JPS5941299Y2 - Transmission device for water-cooled overhead camshaft engine - Google Patents

Description

[Detailed description of the invention] This invention relates to a transmission device for a water-cooled overhead camshaft engine in which the valve drive camshaft is driven by a timing belt transmission device, and the water pump is driven by a belt transmission device.
To prevent a timing belt transmission from being damaged by dust and to improve its durability.

The basic structure of this type of engine is that the belt transmission device is placed outside the front of the engine body, the timing belt transmission device is placed on the front side, the timing belt transmission device is placed on the rear side, and the timing belt transmission device is covered with a dustproof cover. A flange passage hole is raised, and the input flange of the quarter pump attached to the front part of the engine body passes through this flange passage hole and is positioned in front of the input flange.

If this continues, external dust will enter the dustproof cover through the relatively large-diameter flange passage hole, adhere to the timing belt transmission, and wear out the timing belt transmission, resulting in poor durability of the timing belt transmission.

In order to solve the above-mentioned problem, this idea is to close the flange passage hole with a closure plate formed in the shape of a cap from a flexible material, and to attach this closure plate to the input shaft support boss in the housing of the water pump. It is characterized in that the outer circumferential edge of the closing plate, which is fitted and fixed and spread out in a cap shape, is brought into elastic contact with the inner surface of the peripheral wall of the flange passage hole.

Examples of this invention will be described below based on the drawings.

FIG. 1 is a longitudinal sectional front view of a forced water-cooled overhead camshaft horizontal diesel engine, and FIG. 2 is a plan view.

This engine includes a belt transmission device V and a timing belt transmission device T arranged in front and behind each other outside the front of an engine body 1 consisting of a cylinder block 2, a cylinder head 3, a head cover 4, and a crankcase 5. .

The timing belt transmission T includes a drive gear 11 fixed to the crankshaft 6, an overhead camshaft 8, and vertical gears 11, 1 fixed to the drive shaft 10 of the fuel injection pump 9, respectively.
2. It is composed of a timing belt 13 wrapped around each gear 7, 11, 12, etc.

The timing belt transmission T is covered with a dust cover 14 fixed to the front of the engine body 1 with bolts.

The belt transmission device V includes a drive pulley 15 fixed to the crankshaft 6, a driven pulley fixed to the input shaft 18 of a water pump 170 whose housing 16a is an auxiliary case 16 fixed to the front surface of the cylinder block 2 and the crankcase 5. 19, driven pulley 21 fixed to the generator 20;
and a V-belt 22 wound around these pulleys 15, 19, 21.

Therefore, the overhead valve camshaft 8 and the fuel injection pump 9 are timed driven by the crankshaft 6, and the water pump 17 and the power generation pole 20 are driven.

In the figure, reference numeral 23 is a tension pulley, 24 is a flywheel, 25 is a starter, and 26 is a cooling fan, which is fixed at the front end of the input shaft 18 of the water pump 11.

A hydraulic pump 27 is disposed within the auxiliary case 16, is fixed to the cylinder block 2 and the crankcase 5, and is directly driven by the crankshaft 6.

As shown in FIG. 3, the front wall of the dust cover 140 has a large flange passage hole 29 for the input 7 flange 28 that is fixed in advance to the input shaft 18 of the water pump 170. A closing plate 30 formed in a cap shape with a flexible material such as rubber to close the water pump 1
The input shaft support boss 31 of the first housing 16a is externally fitted and fixed in an airtight manner.

The peripheral part 32 of this closing plate 30 has a flange passage hole 290
It is in elastic contact with the inner surface of the peripheral wall 33.

Therefore, the flange passage hole 29 is completely blocked by the closing plate 30, the input shaft support boss 31, and the bearing 34 of the input shaft 18, so rubber etc. are prevented from entering the dustproof cover 14 from here. .

Note that the driven pulley 19 is formed by bending a sheet metal, and is fixed to the input flange 28 with bolts 35.

36 is a sealing material.

FIG. 4 shows another embodiment of this invention.

This forms a tapered mounting hole 37 in the closing plate 30,
This closing plate 30 is externally fitted in a positioning manner onto an input shaft support boss 31 of the auxiliary case 16 which has a tapered outer shape.

In this way, the peripheral edge 32 of the dustproof cover 14 comes into elastic contact with the inner surface of the peripheral wall 33 of the flange passage hole 290, and the intrusion of dirt and the like into the cover 14 is prevented.

In both of the above embodiments, the closing plate 3
0, but the peripheral wall 33 of the flange passage hole 29
It is conceivable that the housing 16a of the water pump 17 be blocked between the housing 16a of the water pump 17 and the housing 16a of the water pump 17.

In short, this large flange passage hole 29 is
The cover 14 may be closed to prevent dust from entering the dustproof cover 14.

Since this invention is constructed and operates as described above, it has the following effects.

(a) Since the flange passage hole in the dustproof cover is blocked by supporting the blocking plate between the water pump and the inner surface of the peripheral wall of the flange passage hole in a dustproof manner, there is no possibility that dirt will accumulate inside the dustproof cover from this large flange passage hole. Intrusion can be completely prevented.

Thereby, the durability of the timing belt transmission device inside the cover can be increased.

(b) Since the blocking plate is made of a flexible material and is formed into a shade shape and is brought into elastic contact with the inner surface of the dustproof cover, even if the dustproof cover vibrates, the blocking plate follows the dustproof cover and deforms. There is no wear as a seal structure, and good airtightness can be maintained over a long period of time.

←→ Since the flange passage hole is sealed with a closing plate, the flange passage hole can be formed with a large diameter, and it is possible to fix a large diameter flange to the input shaft, which increases the mounting strength of the belt pulley. can be increased.

[Brief explanation of drawings]

The drawings show an embodiment of this invention; Fig. 1 is a longitudinal sectional front view of a water-cooled overhead camshaft engine, Fig. 2 is a plan view, Fig. 3 is an enlarged sectional view of the main parts, and Fig. 4 is another implementation. FIG. 3 is a diagram equivalent to FIG. 3 showing an example. T... Timing belt transmission device, ■... Belt transmission device, 1... Engine body, 6...
... Crankshaft, 14 ... - Dust cover, 17
...Water pump, 18...Manual shaft, 19...Driven boob 1 28...Inlet cuff flange, 29...Flange passage hole , 30...
...Closure plate, 31...Input shaft support boss, 3
2...30 peripheral area, 33...29 peripheral wall.

Claims (1)

[Scope of utility model registration request] Outside the front of the engine body 1 of a forced water-cooled overhead camshaft engine, a belt transmission V is arranged on the front side, a timing belt transmission T is arranged on the rear side, and an overhead valve drive camshaft is connected to the timing belt transmission T. 8 is interlocked and connected to the crankshaft 6, and a water pump 17 is interlocked and connected to the crankshaft 6 by a belt transmission device (■).
The water pump 17 is assembled to the front of the engine body 1,
The driven pulley 19 of the belt transmission device (■) is fixed to the input flange 28 fixed to the input shaft 18 of the water pump 17, the water pump 17 and the timing belt transmission device T are covered with the dustproof cover 14, and the dustproof cover 14 is attached to the engine body. 1, a francine passage hole 29 is formed in the dustproof cover 14 through which the input flange 28 of the water pump 17 passes, and a blocking plate 30 that closes the francine passage hole 29 is fixed to the water pump 1.
The closure plate 30 is formed into a cap shape using a flexible material, and the outer peripheral portion 32 of the closure plate 30 that spreads out in the cap shape is attached to the flange of the dustproof cover 14. A transmission device for a water-cooled overhead camshaft engine, characterized in that it is brought into elastic contact with the inner surface of a peripheral wall 33 of a passage hole 29.