JP2006161786A - Starter of internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a starter of an internal combustion engine with reduced clacking sound. <P>SOLUTION: This starter 1 of the internal combustion engine is provided with a ring gear 10 and a pinion gear 20 as a start gear meshing with the ring gear 10 and driving the ring gear 10. The ring gear 10 has a top dead center position 13 corresponding to the top dead center and a bottom dead center position 14 corresponding to the bottom dead center. The ring gear 10 includes a first region 11 at the top dead center position 13 and a second region 12 corresponding to an expansion process of the internal combustion engine between the top dead center position 13 and the bottom dead center 14. Backlash between the ring gear 10 and the pinion gear 20 in the second region 12 is smaller than backlash between the ring gear 10 and the pinion gear 20 in the first region 11. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an internal combustion engine starter, and more particularly to an internal combustion engine starter that can reduce the occurrence of rattling noise.

Conventional internal combustion engine starters include, for example, Japanese Utility Model Laid-Open No. 4-24668 (Patent Document 1), Japanese Patent Application Laid-Open No. 2002-130098 (Patent Document 2), Japanese Patent Application Laid-Open No. 64-15461 (Patent Document 3), This is disclosed in Japanese Patent Application Laid-Open No. 64-15463 (Patent Document 4).
Japanese Utility Model Publication No. 4-24668 JP 2002-130098 A Japanese Unexamined Patent Publication No. 64-15461 JP-A 64-15463

  Patent Document 1 discloses an engine starter that varies the meshing between a ring gear and a starter pinion gear.

  Patent Document 2 discloses an engine starting device in which the engagement between a ring gear and a starter pinion gear is different.

  Patent Documents 3 and 4 disclose a configuration in which the starter slides and meshes in the radial direction of the gear.

  However, in any of the conventional techniques, there is a problem that it is not possible to reduce the rattling noise in the expansion stroke of the internal combustion engine.

  Accordingly, the present invention has been made to solve the above-described problems, and an object thereof is to provide a starter for an internal combustion engine that can reduce rattling noise in an expansion stroke.

  An internal combustion engine starter according to the present invention includes a ring gear that rotates together with a crankshaft of an internal combustion engine having a piston, and a start gear that engages the ring gear and drives the ring gear when the internal combustion engine is started. The ring gear has a top dead center position corresponding to the top dead center of the piston and a bottom dead center position corresponding to the bottom dead center of the piston. The ring gear includes a first region at the top dead center position, A second region corresponding to the expansion stroke of the internal combustion engine between the dead center position and the bottom dead center position, and the backlash between the ring gear and the start gear in the second region is Smaller than the backlash between the start gear.

  In the internal combustion engine starter configured as described above, the backlash between the ring gear and the start gear in the second region corresponding to the expansion stroke is more than the backlash between the ring gear and the start gear in the first region. Since it is small, the gap between the ring gear and the start gear is reduced during the expansion stroke. As a result, rattling noise between the start gear and the ring gear can be prevented even when the ring gear is driven by the piston during the expansion stroke. As a result, it is possible to reduce the internal combustion engine starter device in which the rattling noise in the expansion stroke is reduced.

  More preferably, the start gear is slidable in the radial direction of the ring gear, and is slid in the radial direction so as to approach the ring gear when the internal combustion engine is started, and meshes with the ring gear.

  Preferably, a control device is further provided for controlling the phase of the ring gear so that the start gear meshes with the first region when the internal combustion engine is started.

  An internal combustion engine starter according to the present invention includes a ring gear that rotates together with a crankshaft of the internal combustion engine, and a start gear that engages the ring gear and drives the ring gear when the internal combustion engine is started. The ring gear has a portion that meshes with the start gear during the expansion stroke of the internal combustion engine, and backlash between the ring gear and the start gear in that portion is between the ring gear and the start gear in other portions. Smaller than backlash.

  In the internal combustion engine starter configured as described above, since the backlash of the ring gear portion that meshes with the pinion gear is small during the expansion stroke, it is possible to reduce the occurrence of rattling noise during the expansion stroke.

  According to the present invention, it is possible to provide an internal combustion engine starter that can reduce the occurrence of rattling noise.

  Embodiments of the present invention will be described below with reference to the drawings. In the following embodiments, the same or corresponding parts are denoted by the same reference numerals, and description thereof will not be repeated.

(Embodiment 1)
FIG. 1 is a schematic diagram of an internal combustion engine starter according to Embodiment 1 of the present invention. Referring to FIG. 1, a starter 1 for an internal combustion engine according to Embodiment 1 of the present invention includes a ring gear 10 connected to a piston 34 and rotating together with a crankshaft 31, and a ring gear 10 at the start of the internal combustion engine. And a pinion gear 20 as a start gear for driving the meshing ring gear 10. The ring gear 10 has a top dead center position 13 corresponding to the top dead center of the piston 34 and a bottom dead center position 14 corresponding to the bottom dead center of the piston 34. The ring gear 10 includes a first region 11 at a top dead center position 13 and a second region 12 corresponding to the expansion stroke of the internal combustion engine between the top dead center position 13 and the bottom dead center position 14.

  The backlash between the ring gear 10 and the pinion gear 20 in the second region 12 is smaller than the backlash between the ring gear 10 and the pinion gear 20 in the first region 11. When starting the internal combustion engine, an ECU (electronic control unit) 50 as a control device adjusts the phase of the ring gear 10 so that the pinion gear 20 meshes with a portion (first region 11) of the ring gear 10 different from the second region 12. Control.

  An internal combustion engine starter 1 includes a ring gear 10 that is connected to a crankshaft 31 of an internal combustion engine and rotates together with a piston, and a pinion as a start gear that engages the ring gear 10 and drives the ring gear 10 when the internal combustion engine is started. And a gear 20. The ring gear 10 has a second region 12 that meshes with the pinion gear 20 during the expansion stroke of the internal combustion engine, and the backlash between the ring gear 10 and the pinion gear 20 at that portion is the ring gear at the other portion. And smaller than the backlash between the start gear.

  The ring gear 10 is connected to the crankshaft 31 and rotates together with the crankshaft 31. The crankshaft 31 is an output shaft of the internal combustion engine, and a crank arm 32 is provided on the crankshaft 31 so as to extend in the radial direction (radial direction) of the ring gear 10. The crank arm 32 is connected to a connecting rod 33, and a piston 34 is attached to the tip of the connecting rod 33. The piston 34 reciprocates in a space surrounded by the cylinder wall 35, and receives a force so that the piston 34 is pressed downward by the combustion of fuel. This force is converted into a rotational force by the connecting rod 33 and the crank arm 32, and the crankshaft 31 rotates.

  FIG. 1 shows a state in which the piston 34 is at the top dead center, which is the end of the compression stroke or the end of the exhaust stroke. A top dead center position 13 and a bottom dead center position 14 of the ring gear 10 are located on an extension line of the crank arm 32. The ring gear 10 includes a first region 11 having a low meshing rate with the pinion gear (large backlash) and a second region 12 having a high meshing rate with the pinion gear 20 (low backlash). The ring gear 10 is annular, and a tooth surface is formed on the outer peripheral portion thereof. This tooth may be either a spur gear or a spiral gear. In FIG. 1, the ring gear 10 rotates clockwise. The rotation of the ring gear 10 is synchronized with the rotation of the crankshaft 31.

  The pinion gear 20 is connected to a cell motor (not shown), and the pinion gear 20 is rotated by the cell motor. The pinion gear 20 meshes with the ring gear 10 only when the internal combustion engine is started, and rotates the ring gear 10. As a result, cranking occurs and the engine starts. The position of the pinion gear 20 is the first region 11 having a low meshing rate, that is, a large backlash. This is because the pinion gear 20 meshes with the ring gear 10 only at the start, and in other cases the pinion gear 20 is located away from the ring gear 10, so that the pinion gear 20 can be easily meshed with the ring gear 10. .

  A top dead center position 13 and a bottom dead center position 14 are provided at the facing portions of the ring gear 10. Both the top dead center position 13 and the bottom dead center position 14 are regions that are 180 ° out of phase. The top dead center position 13 is the position where the compression stroke is completed and the position where the exhaust stroke is completed, and the bottom dead center position 14 is the position where the suction stroke is completed and the position where the expansion stroke is completed.

  In FIG. 1, the 2nd area | region 12 with a high meshing rate of the ring gear 10 is provided facing. This indicates that the internal combustion engine shown in FIG. 1 is an in-line four-cylinder engine. In an in-line 4-cylinder engine, the top dead center and bottom dead center positions of the two pistons at both ends are the same, and the top dead center position and bottom dead center position of the two central pistons are generally the same. . In FIG. 1, the piston 34 located at the end of the four cylinders is shown, and the piston located in the center rotates at a phase shifted by 180 ° from the piston 34 shown in FIG. That is, when the pistons 34 at both ends are located at the top dead center, the center piston is located at the bottom dead center, and when the pistons 34 at both ends are located at the bottom dead center, the center piston is located at the top dead center. To do. A region corresponding to the compression stroke of each piston is a second region 12.

  In this example, an in-line four-cylinder engine is shown, but the present invention can be applied to an engine having a single cylinder or a plurality of cylinders.

  Further, regarding the arrangement of the pistons, the present invention can be applied not only to the series type but also to various engines such as a V type, a W type, and a horizontally opposed type.

  2 and 3 are diagrams for explaining the pinion gear meshing with the second region. Referring to FIG. 2, second region 12 and pinion gear 20 mesh with each other at the initial stage of the expansion stroke. In the expansion stroke (explosion stroke), the piston 34 is pushed downward, and the rotation of the ring gear 10 is accelerated by the piston 34. Therefore, the tooth surface of the ring gear 10 presses the tooth surface of the pinion gear 20. However, since the clearance (backlash) between the tooth surfaces between the second region 12 and the pinion gear 20 is small, it is possible to reduce the rattling noise.

  Referring to FIG. 3, second region 12 meshes with pinion gear 20 until the end of the expansion stroke. Since the second region 12 has a high meshing rate with respect to the pinion gear 20 (backlash is small), even if the ring gear 10 rotates so as to accelerate, the rattling noise can be reduced.

  That is, in the case of an in-line four-cylinder engine, since one of the four cylinders is in the compression stroke near the top dead center and the bottom dead center, the compression torque of the engine increases and the engine speed is descend.

  On the other hand, between the top dead center position and the bottom dead center, since any one of the four cylinders is in the expansion (explosion) stroke, the engine speed increases. When the engine speed increases, the rotation speed of the ring gear 10 also increases, and the rotation of the ring gear 10 becomes faster than the pinion gear 20 of the starter. At this time, if the gap between the gears is large, a force is applied in the direction in which the ring gear 10 pushes the pinion gear 20, so that the gear and the gear are momentarily separated and contacted in the opposite direction. Further, when the expansion stroke is passed and the engine approaches the top dead center or the bottom dead center, the engine speed decreases, so that the pinion gear 20 pushes the ring gear 10 and the gear and the gear are separated for a moment. By repeating these, a rattling sound is generated. In the present invention, it is possible to prevent the gear teeth from separating by increasing the meshing ratio of the gear teeth between the top dead center position 13 and the bottom dead center position 14. As a result, generation of rattling noise can be prevented.

  Further, the meshing position of the pinion gear 20 is mounted so as to be in the first region 11 where the meshing rate is low when the engine is stopped. As such control, the stop position of the ring gear 10 is adjusted using the ECU 50. Thereby, the engagement of the pinion gear 20 and the ring gear 10 can be facilitated during driving.

(Embodiment 2)
FIG. 4 is a schematic diagram of an internal combustion engine starter according to Embodiment 2 of the present invention. Referring to FIG. 4, in the starting device according to the second embodiment of the present invention, idle gear 21 meshes with pinion gear 20, and this idle gear slides in the direction indicated by arrow 23 to mesh with ring gear 10. Fit. That is, the idle gear 21 as the start gear can slide in the radial direction of the ring gear 10 (direction indicated by the arrow 23), and slides in the radial direction in the direction approaching the ring gear 10 when the internal combustion engine is started. To bite.

  When the starter is not driven, the idle gear 21 is stopped at a distance from the ring gear 10. When the starter is driven, the idle gear 21 slides toward the ring gear 10 and meshes with the ring gear 10 to transmit the drive torque of the starter to the engine side.

  In the internal combustion engine starter 1 according to the second embodiment as described above, since the idle gear 21 slides in the radial direction, it is necessary to reduce the gear meshing rate as in a conventional axial slide type starter. Since there is no noise, the rattling noise can be reduced.

  Although the embodiment of the present invention has been described above, the embodiment shown here can be variously modified.

  First, the engine to which the present invention is applied is not limited to a reciprocating engine, but may be a rotary engine. That is, the same effect can be obtained by reducing the backlash of the ring gear portion that meshes with the start gear in the expansion stroke of the rotary engine.

  Furthermore, the present invention can be applied to either a diesel engine or a gasoline engine as a reciprocating engine.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  The present invention can be used in the field of internal combustion engines.

1 is a schematic diagram of a starting device for an internal combustion engine according to Embodiment 1 of the present invention. FIG. It is a figure for demonstrating the pinion gear which meshes with a 2nd area | region. It is a figure for demonstrating the pinion gear which meshes with a 2nd area | region. It is a schematic diagram of a starting device for an internal combustion engine according to a second embodiment of the present invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Start device of internal combustion engine, 10 Ring gear, 11 1st area | region, 12 2nd area | region, 20 Pinion gear, 21 Idle gear, 31 Crankshaft, 32 Crank arm, 33 Connecting rod, 34 Piston, 35 Cylinder wall, 50 ECU .

Claims (4)

A ring gear that rotates with a crankshaft of an internal combustion engine having a piston;
A start gear that meshes with the ring gear when the internal combustion engine is started and drives the ring gear;
The ring gear has a top dead center position corresponding to the top dead center of the piston and a bottom dead center position corresponding to the bottom dead center of the piston,
The ring gear includes a first region at the top dead center position, a second region corresponding to an expansion stroke of the internal combustion engine between the top dead center position and the bottom dead center position, The internal combustion engine starter, wherein a backlash between the ring gear and the start gear is smaller than a backlash between the ring gear and the start gear in the first region.   2. The internal combustion engine according to claim 1, wherein the start gear is slidable in a radial direction of the ring gear, and is slid in a radial direction so as to approach the ring gear when the internal combustion engine is started to mesh with the ring gear. Starter.   The starter for an internal combustion engine according to claim 2, further comprising a control device that controls a phase of the ring gear so that the start gear meshes with the first region when the internal combustion engine is started. A ring gear that rotates with the crankshaft of the internal combustion engine;
A start gear that meshes with the ring gear when the internal combustion engine is started and drives the ring gear;
The ring gear has a portion that meshes with the start gear during an expansion stroke of the internal combustion engine, and backlash between the ring gear and the start gear in that portion is between the ring gear and the start gear in other portions. An internal combustion engine starter that is smaller than the backlash in between.

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