VARIABLE VALVE TIMING CONTROL APPARATUS
A variable valve timing control apparatus, includes a housing rotating in synchronization with a drive shaft of an internal combustion engine, an inner rotor arranged coaxially with the housing and rotatable relative to the housing, a driven shaft, an intermediate member arranged between the inner rotor and the driven shaft and rotating in synchronization with the inner rotor and the driven shaft, a first hydraulic fluid passage, an inner room formed between the driven shaft and the inner rotor and constituting a portion of the first hydraulic fluid passage, a second hydraulic fluid passage, a passage formed in the intermediate member and constituting a portion of the second hydraulic fluid passage, and a contact portion at which an axial surface of the intermediate member is entirely in contact with the inner rotor between the first hydraulic fluid passage and the second hydraulic fluid passage.
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This application is based on and claims priority under 35 U.S.C. §119 to Japanese Patent Application 2010-203234, filed on Sep. 10, 2010, the entire content of which is incorporated herein by reference.
TECHNICAL FIELDThis disclosure generally relates to a variable valve timing control apparatus.
BACKGROUND DISCUSSIONA known variable valve timing control apparatus (cam timing device for an internal combustion engine) is disclosed in JP3965051B (hereinafter referred to as Reference 1). In the known variable valve timing control apparatus, an inner rotor (inner body in Reference 1) is fixed to a cam shaft by a shaft member such as a bolt (clamping screw in Reference 1). Two passages are formed between the inner rotor and the cam shaft so as to be positioned away from each other in an axial direction (a rotational axis) of the cam shaft.
According to the known variable valve timing control apparatus configured as described above in Reference 1, the inner rotor and the shaft member need to be made of materials having the approximately same linear expansion coefficients in order to inhibit oil supplied to the variable valve timing control apparatus form leaking therefrom to the outer side. Meanwhile, a threaded portion of the shaft member is required to have a sufficient strength. Therefore, the shaft member is generally made of a high-strength material. For example, in a case where the shaft member is being inserted into a central bore of the inner rotor so as to be screwed with the cam shaft, the inner rotor needs to be inhibited from being damaged by the high-strength material of the shaft member. As a result, the inner rotor is recommended to be made of a high-strength material having the approximately same liner expansion coefficient as that of the high-strength material of the shaft member.
However, the inner rotor does not need to be made of the high-strength material as long as the inner rotor is inhibited from being damaged by the shaft member. Utilization of the high-strength material to form the inner rotor makes further processing of the inner rotor difficult. In addition, the weight and cost of the inner rotor may increase.
A need thus exists for a variable valve timing control apparatus, which is not susceptible to the drawback mentioned above.
SUMMARYAccording to an aspect of this disclosure, a variable valve timing control apparatus includes a housing rotating in synchronization with a drive shaft of an internal combustion engine and including an outer rotor, an inner rotor arranged coaxially with the housing and rotatable relative to the housing, a driven shaft to which the rotation of the inner rotor is transmitted, an intermediate member arranged between the inner rotor and the driven shaft along a rotational axis of the driven shaft and rotating in synchronization with the inner rotor and the driven shaft, a first hydraulic fluid passage, an inner room formed between the driven shaft and the inner rotor and constituting a portion of the first hydraulic fluid passage, a second hydraulic fluid passage, a passage formed in the intermediate member and constituting a portion of the second hydraulic fluid passage, and a contact portion at which an axial surface of the intermediate member is entirely in contact with the inner rotor between the first hydraulic fluid passage and the second hydraulic fluid passage along the rotational axis.
The foregoing and additional features and characteristics of this disclosure will become more apparent from the following detailed description considered with the reference to the accompanying drawings, wherein:
First and second embodiments of a variable valve timing control apparatus of this disclosure will be explained as follows with reference to illustrations of the attached drawings. In each of the first and second embodiments, the variable valve timing control apparatus is arranged at a suction valve in an engine E for a vehicle. The engine E for the vehicle in each of the first and second embodiments corresponds to an internal combustion engine.
[Overall configuration] As illustrated in
[Housing and inner rotor] As shown in
The crank shaft C is rotationally driven and a driving force of the crank shaft C is transmitted via a driving force transmission member 102 to the timing sprocket 15. Then, the housing 1 rotates in a rotating direction indicated by an arrow S in
As illustrated in
Oil (hydraulic fluid) is supplied to and discharged from the advanced angle chambers 41 and the retarded angle chambers 42, or the supply/discharge of the oil to/from the advanced angle chambers 41 and the retarded angle chambers 42 is stopped. Therefore, a hydraulic pressure of the oil is applied to the protruding portions 21. Thus, a relative rotational phase between the housing 1 and the inner rotor 2 is shifted in an advanced angle direction or a retarded angle direction, or is maintained in any desired phase. The advanced angle direction indicated by an arrow S1 in
[Lock mechanism] The variable valve timing control apparatus includes a lock mechanism 8 that may lock the relative rotational phase of the inner rotor 2 to the housing 1 at a predetermined phase between the most advanced angle phase and the most retarded angle phase (the predetermined phase will be hereinafter referred to as a lock phase). In a state where the hydraulic pressure of the oil is not stable right after the engine E starts, the lock mechanism 8 locks the relative rotational phase at the lock phase, thereby appropriately maintaining a rotational phase of the cam shaft 101 relative to a rotational phase of the crank shaft C. As a result, a stable rotating speed of the engine E may be obtained.
As illustrated in
[OCV (oil control valve)] As illustrated in
The spool 52 is accommodated in an accommodating portion 5a formed in a first end portion of the OCV bolt 5, which is located at the housing 1. The spool 52 is slidably movable within the accommodating portion 5a along the rotational axis of the cam shaft 101. An external threaded portion 5b is formed at a second end portion of the OCV bolt 5 (the second end portion is axially opposite from the first end portion). The external threaded portion 5b of the OCV bolt 5 is screwed with an internal threaded portion 101a of the cam shaft 101, thereby fixing the OCV bolt 5 to the cam shaft 101.
The spring 53 is arranged in the accommodating portion 5a so as to be in the vicinity of the cam shaft 101, thereby consistently biasing the spool 52 toward an opposite side of the cam shaft 101 along the rotational axis. The electromagnetic solenoid 54 is powered and a push pin 54a arranged at the electromagnetic solenoid 54 axially presses against a rod portion 52a formed at the spool 52. As a result, the spool 52 axially slides toward the cam shaft 101 against a biasing force of the spring 53. A duty ratio of electric power supplied to the electromagnetic solenoid 54 is adjusted, thereby axially adjusting a position of the spool 52 of the OCV 51. A feed amount of the electric power supplied to the electromagnetic solenoid 54 is controlled by an electric control unit (ECU).
[Intermediate member and washer member] As illustrated in
In addition, the washer 7 functions to increase a connecting force of the OCV bolt 5 relative to the cam shaft 101; however, the washer 7 is not an essential component for the variable valve timing control apparatus according to the first embodiment. Alternatively, a component having the same function as the washer 7 and formed into a different shape from the shape of the washer 7 may be utilized in the variable valve timing control apparatus of the first embodiment. In addition, the component may be arranged at a different position from the position of the washer 7 in the first embodiment.
[Configuration of oil passage] As illustrated in
As illustrated in
The oil flowing through the supply passage 45 firstly flows into an annular groove 52b formed at an outer circumferential surface of the spool 52. As illustrated in
In a case where the electromagnetic solenoid 54 is not powered, the spool 52 is maintained in a position shown in
In a case where the electromagnetic solenoid 54 is maximally powered, the spool 52 is maintained in a position shown in
[Effects] In the variable valve timing control apparatus configured as described above in the first embodiment, the intermediate member 6 and the inner room 43b are axially arranged between the OCV bolt 5 and the inner rotor 2. Accordingly, the OCV bolt 5 is not in contact with the inner rotor 2. Consequently, even in a case where the OCV bolt 5 is made of a high-strength material, the inner rotor 2 does not need to be made of a high-strength material in order to inhibit the inner rotor 2 from being damaged by a contact with the OCV volt 5. For example, in a case where the inner rotor 2 is made of an aluminum material, the inner rotor 2 may be easily processed. In addition, the weight and cost of the inner rotor 2 are effectively minimized.
In addition, the variable valve timing control apparatus according to the first embodiment includes the contact portion A at which the axial surface of the intermediate member 6, axially facing the front plate 11 is entirely in contact with the inner rotor 2 between the advanced angle passages 43 and the retarded angle passages 44 along the rotational axis of the cam shaft 101. Accordingly, the oil in the advanced angle passages 43 and the oil in the retarded angle passages 44 are not mixed together with one another in a clearance between the inner rotor 2 and the intermediate member 6. Consequently, controllability of the variable valve timing control apparatus may not deteriorate.
Moreover, for example, the intermediate member 6 is made of a material having a linear expansion coefficient that is substantially equal to or close to a linear expansion coefficient of the material of the OCV bolt 5. In such case, the OCV bolt 5 and the intermediate member 6 are substantially equally swollen under a high-temperature environment, thereby inhibiting the clearance between the OCV bolt 5 and the intermediate member 6 from being increased. As a result, leakage of the oil from the clearance is inhibited and the controllability of the variable valve timing control apparatus may be maintained. For example, in a case where the OCV bolt 5 and the intermediate member 6 are made of iron materials, strength requirements for the OCV bolt 5 and the intermediate member 6 are satisfied. Furthermore, the OCV bolt 5 and the intermediate member 6 appropriately have the substantially same linear expansion coefficients. In addition, the housing 1, the washer 7, the inner rotor 2, the intermediate member 6, and the like are axially fixed to one another by the OCV bolt 5. Accordingly, even in a case where the housing 1, the washer 7, the inner rotor 2, the intermediate member 6, and the like are swollen under the high-temperature environment, a clearance may not be easily generated at the contact portion A between the inner rotor 2 and the intermediate member 6.
The variable valve timing control apparatus according to the second embodiment will be explained as follows with reference to
According to the variable valve timing control apparatus of the second embodiment, the cam shaft 101 penetrates through the central bore of the inner rotor 2 along the rotational axis. The cam shaft 101 serves as the driven shaft. An inner room 101b into which a bolt 91 is inserted is formed in an end portion of the cam shaft 101. An external threaded portion 91 a formed at the bolt 91 is screwed with the internal threaded portion 101a of the cam shaft 101; thereby, the inner rotor 2 arranged in the housing 1 is fixed to the cam shaft 101.
The OCV 51 is arranged at the variable valve timing control apparatus in the first embodiment. On the other hand, the OCV 51 is arranged at the oil pump 62 in the second embodiment. In other words, the OCV 51 controls the oil to be supplied to any of the advanced angle chambers 41 and the retarded angle chambers 42 that will be described below; thereafter, the oil flows into the variable valve timing control apparatus. The supply passage 45 described in the first embodiment is not provided at the variable valve timing control apparatus according to the second embodiment.
The advanced angle passages 73 connecting to the advanced angle chambers 41, respectively and serving as the first hydraulic fluid passages are formed by a passage 73a formed in the cam shaft 101, an inner room 73b formed between the cam shaft 101 and the inner rotor 2, and through-holes 73c formed in the inner rotor 2. Meanwhile, the retarded angle passages 74 connecting to the retarded angle chambers 42, respectively and serving as the second hydraulic fluid passages are formed by passages 74a formed in the cam shaft 101, passages 74b formed in the intermediate member 6, and through-holes 74c formed in the inner rotor 2. The passages 74b serve as passages constituting portions of the retarded angle passages 74.
In the variable valve timing control apparatus configured as described above in the second embodiment, the intermediate member 6 and the inner room 73b constituting a portion of the advanced angle passages 73 are arranged between the cam shaft 101 and the inner rotor 2. Accordingly, the cam shaft 101 is not in contact with the inner rotor 2. Consequently, even in a case where the cam shaft 101 is made of a high-strength material, the inner rotor 2 does not need to be made of a high-strength material in order to inhibit the inner rotor 2 from being damaged by a contact with the cam shaft 101. Moreover, the intermediate member 6 includes the axial surface axially facing the front plate 11 and defined at the contact portion A relative to the inner rotor 2. Therefore, the oil in the advanced angle passages 73 is not mixed together with the oil in the retarded angle passages 74, thereby inhibiting the deterioration of the controllability of the variable valve timing control apparatus.
As described above, the intermediate member 6 includes the axial surface axially facing the front plate 11 and defined at the contact portion A relative to the inner rotor 2, and an axial surface axially facing the rear plate 13 and defined at a contact portion B relative to the inner rotor 2. The contact portion B is arranged between the advanced angle passages 73 and the retarded angle passages 74. The intermediate member 6 is configured so that not only the axial surface defined at the contact portion A but also the axial surface defined at the contact portion B may be entirely in contact with the inner rotor 2 along the rotational axis of the cam shaft 101. As illustrated in
Furthermore, according to the second embodiment, the intermediate member 6 and the cam shaft 101 are press-fitted to each other; thereafter, the inner rotor 2 may be attached to a circumferential outer side of the intermediate member 6. Accordingly, a clearance is inhibited from being axially generated between the intermediate member 6 and the cam shaft 101. For example, in a case where a variable valve timing control apparatus includes an oil passage configuration where a clearance is axially generated between the intermediate member 6 and the cam shaft 101, the oil in the advanced angle passages 73 may be mixed together with the oil in the retarded angle passages 74. In such case, press-fitting the intermediate member 6 to the cam shaft 101 as described in the first embodiment inhibits the clearance from being axially generated between the intermediate member 6 and the cam shaft, therefore not deteriorating the controllability of the variable valve timing control apparatus.
(1) The variable valve timing control apparatus according to each of the first and second embodiments may be adapted to be arranged at an exhaust valve in the engine E. (2) The variable valve timing control apparatus according to each of the first and second embodiments may not include the lock mechanism 8. (3) The oil passage configuration in each of the first and second embodiments may be modified as long as the modified oil passage configuration does not affect the operational function of the variable valve timing control apparatus. (4) According to the first and second embodiments, each of the OCV bolt 5 and the cam shaft 101 serves as the driven shaft. Alternatively, a different member may be adapted as the driven shaft instead of the OCV bolt 5 or the cam shaft 101. (5) The arrangement and shape of the intermediate member 6 described in each of the first and second embodiments may be modified.
The variable valve timing control apparatus according to each of the first and second embodiments of the disclosure may be utilized in the internal combustion engine E for the vehicle and the like.
As described above, according to the first and second embodiments, the variable valve timing control apparatus includes the housing 1 rotating in synchronization with the crank shaft C of the engine E and including the outer rotor 12, the inner rotor 2 arranged coaxially with the housing 1 and rotatable relative to the housing 1, the driven shaft 5, 101 to which the rotation of the inner rotor 2 is transmitted, the intermediate member 6 arranged between the inner rotor 2 and the driven shaft 5, 101 along the rotational axis and rotating in synchronization with the inner rotor 2 and the driven shaft 5, 101, the advanced angle passages 43, 73, the inner room 43b, 73b formed between the driven shaft 5, 101 and the inner rotor 2 and constituting a portion of the advanced angle passages 43, 73, the retarded angle passages 44, 74, the through-hole 44b or the passage 74b formed in the intermediate member 6 and constituting a portion of the retarded angle passages 44, 74, and the contact portions A and B at which the axial surfaces of the intermediate member 6 are entirely in contact with the inner rotor 2 between the advanced angle passages 43, 73 and the retarded angle passages 44, 74 along the rotational axis.
According to the aforementioned configuration, the inner room 43b constituting a portion of the advanced angle passages 43 is arranged between the inner rotor 2 and the driven shaft 5, therefore inhibiting the inner rotor 2 from being in contact with the driven shaft 5. Accordingly, even in a case where the driven shaft 5 is made of the high-strength material, the inner rotor 2 does not need to be made of the high-strength material in order to inhibit the inner rotor 2 from being damaged by the contact with the driven shaft 5. In addition, the variable valve timing control apparatus includes the contact portion A at which the axial surface of the intermediate member 6 is entirely in contact with the inner rotor 2 between the advanced angle passages 43 and the retarded angle passages 44 along the rotational axis of the cam shaft 101. Accordingly, the oil in the advanced angle passages 43 and the oil in the retarded angle passages 44 are not mixed together with one another, thereby inhibiting the deterioration of the controllability of the variable valve timing control apparatus. In addition, the driven shaft 5 may be a bolt for fixing the inner rotor 2 to the cam shaft 101. Alternatively, the driven shaft 5 may be a different member instead of the bolt.
According to the aforementioned first and second embodiments, the intermediate member 6 is made of the material having the linear expansion coefficient that is close to or equal to the linear expansion coefficient of the material of the driven shaft 5 rather than the linear expansion coefficient of the material of the inner rotor 2.
For example, the clearance defined between the intermediate member 6 and the driven shaft 5 in an assembled state is recommended to be maximally reduced while allowing the driven shaft 5 to axially penetrate through the intermediate member 6, in order that leakage of the oil from the clearance may be minimized. However, even in a case where the clearance is maximally reduced in the assembled state of the intermediate member 6 and the driven shaft 5 at a normal temperature, the variable valve timing control apparatus is actually brought in operation and thereafter reaches a high temperature. In such case, the larger a difference between the linear expansion coefficient of the intermediate member 6 and the linear expansion coefficient of the driven shaft 5, the further the clearance between the intermediate member 6 and the driven shaft 5 may be increased. On the other hand, as described above, the material of the intermediate member 6 has the linear expansion coefficient that is close to or equal to the linear expansion coefficient of the material of the driven shaft 5 rather than the linear expansion coefficient of the material of the inner rotor 2. Therefore, the intermediate member 6 and the driven shaft 5 are equally swollen even under the high-temperature environment, thereby inhibiting the clearance between the intermediate member 6 and the driven shaft 5 from being increased.
According to the first embodiment, the oil is supplied to the outer circumferential side of the driven shaft 5 and is supplied via the intermediate member 6 through the retarded angle passages 44 to the inner rotor 2.
Accordingly, the oil may be supplied via the retarded angle passages 44 to the inner rotor 2 without any modification or processing relative to an existing driven shaft of the known variable valve control apparatus. Consequently, even in a case where the intermediate member 6 is additionally arranged at the known variable valve timing control apparatus, the existing driven shaft may be utilized, resulting in a cost reduction.
According to the aforementioned first and second embodiments, the driven shaft 5 and the intermediate member 6 are made of the iron materials and the inner rotor 2 is made of the aluminum material.
Accordingly, both the driven shaft 5 and the intermediate member 6 have high strengths and the substantially equal linear expansion coefficients from each other. Therefore, when the driven shaft 5 is being inserted into the intermediate member 6, the intermediate member 6 is inhibited from being damaged by the driven shaft 5. In addition, the clearance between the driven shaft 5 and the intermediate member 6 may be inhibited from being increased even under the high-temperature environment. Moreover, as described above, the inner rotor 2 is made of the aluminum material. Therefore, the inner rotor 2 may be easily processed and the weight and cost of the inner rotor 2 are effectively minimized.
According to the aforementioned first and second embodiments, the timing sprocket 15 is arranged at the outer rotor 12 and the bearing portion supporting the timing sprocket 15 is arranged at the intermediate member 6.
The bearing portion arranged at the intermediate member 6 for supporting the timing sprocket 15 requires strength. In addition, the bearing portion of the intermediate member 6 is not made of the aluminum material forming the inner rotor 2 but is made of the iron material. Accordingly, abrasion of the bearing portion is appropriately inhibited, therefore improving durability of the variable valve timing control apparatus.
According to the aforementioned second embodiment, the driven shaft 101 corresponds to the cam shaft 101 and the intermediate member 6 is press-fitted to the cam shaft 101.
Accordingly, the clearance between the intermediate member 6 and the cam shaft 101 that serves as the driven shaft is inhibited from being increased, thereby minimizing the leakage of the oil from the clearance.
According to the aforementioned first embodiment, the driven shaft 5 corresponds to the OCV bolt 5 screwed with the cam shaft 101, and a portion of the OCV 51 switching connection and disconnection between the advanced angle passages 43 and the retarded angle passages 44 is accommodated within the OCV bolt 5.
Accordingly, the size of the variable valve timing control apparatus may be reduced. As a result, installability of the variable valve timing control apparatus relative to the engine E may increase.
The principles, preferred embodiment and mode of operation of the present invention have been described in the foregoing specification. However, the invention which is intended to be protected is not to be construed as limited to the particular embodiments disclosed. Further, the embodiments described herein are to be regarded as illustrative rather than restrictive. Variations and changes may be made by others, and equivalents employed, without departing from the spirit of the present invention. Accordingly, it is expressly intended that all such variations, changes and equivalents which fall within the spirit and scope of the present invention as defined in the claims, be embraced thereby.
Claims
1. A variable valve timing control apparatus, comprising:
- a housing rotating in synchronization with a drive shaft of an internal combustion engine and including an outer rotor;
- an inner rotor arranged coaxially with the housing and rotatable relative to the housing;
- a driven shaft to which the rotation of the inner rotor is transmitted;
- an intermediate member arranged between the inner rotor and the driven shaft along a rotational axis of the driven shaft and rotating in synchronization with the inner rotor and the driven shaft;
- a first hydraulic fluid passage;
- an inner room formed between the driven shaft and the inner rotor and constituting a portion of the first hydraulic fluid passage;
- a second hydraulic fluid passage;
- a passage formed in the intermediate member and constituting a portion of the second hydraulic fluid passage; and
- a contact portion at which an axial surface of the intermediate member is entirely in contact with the inner rotor between the first hydraulic fluid passage and the second hydraulic fluid passage along the rotational axis.
2. The variable valve timing control apparatus according to claim 1, wherein the intermediate member is made of a material having a linear expansion coefficient that is close to or equal to a linear expansion coefficient of a material of the driven shaft rather than a linear expansion coefficient of a material of the inner rotor.
3. The variable valve timing control apparatus according to claim 1, wherein a hydraulic fluid is supplied to an outer circumferential side of the driven shaft and is supplied via the intermediate member through the second hydraulic fluid passage to the inner rotor.
4. The variable valve timing control apparatus according to claim 2, wherein a hydraulic fluid is supplied to an outer circumferential side of the driven shaft and is supplied via the intermediate member through the second hydraulic fluid passage to the inner rotor.
5. The variable valve timing control apparatus according to claim 1, wherein the driven shaft and the intermediate member are made of iron materials and the inner rotor is made of an aluminum material.
6. The variable valve timing control apparatus according to claim 2, wherein the driven shaft and the intermediate member are made of iron materials and the inner rotor is made of an aluminum material.
7. The variable valve timing control apparatus according to claim 3, wherein the driven shaft and the intermediate member are made of iron materials and the inner rotor is made of an aluminum material.
8. The variable valve timing control apparatus according to claim 5, wherein a timing sprocket is arranged at the outer rotor and a bearing portion supporting the timing sprocket is arranged at the intermediate member.
9. The variable valve timing control apparatus according to claim 6, wherein a timing sprocket is arranged at the outer rotor and a bearing portion supporting the timing sprocket is arranged at the intermediate member.
10. The variable valve timing control apparatus according to claim 7, wherein a timing sprocket is arranged at the outer rotor and a bearing portion supporting the timing sprocket is arranged at the intermediate member.
11. The variable valve timing control apparatus according to claim 1, wherein the driven shaft corresponds to the cam shaft and the intermediate member is press-fitted to the cam shaft.
12. The variable valve timing control apparatus according to claim 2, wherein the driven shaft corresponds to the cam shaft and the intermediate member is press-fitted to the cam shaft.
13. The variable valve timing control apparatus according to claim 3, wherein the driven shaft corresponds to the cam shaft and the intermediate member is press-fitted to the cam shaft.
14. The variable valve timing control apparatus according to claim 5, wherein the driven shaft corresponds to the cam shaft and the intermediate member is press-fitted to the cam shaft.
15. The variable valve timing control apparatus according to claim 1, wherein the driven shaft corresponds to a bolt screwed with the cam shaft, and
- wherein a portion of a control valve switching connection and disconnection between the first hydraulic fluid passage and the second hydraulic fluid passage is accommodated within the bolt.
16. The variable valve timing control apparatus according to claim 2, wherein the driven shaft corresponds to a bolt screwed with the cam shaft, and
- wherein a portion of a control valve switching connection and disconnection between the first hydraulic fluid passage and the second hydraulic fluid passage is accommodated within the bolt.
17. The variable valve timing control apparatus according to claim 3, wherein the driven shaft corresponds to a bolt screwed with the cam shaft, and
- wherein a portion of a control valve switching connection and disconnection between the first hydraulic fluid passage and the second hydraulic fluid passage is accommodated within the bolt.
18. The variable valve timing control apparatus according to claim 5, wherein the driven shaft corresponds to a bolt screwed with the cam shaft, and
- wherein a portion of a control valve switching connection and disconnection between the first hydraulic fluid passage and the second hydraulic fluid passage is accommodated within the bolt.
Type: Application
Filed: Aug 25, 2011
Publication Date: Mar 15, 2012
Applicant: AISIN SEIKI KABUSHIKI KAISHA (Kariya-shi)
Inventors: Kazunari ADACHI (Chiryu-shi), Yuji Noguchi (Obu-shi), Takeo Asahi (Kariya-shi)
Application Number: 13/217,486
International Classification: F01L 1/344 (20060101);