JPS6336401B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a mounting device for a cam chain tensioner applied to an overhead cam valve type V-type or L-type engine.

Conventionally, in this type of engine, cam chains provided in the front and rear banks are engaged with the crankshaft adjacent to each other in the axial direction, and each tensioner member provided along each of the cam chains is connected to an end portion on the crankshaft side. It is known that each tensioner member is pivotally supported on the crankcase, but in this type, each tensioner member is generally attached to the crankcase with a separate bolt, and this bolting work is difficult. It is relatively troublesome and difficult to assemble, and it is necessary to provide an axial work space inside the crankcase for bolting work.
This is accompanied by the disadvantage that the axial dimension of the engine increases.

It is an object of the present invention to provide a device which eliminates such inconveniences, and in which cam chains provided in the front and rear banks of an overhead cam valve type V-type or L-type engine are mounted on the crankshaft so as to be mutually axially aligned. and each tensioner member provided along each cam chain is pivotally supported on the crankcase at the end on the crankshaft side, in which the end of each tensioner member is pulled out. The present invention is characterized in that a common bracket is provided with housing-shaped shaft supports that can be accommodated differently, and is attached to the crankcase.

Next, one example of implementing the present invention will be explained with reference to attached drawings.

In the drawings, reference numeral 1 indicates an overhead cam valve type V-type engine, and the engine 1 has front and rear banks 2, 2.
A pair of camshafts 4, 4 for intake and exhaust provided in each cylinder head 3, and a crank case 5.
Each cam chain 7, 7 shall be provided, and each cam chain 7,
7 is engaged with the crankshaft 6 adjacently on the inside and outside in the axial direction.

In the drawings, reference numerals 8, 8 indicate tensioner members provided along the respective cam chains 7, 7, and each of the tensioner members 8, 8 is rotatably supported at an end on the side of the crankshaft 6, respectively. A pressing member 9, which is urged inward by a spring 9a, is pivotally attached to the other end by a pin 9b at the tip.

In the drawings, reference numeral 10 indicates a guide member for each of the cam chains 7, 7.

Although the above is not particularly different from the conventional type described above, according to the present invention, each tensioner member 8, 8
A common bracket 12 having housing-shaped shaft supports 11, 11 for storing the ends of the crank case 5 in a freely removable manner is prepared, and this bracket 12 is attached to the crankcase 5.
Each tensioner member 8,
8 can be pivoted.

In addition to what is shown in the drawings, in more detail, the bracket 12 is fixed to a mounting base 5a protruding from the lower inner surface of the crankcase 5 from the mounting opening 15a side of the oil pan 15 with bolts 16. The frame plate 12b is fixed to the substrate 12a by welding or other means, and the substrate 12a is
The frame plate 12b stands up on the inside of the cam chain 7 of the rear bank 2 which is engaged with the axially outer side of the crankshaft 6, and the frame plate 12b is for the cam chain 7 of the front bank 2 which is engaged with the axially inner side of the crankshaft 6. An upper shaft support 11 in a housing shape that accommodates the end of the tensioner member 8 from diagonally forward so as to be freely inserted and removed, and a rear bank 2 offset to the outside in the axial direction of the crankshaft 6 with respect to the upper shaft support 11. The upper shaft support 11 of the frame plate 12b forms a housing-shaped lower shaft support 11 which accommodates the end of the tensioner member 8 for the cam chain 7 in a manner that it can be freely inserted and removed from the diagonal rear side. It is located on the inner surface of the frame plate 12b and is welded to the base plate 12a so that the lower shaft support 11 is located on the outer surface of the base plate 12a.In addition, in the illustrated example, each cam chain 7 is , 7 is configured to closely oppose the circumferential surface of the engagement portion with the crankshaft 6, and the presser portion 13 prevents the respective cam chains 7, 7 from falling off during assembly as described later.

In the drawings, reference numeral 14 indicates a rubber damper inserted into each shaft support 11.

Next, to explain the assembly procedure, first, each cam chain 7, 7 is engaged with the crankshaft 6,
Next, the bracket 12 is attached to the crankcase 5, and according to this, each of the cam chains 7, 7
is prevented from falling off from the crankshaft 6 by a holding part 13 provided on the bracket 12, and when the cam chains 7, 7 are then hooked onto the camshafts 4, 4 above, the cam chains 7, 7 are prevented from coming off from the crankshaft 6 below. There is no problem, and workability is improved.

After the cam chains 7, 7 are hooked up, the tensioner members 8, 8 are inserted into the shaft supports 11, 11 of the bracket 12, and are set in a predetermined position to complete the assembly.

Note that the present invention is of course applicable not only to V-type engines but also to L-type engines.

As described above, according to the present invention, one common bracket is prepared which is provided with each shaft support in the shape of a housing and which accommodates the ends of each tensioner member in a freely removable manner, and this bracket is attached to the crankcase. , there is no need for troublesome work such as bolting to pivotally support each tensioner member, and ease of assembly is improved, and there is no need for axial work space for bolting, making the engine easier to use. This has the effect of making it more compact.

[Brief explanation of the drawing]

Fig. 1 is a partially cut-away plan view of an engine equipped with the device of the present invention, Fig. 2 is a side view cut along the line - - in Fig. 1, and Fig. 3 is one of the brackets used in the device of the present invention.
FIG. 3 is a perspective view of the example in an exploded state. 1...Engine, 2...Front and rear banks, 5...
Crankcase, 6...Crankshaft, 7...
...Cam chain, 8...Tensioner member, 11...
Axial support, 12...bracket, 13...presser section.

Claims (1)

[Claims] 1. Cam chains provided in the front and rear banks of an overhead cam valve type V-type or L-type engine are engaged with the crankshaft adjacent to each other in the axial direction, and the cam chains are aligned along each cam chain. Each of the provided tensioner members is pivotally supported on a crankcase at an end on the crankshaft side, and the crankcase is provided with a housing-shaped shaft support that accommodates the end of each of the tensioner members in a freely removable manner. Common 1
A cam chain tensioner mounting device characterized by mounting two brackets. 2. The cam chain tensioner mounting device according to claim 1, wherein the bracket is provided with a holding portion for preventing the chain from falling off, which is closely opposed to the circumferential surface of the engagement portion of each cam chain with the crankshaft. .