JP2006063836A - Rotation detection rotor and crankshaft - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide technologies for taking advantage of space and performing adjustment of balance of the crankshaft more easily at the time of attachment of a rotor for rotation detection to the crankshaft. <P>SOLUTION: A sensing rotor 6 of the crankshaft 1 is provided with a part 7 to be detected of which the rotation is detected by a sensor 106. Then a rotor body is provided with a weight mass 10 for adjusting the balance of the crankshaft 1. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a rotation detection rotor and a crankshaft.

  In an internal combustion engine, control relating to engine operating conditions such as ignition timing and fuel injection amount is performed by detecting the position of the crankshaft.

In order to detect the position of the crankshaft, for example, a sensor is provided in the cylinder block, and a sensing rotor corresponding to the sensor is attached to the counterweight of the crankshaft (see, for example, Patent Document 1).
Japanese Patent Laid-Open No. 10-331681 JP-A-8-144781 JP-A-6-288329 JP-A-8-109949 Japanese Utility Model Publication No. 5-90002

  By the way, in the sensing rotor mounting structure disclosed in Patent Document 1, a space for the counterweight of the crankshaft is secured by forming the sensing rotor with a thin sheet metal member.

  In such a case, the mounting screw is attached to the side of the counterweight via the sensing rotor, so that there is a space (gap, space) for the head of the mounting screw between the sensing rotor and the cylinder block or lower crankcase. It is necessary to secure.

  In the space provided for the head of the mounting screw, only the head of the mounting screw is located, and the space other than the portion used for the head of the mounting screw has not been effectively used.

  The present invention has been made in view of the circumstances as described above, and when attaching a rotation detection rotor to a crankshaft, it is possible to effectively adjust the balance of the crankshaft by effectively using space. The purpose is to provide.

In order to achieve the above object, in the present invention,
In the rotor for detecting rotation of the crankshaft provided with the detected portion whose rotation is detected by the rotation detecting means,
The rotor main body is provided with a weight (mass, weight) for adjusting the balance of the crankshaft.

As described above, when the rotation detection rotor is attached to the crankshaft, the rotation detection rotor can be applied as a part of the counterweight of the crankshaft by providing a weight in the rotor body. Therefore, the balance of the crankshaft can be adjusted more easily by adjusting the weight of the rotor body. In addition, if a rotation detection rotor with a weight is attached to a part of the counterweight that has been cut away, the space can be used effectively, and the length of the counterweight in the axial direction of the crankshaft In addition to this, it is not necessary to ensure the length of the rotation detection rotor, and it is possible to prevent the crankshaft from becoming longer in the axial direction.

In the above configuration, the rotation detection rotor is configured by a thin plate-like member, and the attachment member is attached to the rotor attachment portion via the rotation detection rotor, on the rotor attachment portion provided on the counterweight side portion of the crankshaft. It is fixed by being locked,
The weight may be provided up to the vicinity of the end of the attachment member in the axial direction when the rotation detection rotor is attached to the rotor attachment portion by the attachment member.

  In the rotation detection rotor, the mounting member is usually moved in the axial direction of the crankshaft through a hole provided on a side surface of the rotor body (an end surface in the axial direction of the crankshaft, a surface substantially orthogonal to the axial direction of the crankshaft). By being locked to the mounting portion, it is fixed to the rotor mounting portion. When the crankshaft is applied to an internal combustion engine (when installed in a cylinder block or a lower crankcase), the mounting member (particularly the head portion of the mounting member) protrudes in the axial direction. A wasted space is generated between the lower crankcase and the rotor body. By providing the weight on the rotation detection rotor so that the weight is positioned in this space, it is possible to effectively use the useless space generated by the attachment member. Thereby, balance adjustment of a crankshaft can be performed more easily and it can suppress that the length of the axial direction of a crankshaft becomes long.

Further, in the rotor for detecting the rotation of the crankshaft constituted by a thin plate-like member having a detected portion whose rotation is detected by the rotation detecting means, and attached to the counterweight of the crankshaft
An attachment portion is provided on a part of the rotor main body and is attached and fixed to the outer peripheral surface of the counterweight by an attachment member when attached to the counterweight of the crankshaft.

  As described above, the rotation detecting rotor is mounted and fixed to the outer peripheral surface of the counterweight by the mounting member, so that the mounting direction of the mounting member can be angled with respect to the axial direction of the crankshaft. It can suppress that an attachment member protrudes in the axial direction of a shaft. As a result, when the crankshaft is applied to an internal combustion engine, it is possible to prevent a useless space from being generated between the cylinder block or the lower crankcase and the rotor body. It becomes possible to further suppress the portion of the crankshaft where the counterweight is shaved. Accordingly, the balance of the crankshaft can be more easily adjusted by effectively using the space, and the length of the crankshaft in the axial direction can be suppressed from becoming longer.

  The mounting portion may be provided in a portion where a part of the thin plate member constituting the rotor body is bent (a portion having an angle with respect to a direction orthogonal to the axial direction of the crankshaft).

In the above configuration, the crankshaft is provided with a plurality of counterweights in the axial direction.
The rotation detecting rotor may be attached to a counterweight provided in a central region among the plurality of counterweights.

In adjusting the balance of the crankshaft, the counterweight on the outer side (end portion) is more important than the counterweight on the inner side (center region) of the crankshaft. This is because the center of gravity of the internal combustion engine to which the crankshaft is applied is substantially in the middle of the crankshaft, and the moment becomes larger when a weight is placed at a position that is longer than the center of gravity.

  Therefore, the counterweight in the central area has less influence on the balance of the crankshaft than the counterweight on the outside, so it is better to adjust the balance of the crankshaft by attaching the rotation detection rotor to the counterweight in the central area. It can be done easily.

  The crankshaft according to the present invention is characterized in that the rotation detection rotor described above is attached and fixed to a counterweight.

  In addition, said each structure can be employ | adopted combining as much as possible.

  ADVANTAGE OF THE INVENTION According to this invention, when attaching a rotor for rotation detection to a crankshaft, it becomes possible to provide the technique which can utilize a space effectively and can perform balance adjustment of a crankshaft more easily.

  The best mode for carrying out the present invention will be exemplarily described in detail below on the basis of embodiments with reference to the drawings.

  FIG. 1 is a schematic cross-sectional view showing a main part of an internal combustion engine 100 to which a crankshaft 1 according to a first embodiment of the present invention is applied, and shows a cross section orthogonal to the axial direction of the crankshaft 1. FIG. 2 is a schematic perspective view showing a state where the piston 104 is attached to the crankshaft 1 according to the first embodiment of the present invention. FIG. 3 is a schematic view showing the AA cross section shown in FIG. FIG. 4 is a schematic perspective view of a main part of the crankshaft 1 shown in FIG.

  First, the internal combustion engine 100 will be described.

  The internal combustion engine 100 supports a crankshaft 1 as an engine output shaft so as to be rotatable between a cylinder block (engine block) 101 and a lower crankcase 102. A piston 104 is connected to the crankshaft 1 via a connecting rod 103. The connecting rod 103 converts the reciprocating movement of the piston 104 into the rotation of the crankshaft 1. The piston 104 is provided so as to reciprocate within a cylinder 105 formed in the cylinder block 101.

  In the internal combustion engine 100, a combustion chamber is provided above the piston 104, and the combustion chamber is filled with a mixture of air and fuel. When the air-fuel mixture burns in the combustion chamber, the combustion force generated in the combustion chamber is converted into the rotational force of the crankshaft 1 through the piston 104 and the connecting rod 103.

  Next, the crankshaft 1 according to the present embodiment will be described.

  The crankshaft 1 includes a crankpin 2, a crank journal 3, a crank arm 4, a counterweight 5, and a sensing rotor 6.

The crankpin 2 is disposed at a position corresponding to the center of the cylinder 105, and is connected to the connecting rod 103, and an external force (combustion force) received by the piston 104 is loaded through the connecting rod 103.

  The crank journal 3 is a main shaft serving as a rotation center of the crankshaft 1 and is provided so as to be alternately arranged with the crankpin 2. Also, the crankshaft 1 is provided in the internal combustion engine 100 by the crank journal 3 being rotatably supported between the cylinder block 101 and the lower crankcase 102 via a bearing.

  The crank arm 4 is provided at both ends of the crankpin 2 and connects the crankpin 2 and the crank journal 3.

  The counterweight 5 appropriately maintains a rotation balance so that a large inertia force does not work when the piston 104, the connecting rod 103, and the crankshaft 1 rotate together, and in this embodiment, the crankshaft 1 Eight counterweights 51 to 58 are provided. Further, at least one counterweight of the plurality of counterweights 51 to 58 is provided with an attachment portion 5a for attaching the sensing rotor 6.

  The sensing rotor 6 is composed of a thin plate-like annular member, and is provided in an inner periphery of the sensing rotor 6 and attached to the attachment portion 5a of the counterweight 5 (attached), and disposed in the cylinder block 101. A detected portion 7 whose rotation is detected by a sensor 106 provided, and a weight mass 10 as a weight are provided.

  The to-be-detected part 7 is comprised by the protrusion 8 provided in every predetermined angle in at least one part of the outer periphery of a rotor main body. The sensing rotor 6 is attached to the attachment portion 5 a of the counterweight 5 and the crank arm 4 with attachment screws 9. Here, the sensing rotor 6 constitutes a rotation detecting rotor according to the present embodiment.

  The weight mass 10 is a characteristic configuration of the present embodiment, and is provided on the side surface 6b of the sensing rotor 6. When the sensing rotor 6 is attached to the counterweight 5 by the attachment screw 9, the attachment screw 9 It is provided to the vicinity of the tip of the screw head 9a.

  When the sensing rotor 6 is attached to the crankshaft 1, the attachment screw 9 is attached to the side surface 6b of the sensing rotor 6 from the axial direction of the crankshaft 1, so that the screw head 9a of the attachment screw 9 protrudes. When the screw head 9a protrudes in this way, useless space is generated between the side surface 6b of the sensing rotor 6 and the wall surface 101a of the cylinder block 101 (and / or the wall surface of the lower crankcase).

  In this embodiment, since the weight mass 10 is provided in this space, the wasted space can be used effectively. That is, when a space for mounting the sensing rotor 6 (mounting portion 5a) is provided by cutting a part of the counterweight 5, the counterweight function can be provided in that space. Therefore, it is not necessary to separately attach a weight, the balance of the crankshaft 1 can be adjusted more easily, and the axial length of the crankshaft 1 can be prevented from becoming longer.

Here, the weight mass 10 may be provided as long as it does not contact the wall surface 101a of the cylinder block 101 (and / or the wall surface of the lower crankcase). For example, in the crankshaft 1 before being assembled to the internal combustion engine 100, if the weight mass 10 is provided in a range that does not protrude in the axial direction of the crankshaft 1 from the screw head 9a of the mounting screw 9, the crankshaft is concerned. Even when 1 is assembled to the internal combustion engine 100, it does not come into contact with the wall surface 101a of the cylinder block 101 (and / or the wall surface of the lower crankcase).

  The sensing rotor 6 may be attached so that the weight mass 10 overlaps the counterweight 5 when projected in the axial direction of the crankshaft 1. As a result, the mounting portion 5a can also have a counterweight function.

  The sensing rotor 6 is a counterweight provided in the central region of the crankshaft 1, that is, a counterweight other than the end portions (counterweights 51 and 58) among the plurality of counterweights (any of the counterweights 52 to 57). ) Is preferably attached. Since the counterweight in the central region has less influence on the balance of the crankshaft 1 than the counterweight at the end, it is easier to adjust the balance of the crankshaft 1 by attaching the sensing rotor 6 to the counterweight in the central region. Can be done.

  Here, the case where the sensing rotor 6 is attached to the counterweight 5 provided in the central region will be described.

  When the sensing rotor 6 is attached to the counterweight 5 provided in the central region, for example, the sensing rotor 6 is attached in a state where a part of the inner peripheral surface of the attachment hole 6a of the sensing rotor 6 is positioned in the vicinity of the crank journal 3. The sensing rotor 6 can be moved to the central region of the crankshaft 1 by moving the part facing the part on the inner peripheral surface of the hole 6a and passing the counterweight 5 therethrough. In addition, the attachment hole 6a of the sensing rotor 6 is provided in a size capable of moving to the central region of the crankshaft 1 as described above.

  FIG. 5 is a schematic cross-sectional view showing a main part of the internal combustion engine 100 to which the crankshaft 1 according to the second embodiment of the present invention is applied, and shows a cross section orthogonal to the axial direction of the crankshaft 1. FIG. 6 is a schematic view of a main part of the crankshaft 1 shown in FIG. FIG. 7 is a schematic perspective view of the crankshaft 1 shown in FIG. The basic configuration of the internal combustion engine is the same as the configuration described in the first embodiment, and the same components are denoted by the same reference numerals and the description thereof is omitted.

  As a characteristic configuration of the present embodiment, the sensing rotor 60 according to the present embodiment is configured by a thin plate-shaped annular member, and is attached to the mounting portion 5a of the counterweight 5 provided on the inner periphery (fitting). The mounting hole 6a, the detected portion 7 whose rotation is detected by the sensor 106 disposed in the cylinder block 101, and the outer peripheral surface of the counterweight 5 by the mounting screw 9 when mounted on the counterweight 5. An attachment portion 61 that is attached and fixed to 5b is provided. The attachment portion 61 is provided in a portion where a part of the thin plate-like rotor body is bent.

  With this configuration, when the sensing rotor 60 is attached to the counterweight 5, the attachment direction by the attachment screw 9 has an angle with respect to the axial direction of the crankshaft 1 (in this embodiment, about 90 degrees). Become. As a result, the screw head 9a of the mounting screw 9 does not protrude as in the case where the mounting screw 9 is mounted on the side surface 6b of the sensing rotor 6 from the axial direction of the crankshaft 1 in the first embodiment. .

Further, the sensing rotor 60 is as far as possible on the wall surface 101a of the cylinder block 101 (and / or the wall surface of the lower crankcase) as long as it does not contact the wall surface 101a of the cylinder block 101 (and / or the wall surface of the lower crankcase). ) Side. As a result, when a part of the counterweight 5 is cut to provide a mounting space (attachment part 5a) for the sensing rotor 60, the attachment part 5a can be provided without cutting the counterweight 5 so much. Space can be secured.

  Therefore, there is no useless space between the side surface 62 of the sensing rotor 60 and the wall surface 101a of the cylinder block 101 (and / or the wall surface of the lower crankcase) due to the protrusion of the screw head 9a. It can be used efficiently. That is, since a useless space is generated, the weight is not further attached, so that the balance of the crankshaft 1 can be adjusted more easily, and the axial length of the crankshaft 1 becomes longer. This can be suppressed.

  Similarly to the first embodiment, the sensing rotor 60 has a counterweight provided in the central region of the crankshaft 1, that is, a counterweight (counterweight) other than the end portions (counterweights 51 and 58) among a plurality of counterweights. It is preferable to be attached to any one of 52 to 57).

1 is a schematic cross-sectional view showing a main part of an internal combustion engine to which a crankshaft according to Embodiment 1 of the present invention is applied. The schematic perspective view which shows the state by which the piston was attached to the crankshaft which concerns on Example 1 of this invention. Schematic which shows the AA cross section shown in FIG. The schematic perspective view of the principal part of the crankshaft shown in FIG. The schematic sectional drawing which shows the principal part of the internal combustion engine to which the crankshaft which concerns on Example 2 of this invention is applied. Schematic of the principal part of the crankshaft shown in FIG. The schematic perspective view of the crankshaft shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Crankshaft 2 Crankpin 3 Crank journal 4 Crank arm 5 (51-58) Counterweight 5a Mounting part 5b Outer peripheral surface 6,60 Sensing rotor 6a Mounting hole 6b, 62 Side surface 61 Mounting part 7 Detected part 8 Protrusion 9 Mounting screw 9a Screw head 10 Weight mass 100 Internal combustion engine 101 Cylinder block 101a Wall surface 102 Lower crankcase 103 Connecting rod 104 Piston 105 Cylinder 106 Sensor

Claims (5)

In the rotor for detecting rotation of the crankshaft provided with the detected portion whose rotation is detected by the rotation detecting means,
A rotor for rotation detection, characterized in that a weight for adjusting the balance of the crankshaft is provided in the rotor body. The rotation detection rotor according to claim 1 is constituted by a thin plate-like member, and the attachment member is connected to the rotor attachment portion provided on the counterweight side portion of the crankshaft via the rotation detection rotor. It is fixed by being locked to,
The rotation detection rotor, wherein the weight is provided to the vicinity of an end portion in the axial direction of the attachment member when the rotation detection rotor is attached to the rotor attachment portion by the attachment member. In the rotor for detecting the rotation of the crankshaft constituted by a thin plate-like member having a detected portion whose rotation is detected by the rotation detecting means and attached to the counterweight of the crankshaft,
A rotation detecting rotor, comprising: an attachment portion provided on a part of the rotor body and attached to an outer peripheral surface of the counterweight by an attachment member when attached to a counterweight of a crankshaft. The crankshaft is provided with a plurality of counterweights in the axial direction,
The rotation detection rotor according to claim 1, wherein the rotation detection rotor is attached to a counterweight provided in a central region of the plurality of counterweights.   A crankshaft characterized in that the rotation detection rotor according to any one of claims 1 to 4 is attached and fixed to a counterweight.

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