRA into the corresponding cylinder liners 15, 16 while avoiding interference between the base ends 15a, 16a of the cylinder liners 15, 16 and the counterweight of the crankshaft assembly CRA. By forming the arc-shaped notches 15c, 16c on both sides in the crankshaft direction, rather than simply shortening the base ends 15a, 16a of the cylinder liners 15, 16, it is possible to avoid interference between the cylinder liners 15, 16 and the counterweight while maintaining the effect of compressing the piston rings.

[0104] That is, the drive unit 10 having the above-mentioned configuration includes a housing 12, main shafts M1, M2 having a first central axis C1, and an eccentric shaft M3 having a second central axis C2 parallel to the first central axis C1 and positioned eccentrically with respect to the main shafts M1, M2. The drive unit 10 includes a first crankshaft CR1 in which both axial ends of the main shafts M1, M2 are supported by the housing 12 so as to be rotatable about the first central axis C1, a second crankshaft CR2 in which the first journal portion JA1 is eccentric in one direction with respect to the second central axis C2 and a second journal portion JA2 eccentric in the other direction with respect to the second central axis C2 is supported by the eccentric shaft M3 so as to be rotatable about the second central axis C2, and a first journal portion JA2 eccentrically provided on the first journal portion JA1. The housing 12 includes a slider S1, a second slider S2 rotatably mounted on the second journal portion JA2, a first moving body (first piston P1, connecting rod CN1) rotatably connected to the first journal portion JA1 and linearly moving in a first direction (Y direction) perpendicular to the first central axis C1 in response to movement of the first journal portion JA1, a first guide body 30 provided in the housing 12 and guiding the movement of the first slider S1 along the first direction, a second guide body 32 provided in the housing 12 and guiding the movement of the second slider S2 along a second direction (Z direction) perpendicular to the first central axis C1 and perpendicular to the first direction, and a third guide body 14a (first cylinder 14a) provided in the housing 12 and guiding the linear motion of the first moving body. The third guide body 14a has a first cylinder 14a provided in the housing 12 and extending in the first direction, and the first movable body has a first piston P1 inserted into a cylinder liner 15 of the first cylinder 14a so as to be able to reciprocate in the first direction, and a tapered inner circumferential surface 15b that widens in diameter toward the end side is formed on a base end 15a of the cylinder liner 15 on the housing 12 side, and an arc-shaped notch 15c is formed when viewed from the axial direction of the second crankshaft CR2.

[0105] According to this configuration, by forming tapered inner circumferential surfaces 15b, 16b at the base ends 15a, 16a of the cylinder liners 15, 16, which become wider in diameter toward the end, the tapered inner circumferential surfaces 15b, 16b serve as guide surfaces that compress the piston rings, and the pistons P1, P2 can be inserted into the cylinder liners 15, 16 from the housing 12 side without using a piston ring compressor. Even in a configuration in which movable parts such as connecting rods CN1, CN2, inner counterweights IW1, IW2, and sliders S1, S2 are pre-assembled to the second crankshaft CR2, and the eccentric shaft M3 and counterweights W1, W2 are assembled to form the crankshaft assembly CRA, and then the pistons P1, P2 are inserted into the cylinder liners 15, 16 from the housing 12 side, by forming notches 15b, 16b on both sides in the crankshaft direction of the base ends 15a, 16a of the cylinder liners 15, 16, it is possible to prevent the counterweights from interfering with the base ends 15a, 16a of the cylinder liners 15, 16. This makes it possible to provide a drive device that meets the demand for easy manufacture and assembly even when a complex mechanism such as the two-axis oscillating linear drive mechanism 20 is employed.

[0106] (Connecting rod hollow structure) 44(a) and 44(b), the drive device 10 thus configured includes a housing 12, main shafts M1 and M2 having a first central axis C1, and an eccentric shaft M3 having a second central axis C2 parallel to the first central axis C1 and positioned eccentrically with respect to the main shafts M1 and M2. A first crankshaft CR1 is supported at both axial ends of the main shafts M1 and M2 by the housing 12 so as to be rotatable about the first central axis C1. A second crankshaft CR2 is supported by the eccentric shaft M3 so as to be rotatable about the second central axis C2, and includes a first journal portion JA1 eccentric in one direction with respect to the second central axis C2 and a second journal portion JA2 eccentric in the other direction with respect to the second central axis C2. A first slider S1 is rotatably provided on the first journal portion JA1. A second slider S2 is rotatably provided on the second journal portion JA2. the housing 12 includes a second slider S2 connected to the housing 12, a first moving body (first piston P1, connecting rod CN1) rotatably connected to the first journal portion JA1 and linearly moving in a first direction (Y direction) perpendicular to the first central axis C1 in accordance with the movement of the first journal portion JA1, a second moving body (second piston P2 and connecting rod CN2) rotatably connected to the second journal portion JA2 and linearly moving in a second direction (Z direction) perpendicular to the first central axis C1 and perpendicular to the first direction in accordance with the movement of the second journal portion JA2, a first guide body 30 provided in the housing 12 and guiding the movement of the first slider S1 along the first direction, and a second guide body 32 provided in the housing 12 and guiding the movement of the second slider S2 along a second direction (Z direction) perpendicular to the first central axis C1 and perpendicular to the first direction. The connecting rod CN1 of the first moving body and the connecting rod CN2 of the second moving body have different hollowed-out portions.

[0107] The connecting rod CN1 of the first moving body and the connecting rod CN2 of the second moving body each have a large end 17a, 18a on the journal side and a small end 17b, 18b on the piston side. The rod portion 17c, 18c between the large and small ends of each connecting rod CN1, CN2 has a hollowed-out portion 17d, 18d formed on both sides in the axial direction. By adjusting the shape and depth of each hollowed-out portion 17d, 18d, it is possible to easily achieve a rotational balance of the drive shaft in the drive unit 10 having cylinders with different diameters. This makes it possible to provide a drive device that meets the demand for easy manufacture and assembly even when a complex mechanism such as the two-axis oscillating linear drive mechanism 20 is employed.

[0108] (Connection structure between main shaft and motor drive shaft) 43, an electric motor 50 serving as a drive source for the drive device 10 is disposed on one axial side of the drive device 10. A drive shaft (motor drive shaft) 51 of the electric motor 50 is coaxially connected to a main shaft M2 on one axial side of the drive device 10. The motor drive shaft 51 is coaxially connected to the second main shaft M2 (or the first main shaft M1) using a connector 55.

[0109] The motor drive shaft 51 is hollow and opens on both axial sides of the electric motor 50. The motor drive shaft 51 approaches the main shaft M2 from the outside in the axial direction, and is connected by inserting the main shaft M2 into one axial side. A nut hole that opens into the end face is formed in the main shaft M2. A connector 55 is inserted into the motor drive shaft 51 from the other end.

[0110] 42(a) and 42(b), the connecting device 55 includes a connecting bolt 56 that is screwed and tightened into a nut hole that is formed coaxially along the axis of the main shaft M2, and an expanding washer device 57 that can abut against the reduced diameter portion 52 formed on the inner circumference of the outer shaft from the outside in the axial direction, and that moves multiple movable bodies (split bodies 59a described later) evenly radially outward by tightening the connecting bolt 56.

[0111] The expanding washer device 57 comprises a truncated cone-shaped inner member 58 which forms a seat for receiving the head of the connecting bolt 56 and which forms an outer tapered surface which reduces in diameter towards the neck tip side (main shaft M2 side), and a cylindrical outer member 59 which forms an inner tapered surface that conforms to the outer tapered surface of the inner member 58 and which forms an outer peripheral surface with a smaller diameter than the inner surface of the motor drive shaft 51.

[0112] The outer member 59 is divided into a plurality of (three in the figure) divided bodies 59a at equal intervals in the circumferential direction. The single connector 55 holds the multiple segments 59a in a reduced diameter state in which they are brought radially inward by, for example, an endless elastic member 59b wound around an outer peripheral groove of the outer member 59 (see FIG. 42(a)).

[0113] The connector 55 is inserted into the motor drive shaft 51, and a connecting bolt 56 is attached to the main shaft M2 and tightened, compressing the expanding washer device 57 in the axial direction between the reduced diameter portion 52 of the drive shaft 51 and the head of the connecting bolt 56. As a result, the inner member 58 is pressed into the recess surrounded by the inner tapered surface of the outer member 59. Then, each divided body 59a of the outer member 59 moves radially outward along the outer tapered surface of the inner member 58 and the inner tapered surface of the outer member 59 against the biasing force of the elastic member 59b.

[0114] Each segment 59a moves radially outward evenly along the inner and outer tapered surfaces, and eventually reaches an expanded diameter state in which the outer circumferential surface of each segment 59a abuts the inner circumferential surface of the motor drive shaft 51 (see FIG. 42(b)). By further tightening the connecting bolt 56, the outer circumferential surface of each segment 59a presses against the inner circumferential surface of the motor drive shaft 51, thereby aligning the main shaft M2 and the motor drive shaft 51. In this way, the single action of tightening the connecting bolt 56 of the connector 55 can precisely connect the main shaft M2 and the motor drive shaft 51 coaxially.

[0115] That is, the drive device 10 having the above-mentioned configuration includes a housing 12, main shafts M1, M2 having a first central axis C1, and an eccentric shaft M3 having a second central axis C2 parallel to the first central axis C1 and positioned eccentrically with respect to the main shafts M1, M2. A first crankshaft CR1 is supported at both axial ends of the main shafts M1, M2 by the housing 12 so as to be rotatable about the first central axis C1. A second crankshaft CR2 is supported by the eccentric shaft M3 so as to be rotatable about the second central axis C2, and includes a first journal portion JA1 eccentric in one direction with respect to the second central axis C2 and a second journal portion JA2 eccentric in the other direction with respect to the second central axis C2. A first slider S1 is rotatably provided on the first journal portion JA1. A second slider S2 is rotatably provided on the second journal portion JA2. the housing 12 includes a first moving body (first piston P1, connecting rod CN1) rotatably connected to the first journal portion JA1 and linearly moving in a first direction (Y direction) perpendicular to the first central axis C1 in response to the movement of the first journal portion JA1; a second moving body (second piston P2 and connecting rod CN2) rotatably connected to the second journal portion JA2 and linearly moving in a second direction (Z direction) perpendicular to the first central axis C1 and perpendicular to the first direction in response to the movement of the second journal portion JA2; a first guide body 30 provided in the housing 12 and guiding the movement of the first slider S1 along the first direction; and a second guide body 32 provided in the housing 12 and guiding the movement of the second slider S2 along a second direction (Z direction) perpendicular to the first central axis C1 and perpendicular to the first direction. The main shafts M1, M2 are coaxially connected to a hollow drive shaft 51 arranged on the axial outside by being inserted into the drive shaft 51, and the main shafts M1, M2 and the drive shaft 51 are connected using a connecting device 55 inserted into the drive shaft 51 from the axial outside. The connecting device 55 is equipped with a connecting bolt 56 attached to a screw hole formed in the axial center portion of the main shaft M2, and an expanding washer device 57 which can abut against a reduced diameter portion 52 formed on the inner circumference of the drive shaft 51 from the axial outside, and which moves multiple movable bodies evenly radially outward by tightening the connecting bolt 56, thereby achieving an expanded diameter state.

[0116] According to this configuration, the main shaft M2 and the motor drive shaft 51 can be coaxially connected with high precision by a single operation of tightening the connecting bolt 56 of the connecting tool 55. This makes it possible to provide a drive device that meets the demand for easy manufacture and assembly even when a complex mechanism such as the two-axis oscillating linear drive mechanism 20 is employed.

[0117] Although some embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. The new embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. The embodiments and their modifications are included in the scope and spirit of the invention, and are included in the scope of the invention and its equivalents described in the claims. Among the embodiments disclosed in this specification, those that are composed of multiple objects may be integrated, and conversely, those that are composed of one object may be divided into multiple objects. Regardless of whether they are integrated or not, it is sufficient that they are configured to achieve the object of the invention. [Explanation of symbols]

[0118] 10 Drive unit 12. Chassis C1 1st center axis C2 2nd central axis M1, M2 main shaft M3 eccentric shaft CR1 First crankshaft JA1 1st Journal Section JA2 2nd Journal Section CR2 Second crankshaft S1 First slider GA1, GA2 Pair of guide surfaces S2 Second slider GB1, GB2 Pair of guide surfaces P1 First piston (first moving body) CN1 Connecting rod (first moving body) P2 Second piston (second moving body) CN2 Connecting rod (second moving body) 30 First guide body 30a Guide surface 32 Second guide body 32a Guide surface 14a: third guide body, first cylinder 14b Fourth guide body, second cylinder P1 First piston CN1 First connecting rod 22 Through hole W1 First counterweight IW1 First inner counterweight W2 Second counterweight IW2 No. 2 inner counterweight

Claims

1. A housing and a first crankshaft including a main shaft having a first central axis and an eccentric shaft having a second central axis parallel to the first central axis and positioned eccentrically with respect to the main shaft, both axial ends of the main shaft being supported by the housing so as to be rotatable around the first central axis; a second crankshaft supported by the eccentric shaft so as to be rotatable about the second central axis, the second crankshaft including a first journal portion eccentric in one direction with respect to the second central axis and a second journal portion eccentric in another direction with respect to the second central axis; a first slider rotatably provided on the first journal portion; a second slider rotatably provided on the second journal portion; a first movable body that is rotatably connected to the first journal portion and that linearly moves in a first direction perpendicular to the first central axis in accordance with the movement of the first journal portion; a first guide body provided in the housing and configured to guide the movement of the first slider along the first direction; a second guide body provided in the housing and configured to guide movement of the second slider along a second direction perpendicular to the first central axis and perpendicular to the first direction, At least one of the first guide body and the second guide body is configured separately from the housing and is removably fixed to the housing.

2. The guide body, which is separate from the housing, is fixed to the housing by fastening with a bolt, 2. The drive unit according to claim 1, wherein the bolt is disposed in a direction perpendicular to the first central axis and perpendicular to a moving direction of the slider guided by the separate guide body.

3. A housing and a first crankshaft including a main shaft having a first central axis and an eccentric shaft having a second central axis parallel to the first central axis and positioned eccentrically with respect to the main shaft, both axial ends of the main shaft being supported by the housing so as to be rotatable around the first central axis; a second crankshaft supported by the eccentric shaft so as to be rotatable about the second central axis, the second crankshaft including a first journal portion eccentric in one direction with respect to the second central axis and a second journal portion eccentric in another direction with respect to the second central axis; a first slider rotatably provided on the first journal portion; a second slider rotatably provided on the second journal portion; a first movable body that is rotatably connected to the first journal portion and that linearly moves in a first direction perpendicular to the first central axis in accordance with the movement of the first journal portion; a first guide body provided in the housing and configured to guide the movement of the first slider along the first direction; a second guide body provided in the housing and configured to guide movement of the second slider along a second direction perpendicular to the first central axis and perpendicular to the first direction, At least one of the first slider and the second slider includes a pair of side surface portions extending in a moving direction on both sides in a width direction perpendicular to the moving direction of the slider when viewed from an axial direction along the first central axis, The side surface portion includes an arc-shaped portion having a convex curvature outward in the width direction when viewed in an axial direction along the first central axis.

4. The drive device according to claim 3 , wherein the side surface portion has a straight portion along the movement direction in a middle range of the arcuate portion in the movement direction, when viewed from an axial direction along the first central axis.

5. A housing and a first crankshaft including a main shaft having a first central axis and an eccentric shaft having a second central axis parallel to the first central axis and positioned eccentrically with respect to the main shaft, both axial ends of the main shaft being supported by the housing so as to be rotatable around the first central axis; a second crankshaft supported by the eccentric shaft so as to be rotatable about the second central axis, the second crankshaft including a first journal portion eccentric in one direction with respect to the second central axis and a second journal portion eccentric in another direction with respect to the second central axis; a first slider rotatably provided on the first journal portion; a second slider rotatably provided on the second journal portion; a first movable body that is rotatably connected to the first journal portion and that linearly moves in a first direction perpendicular to the first central axis in accordance with the movement of the first journal portion; a first guide body provided in the housing and configured to guide the movement of the first slider along the first direction; a second guide body provided in the housing and configured to guide movement of the second slider along a second direction perpendicular to the first central axis and perpendicular to the first direction, A drive device in which the first journal portion and the second journal portion are formed separately from each other and are integrally connected in the axial direction to form the second crankshaft.

6. the second crankshaft has a through hole extending through the first journal portion and the second journal portion, The eccentric shaft is inserted into the through hole, 6. The drive device according to claim 5, wherein a tapered surface inclined in the axial direction and in the radial direction is formed on a peripheral edge of an opening of the through hole and on an annular corner formed on an outer periphery of the eccentric shaft.

7. the first crankshaft includes a first counterweight disposed at one end of the eccentric shaft and a second counterweight disposed at the other end of the eccentric shaft, 7. The drive device according to claim 5, wherein at least one of the first counterweight and the second counterweight is configured separately from the eccentric shaft.

8. A housing and a first crankshaft including a main shaft having a first central axis and an eccentric shaft having a second central axis parallel to the first central axis and positioned eccentrically with respect to the main shaft, both axial ends of the main shaft being supported by the housing so as to be rotatable around the first central axis; a second crankshaft supported by the eccentric shaft so as to be rotatable about the second central axis, the second crankshaft including a first journal portion eccentric in one direction with respect to the second central axis and a second journal portion eccentric in another direction with respect to the second central axis; a first slider rotatably provided on the first journal portion; a second slider rotatably provided on the second journal portion; a first movable body that is rotatably connected to the first journal portion and that linearly moves in a first direction perpendicular to the first central axis in accordance with the movement of the first journal portion; a first guide body provided in the housing and configured to guide the movement of the first slider along the first direction; a second guide body provided in the housing and configured to guide movement of the second slider along a second direction perpendicular to the first central axis and perpendicular to the first direction, A separate counterweight is detachably attached to at least one of the first journal portion and the second journal portion, The separate counterweight has an arc portion that is tangent to the outer peripheral surface of the journal portion to which it is attached in the circumferential direction, in the range where the eccentric weight is provided, and a drive device in which an open portion is formed by cutting out in the circumferential direction in the range where the eccentric weight is not provided.

9. A journal portion to which the separate counterweight is attached is formed with a recess that is recessed toward the inner periphery with respect to the outer periphery, The separate counterweight has a protrusion that is inserted into the recess, 9. The drive device according to claim 8, wherein at least one of the recessed portion and the protruding portion has a surface that intersects with the circumferential direction of the outer circumferential surface as a surface that can abut against the other of the recessed portion and the protruding portion in the circumferential direction of the outer circumferential surface.

10. A housing and a first crankshaft including a main shaft having a first central axis and an eccentric shaft having a second central axis parallel to the first central axis and positioned eccentrically with respect to the main shaft, both axial ends of the main shaft being supported by the housing so as to be rotatable around the first central axis; a second crankshaft supported by the eccentric shaft so as to be rotatable about the second central axis, the second crankshaft including a first journal portion eccentric in one direction with respect to the second central axis and a second journal portion eccentric in another direction with respect to the second central axis; a first slider rotatably provided on the first journal portion; a second slider rotatably provided on the second journal portion; a first movable body that is rotatably connected to the first journal portion and that linearly moves in a first direction perpendicular to the first central axis in accordance with the movement of the first journal portion; a first guide body provided in the housing and configured to guide the movement of the first slider along the first direction; a second guide body provided in the housing and configured to guide movement of the second slider along a second direction perpendicular to the first central axis and perpendicular to the first direction, the eccentric shaft is a hollow shaft, and an internal space of the eccentric shaft is an internal oil passage for supplying lubricating oil to the second crankshaft and a movable part supported by the second crankshaft, The eccentric shaft has an oil hole formed therein, the oil hole extending radially outward from the oil passage in the shaft and opening at an outer periphery of the eccentric shaft.

11. A housing and a first crankshaft including a main shaft having a first central axis and an eccentric shaft having a second central axis parallel to the first central axis and positioned eccentrically with respect to the main shaft, both axial ends of the main shaft being supported by the housing so as to be rotatable around the first central axis; a second crankshaft supported by the eccentric shaft so as to be rotatable about the second central axis, the second crankshaft including a first journal portion eccentric in one direction with respect to the second central axis and a second journal portion eccentric in another direction with respect to the second central axis; a first slider rotatably provided on the first journal portion; a second slider rotatably provided on the second journal portion; a first movable body that is rotatably connected to the first journal portion and that linearly moves in a first direction perpendicular to the first central axis in accordance with the movement of the first journal portion; a first guide body provided in the housing and configured to guide the movement of the first slider along the first direction; a second guide body provided in the housing and configured to guide movement of the second slider along a second direction perpendicular to the first central axis and perpendicular to the first direction; a third guide body provided in the housing and configured to guide the linear motion of the first moving body; the third guide body has a first cylinder provided in the housing and extending in the first direction, the first movable body has a first piston inserted into a cylinder liner of the first cylinder so as to be reciprocable in the first direction; A drive device in which a tapered inner circumferential surface that increases in diameter toward the end is formed at the base end of the cylinder liner on the housing side, and an arc-shaped notch is formed when viewed in the axial direction of the second crankshaft.

12. A housing and a first crankshaft including a main shaft having a first central axis and an eccentric shaft having a second central axis parallel to the first central axis and positioned eccentrically with respect to the main shaft, both axial ends of the main shaft being supported by the housing so as to be rotatable around the first central axis; a second crankshaft supported by the eccentric shaft so as to be rotatable about the second central axis, the second crankshaft including a first journal portion eccentric in one direction with respect to the second central axis and a second journal portion eccentric in another direction with respect to the second central axis; a first slider rotatably provided on the first journal portion; a second slider rotatably provided on the second journal portion; a first movable body that is rotatably connected to the first journal portion and that linearly moves in a first direction perpendicular to the first central axis in accordance with the movement of the first journal portion; a second movable body that is rotatably connected to the second journal portion and that linearly moves in a second direction perpendicular to the first central axis and perpendicular to the first direction in response to movement of the second journal portion; a first guide body provided in the housing and configured to guide the movement of the first slider along the first direction; a second guide body provided in the housing and configured to guide movement of the second slider along a second direction perpendicular to the first central axis and perpendicular to the first direction, the first movable body includes a first piston reciprocatable in the first direction, and a first connecting rod having one end connected to the first piston and the other end connected to the first journal portion so as to be rotatable therewith, the second movable body includes a second piston reciprocatable in the second direction, and a second connecting rod having one end connected to the second piston and the other end connected to the second journal portion so as to be rotatable therewith, A drive device, wherein the first connecting rod and the second connecting rod have different hollowed-out portions.

13. A housing and a first crankshaft including a main shaft having a first central axis and an eccentric shaft having a second central axis parallel to the first central axis and positioned eccentrically with respect to the main shaft, both axial ends of the main shaft being supported by the housing so as to be rotatable around the first central axis; a second crankshaft supported by the eccentric shaft so as to be rotatable about the second central axis, the second crankshaft including a first journal portion eccentric in one direction with respect to the second central axis and a second journal portion eccentric in another direction with respect to the second central axis; a first slider rotatably provided on the first journal portion; a second slider rotatably provided on the second journal portion; a first movable body that is rotatably connected to the first journal portion and that linearly moves in a first direction perpendicular to the first central axis in accordance with the movement of the first journal portion; a first guide body provided in the housing and configured to guide the movement of the first slider along the first direction; a second guide body provided in the housing and configured to guide movement of the second slider along a second direction perpendicular to the first central axis and perpendicular to the first direction; a third guide body provided in the housing and configured to guide the linear motion of the first moving body; The main shaft is coaxially connected to a hollow outer shaft disposed axially outwardly of the main shaft in a state where the outer shaft is inserted into the hollow outer shaft, The main shaft and the outer shaft are connected to each other using a connecting tool inserted into the outer shaft from the axially outer side, The connecting device is a drive device comprising: a connecting bolt that is attached to a screw hole formed in the axial center portion of the main shaft; and an expanding washer device that can abut from the outside in the axial direction on a reduced diameter portion formed on the inner circumference of the outer shaft, and that moves multiple movable bodies evenly radially outward to an expanded diameter state by tightening the connecting bolt.

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