贾新光：日本政府曾经建设三大汽车集团
——摘自搜狐网(http://auto.sohu.com)
20世纪50年代中期，日本汽车市场进入高速发展时期，而经历了复杂的兼并、重组，形成10厂的汽车工业体系（那时三菱尚未独立，本田尚未生产汽车），轿车生产也从合作引进、来件组装方式转向建立大批量国产化生产的方式，在各汽车厂间展开了设备投资竞争。
日本在战后使用了各种各样的政策手段，保护和发展钢铁、化工、机械、半导体等“支柱”产业，由于这些产业具有显著的规模经济特征，政府常常以在此类产业中易产生“过度竞争”，可能使全部企业一同倒下为理由，对国内产业采取保护政策，通过行政指导实施进入管制、投资调整、促进合并、合理化卡特尔等措施。
为了促进日本汽车工业的自主发展，日本通产省在1961年5月在产业合理化审议会上，提出了“将国内汽车制造厂家改组为三大集团”的方针，在日本产业界引起强烈的反响。当时日本国产车的开发、产品性能、价格都无法与国外汽车行业相比，因此日本业界部分人士强烈主张通过集团化来增强日本汽车工业的竞争力。
日本通产省“三大集团”的设想是，将当时的8家汽车制造厂分别组建成大批量生产、小型车生产、特种车三个生产集团，同时禁止其他企业再进入汽车行业。
但是，这个设想也有一些阻力。比如法律障碍。战后，日本颁布了《独占禁止法》（相当于美国的反垄断法），鼓励正当竞争，避免某个行业为一个企业所垄断，并促进产业国际化。《独占禁止法》的监察部门是日本公正取引委员会，任何公司的合并都要经过这个委员会的审批。王子汽车厂曾找丰田公司提出合并愿望，由于当时王子汽车厂的经营状况不太好，因此丰田公司委婉地拒绝了。除了怕背包袱，也因为担心通不过《独占禁止法》。后来日本公正取引委员会批准...
更多-> |
|
Home
> Product
and How-To Information > Product
and How-To Information: C > Product
| Camshaft Gear |
 |
|
|
|
If the camshaft and crankshaft
drive gears require replacement, this can be done
with the engine in the car. Manufacturers of engines
with pressed-fit camshaft gears make special tools
that can be used to hold the cam forward during gear
installation.
|
If the cam sprocket is the nylon type and
chunks of gear teeth are missing, the oil
pan must be removed in order to extract
teeth from the oil pump screen and oil pan.
|
This oil pump sprocket is
filled with the teeth of a nylon timing sprocket
that failed.
Replacing A
Camshaft Gear
When replacing a
pressed-fit camshaft gear, use a puller to
remove it from the cam.
- Disconnect the
negative battery cable.
- Remove the covers
protecting the camshaft drive gears.
- Check for proper
alignment of the timing marks on the
timing gears.
- Remove the timing
gears according to the service manual.
- Clean the timing
gears.
- Inspect the gears
for wear or cracks, and replace
necessary parts.
- After replacing any
worn or damaged gears and drives, set
the timing marks according to the
service manual.
- Rotate the engine
through two complete rotations of the
crankshaft. Check to see if the timing
marks on the gears are still in proper
alignment.
- Reinstall all
covers removed for access.
- Reconnect the
negative battery cable and start the
engine.
- Set the ignition
timing to the manufacturer's
specifications.
|
Installing A
Camshaft Gear
When reinstalling the
gear, take care that the cam does not move
to the rear; it could knock loose the core
plug in the rear of the block or chip cam
lobes on neighboring lifters.
- The rear of the cam
gear must be supported while the cam is
pressed from its center.
- After the new cam
gear is pressed on, end play is checked
with a feeler gauge.
Checking the
clearance behind the thrust plate to
determine camshaft end play. Courtesy of
Federal Motors Corporation, Service
Technology Group.
- The clearance
between a cam thrust plate and the
sprocket or gear varies from
0.0015" to 0.005".
- If a spacer is
used, it must be from 0.0015" to
0.005" thicker than the thrust
plate.
- The cam will press
against the spacer, which fits inside
the thrust plate hole, controlling end
thrust.
- In some cases,
adjustment is made by replacing the
thrust plate.
- Some engines limit
the end play of the camshaft through the
use of a cam button.
- A nylon button or
torrington bearing sets on a spring and
is installed between the camshaft timing
gear and the timing chain cover.
- Aluminum gears can
be heated for easier installation.
|
Do not forget the spacer on a cam
with a bolt-on sprocket. The result
could be a cam that will not turn
after the bolt is tightened.
|
|
|
|
|
|
| 相关零件: |
|
|
|
|
|
|
返回顶部.
|
|
|
|
|
|
