JPS6055245B2 - Main bearing hole machining centering method for multi-cylinder internal combustion engine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention provides a method for aligning the center of the main shaft of the boring machine with the center of the main bearing hole when finishing the main bearing hole in the crankcase or bed of a multi-cylinder internal combustion engine using a boring machine. This invention relates to a bearing hole machining and centering method.

Conventionally, the following two methods have been generally used as the main bearing hole machining and centering method.

For example, as shown in FIG. 1, a main bearing 1 of a four-cylinder internal combustion engine,
2, 3, and 4 are provided integrally with the bed 5. The first method is to use temporarily finished main bearing holes 1a, 2a, 3a, 4a of each main bearing 1, 2, 3, and 4. A piano wire (not shown) is stretched parallel to the hole core portion of the hole, and the hole core of each main bearing 1, 2, 3, and 4 is determined using this piano wire as a reference. That is, while adjusting and moving the spindle head 6 up and down and left and right (directions perpendicular to the plane of the paper in FIG. 1), the tool holder 1 is measured based on the piano wire.
3, that is, the center of the main shaft 7, and machine the first main bearing hole 1a, then move the main shaft head 6 beyond the main bearing 1 as shown by the arrow (A), and The main shaft 7 is centered by measuring the piano wire as a reference, and the second main bearing hole 2a is machined.
While moving the spindle head 6 in the order of →, centering of the spindle 7 and hole machining are performed for the third main bearing hole 3a and the fourth main bearing hole 4a. Note that 8 is a column of the boring machine, and 9 is a byte. However, in this method, the work of tensioning the piano wire and centering the main shaft 7 by measuring the piano wire as a reference is extremely complicated and inefficient. In addition, in the second method, in order to avoid the trouble of moving the spindle head 6 each time and centering it again as described above, the spindle head 6 is moved after centering the spindle 7 in the first main bearing hole 1a. The upper half of the main bearing (cap) lb, 2b, 3 has been machined without moving it vertically or horizontally.
b, 4b are removed each time, and the spindle head 6 is simply advanced forward, that is, only in the direction of the hole center line, to machine the next main bearing hole.

However, in this method, the caps 1b, 2b, 3b,
The work of disassembling 4b is complicated and inefficient. The purpose of this invention is to solve the above-mentioned conventional drawbacks and to obtain a main bearing hole machining centering method that makes it possible to perform main bearing hole machining centering efficiently. teeth,
Machining of main bearing holes in a multi-cylinder internal combustion engine when boring each temporarily finished main bearing hole of the main bearings coaxially arranged in parallel at a predetermined interval in the crankcase or bed of a multi-cylinder internal combustion engine. In the centering method, a light beam is projected from a projector onto the assumed core line, and an arm is attached to a column that is movable up and down in parallel with the axis of the main bearing, and an arm that is supported by this arm is attached. a spindle head,
A boring machine equipped with a cutting tool that rotates around the main shaft of this spindle head is placed facing from the opposite side of the above-mentioned projector for each main bearing to be machined, and a beam of light is received at the center of the above-mentioned spindle to process the spindle head. The purpose is to move the main bearing hole and center it.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 2 is a side view of a boring machine showing a case where the main bearings 1, 2, 3, and 4, which are integrated with the bed 5 of a four-cylinder internal combustion engine, are drilled using a boring machine, as in FIG. Components common to those in FIG. 1 are given the same reference numerals and their explanations will be omitted. In addition, the second
If you show the cross section from ■-■ in the figure, it is as shown in Figure 3.
is supported by an arm 10 extending from the column 8. The spindle head 6 moves left and right by moving along the arm 10, moves up and down by the up and down movement of the arm 10 relative to the column 8, and also moves up and down in the longitudinal direction of the column 8 (see Fig. 2). It is possible to move in the front-back direction by moving in the left-right direction). Well, main bearings 1, 2, 3,
4, the lower half is cast integrally with the bed 5, and the upper half caps 1b, 2b, 3b, 4b are attached to the lower half side with bolts. The above is the same as before. In the present invention, a projector 12 that emits a laser beam with good convergence is attached to the end of the base 11 in a position-adjustable manner, and a receiver is placed at the center of the tool holder 13 attached to the main shaft 7 (i.e., at the center of the main shaft). 14 is attached, and although not shown, a confirmation lamp that lights up when the light receiver 14 receives light is attached to an easily visible location such as the spindle head 6.

Then, the bed 5, on which the main bearing holes 1a, 2a, 3a, and 4a have been temporarily finished, is moved in the direction of movement of the column 8 to the main bearing 1.
, 2, 3, and 4 are aligned parallel to each other and base 1.
1, the position of the projector 12 is adjusted so that the light beam passes through the center of the main bearing holes 1a and 4a at both ends. The centers of the main bearing holes 1a, 4a at this time may be determined, for example, as the center point of the diameters of the main bearing holes 1a, 4a on the mating surfaces 1c, 4c of the main bearings 1, 4 which are divided into upper and lower parts. Next, while adjusting and moving the spindle head 6 vertically and horizontally, the spindle head 6 is positioned so that the light beam from the projector 12 enters the projector 14, and the main bearing is located at the center of the main shaft 7, that is, the center of rotation of the cutting tool 9. This means that the holes 1a, 2a, 3a, and 4a have been centered.

Note that confirmation of light reception by the light receiver 14 is performed by lighting a confirmation lamp. Next, the main bearing hole 1a is machined while moving the main spindle head 6 forward as shown by the arrow (D). After finishing the machining of the first main bearing hole 1a, the main bearing hole 1a is machined by moving the main spindle head 6 as shown by the arrow (E). 1 to face the second main bearing hole 2a, and adjust and move the spindle head 6 so that the light beam enters the light receiver 14 in the same manner as described above. Perform centering and hole machining.

Thereafter, by similarly moving the spindle head 6 as shown by the arrows (to) and (卜), performing centering, and drilling, all the main bearing holes 1a, 2a, 3a, and 4a are completed. . Fourth
The figure shows another embodiment, in which a hole 20a of, for example, about 1/100 mφ is made in the center of a tool holder 20, and a light receiver 21 is attached to the center of the hole 20a.

22 is a main shaft, and 23 is a cutting tool.

In this case, when the light beam passes through the hole 20a, the center of the main axis 7 is centered with an extremely high precision of 1/100 TIn, which, together with the convergence of the laser beam, is superior to that of a normal commercially available light receiver. High precision centering that far exceeds resolution is possible.

5 and 6 show another embodiment, in which a center mark 31 is attached to the center of the tool holder 30, and a television camera 32 is installed on the side so as to photograph the front surface of the tool holder 30. Television receiver 33 installed in a position where workers can easily see it
The image is projected onto the screen 33a, and while the operator is looking at the screen 33a, the center mark 31 of the tool holder 30 is aligned with the irradiation point 3 of the light beam.
The spindle head 6 is adjusted and moved so as to match the angle 4.

35 is a main shaft, and 36 is a cutting tool.

According to this method, the positional deviation between the center of the tool holder 30 and the irradiation point of the light beam can be seen magnified before the eyes, so the operation of adjusting and moving the spindle head 6 to make them coincide is extremely easy. It's easy.

Note that the above embodiment is for a four-cylinder internal combustion engine in which the main bearings 1, 2, 3, and 4 are integrated with the bed 5, but a multi-cylinder internal combustion engine in which the main bearings are integrated in the crankcase is also applicable. Needless to say, it can be applied in general.

As explained above, the present invention projects a light beam so that it passes through the center of the main bearing hole that has been temporarily finished, and adjusts the spindle head so that the light beam illuminates the center of the spindle of the boring machine. Since the main bearing hole is machined and centered by moving it, there is no need for the complexity of performing centering while measuring using a piano wire as a reference, making it extremely easy, efficient, and cost-effective. Accurate centering can be performed, and there is no need for complicated work such as disassembling the finished main bearing cap each time, resulting in a significant reduction in man-hours. Moreover, the light beam of the floodlight is directed into multiple main bearing holes.
Since the light is emitted from the hole center of one main bearing hole in the front to the hole center of the other main bearing hole in the front, it not only makes it easy and accurate to set the hole center, but also The hole centers of the main bearing holes of the plurality of main bearings can be completely aligned as a whole. For example, the main bearing hole is relatively small, and it is not possible to install a bar that passes through the main bearing hole and rotate the tool around the bar, so a boring machine is required for each main bearing hole. Even if you have to move it, you can easily and more accurately center it.

[Brief explanation of the drawing]

Fig. 1 is a side view of a boring machine showing a conventional method, Fig. 2 and the following shows an embodiment of the method of the present invention, Fig. 2 is a side view of a boring machine, and Fig. 3 is a side view of the boring machine shown in Fig. 2. 4 is a partially cutaway side view of the tool holder showing another embodiment, FIG. 5 is a side view of the vicinity of the tool holder showing another embodiment, and FIG. FIG. 6 is a front view of the television receiver related to the embodiment in FIG. 5; 1, 2, 3, 4... Main bearing, 1a, 2a, 3a, 4a
...Main bearing hole, 5...Bed, 6...Spindle head, 7
, 22, 35... Main shaft, 9, 23, 36... Bit, 12... Emitter, 13, 20, 30... Bit holder, 14, 21... Light receiver.

Claims (1)

[Claims] 1 Temporarily finished main bearing holes 1a, 2a, 3a, 4a of main bearings 1, 2, 3, 4 arranged in parallel at predetermined intervals in the crankcase or bed 5 of a multi-cylinder internal combustion engine
In the main bearing hole centering method for a multi-cylinder internal combustion engine when boring
An arm 10 that emits a light beam and is movable up and down on a column 8 configured to be movable parallel to the axes of the main bearings 1, 2, 3, and 4, and a main shaft supported by this arm 10. A boring machine equipped with a head 6 and a cutting tool 9 that rotates around the main shaft 7 of the main spindle head 6 is placed facing each of the main bearings 1, 2, 3, and 4 to be machined from the opposite side of the projector 12. A method for machining and centering a main bearing hole in a multi-cylinder internal combustion engine, characterized in that a light beam is received at the center of the main shaft 7 to move the main shaft head 6 during processing.