JPS60141436A - Machining for connecting-rod bearing-surface - Google Patents

Abstract

PURPOSE:To prevent the slackness of a nut by making fine the surface roughness of the bearing surface for a bolt and the nut. CONSTITUTION:A conical working roller 3 is attached under a prescribed pressure onto a connecting-rod body (a) and the bearing surface of the cap (b), and in this state, the working roller 3 is rotated on the seat surfaces (e) and (f) and simultaneously revolved, and further the working roller 3 is rotated on the bearing surfaces (b) and (f), and simultaneously a slip is generated during revolution, and each surface roughness of the connecting-rod body (a) and the bearing surface of the base cap (b) is finished fine. Therefore, the frictional resistance moment generated between the tightening surface for a bolt (c) and a nut (d) and the bearing surface for the connecting-rod body (a) and the cap (b) can be increased, and the generation of slackness can be prevented.

Description

[Detailed Description of the Invention] The present invention relates to a connecting rod that is fitted in two parts into the bottle part of a crank shirt 1- of a reciprocating engine and tightened with bolts and nuts, and a processing of the bearing surface of the cap that comes into contact with the bolt or NAND. It is about the method.

B. A connecting rod consisting of a small end that connects to the piston pin of the piston of a conventional reciprocating engine, a big end that connects to the pin part of the crankshaft, and a rond that connects the small end and the big end.
As shown in Fig. 1, A) consists of a connecting rod body (a) in which the small end, rond and big end halves are integrated, and a cap (b) which is the remaining half of the big end. .

And the connecting rod (A) consisting of the above two members
When connecting the pin part of the crankshaft to the connecting rod body (a),
and camp (b), and using Pol 1- (C) and Nando (d), connect the connecting rod body (a
) and the cap (b), the crankshaft and the connecting rod (A) are connected.

When a reciprocating engine in which a piston and a crankshaft are connected by the connecting rod (A) described above is installed in a car, for example, the connecting rod body receives loads caused by road surface conditions, vibrations, and the rotation of the engine itself while the car is running. Bolts (C) and nuts (d) for tightening (a) and its cap (b)
applied as random or periodic fluctuating loads and vibrations. Therefore, the bolt (C) and nut (d) have varying stresses caused by tension and vibration corresponding to random or periodic varying loads and vibrations.

Therefore, the bearing surface (11
1) If the surface roughness of (f) is rough and there are protrusions and troughs in the micron scale on the seating surfaces (e) and (f), the peaks of the seating surfaces (e) and (f) will deteriorate over time due to the "beating action". As time passes, the mountain is crushed and the height of the mountain becomes lower. If this amount exceeds the elongation occurring in the bolt (C), the contact pressure on each contact surface will disappear.

Furthermore, it is natural that gaps in the axial direction in the thread pairs of normal bolts and nuts used to tighten two parts exist due to tightening, removal, and manufacturing reasons, and it is important to ensure that they are tightly matched. It is not common because it has disadvantages. And a bolt (C) and a nut (d) that fasten the connecting rod body (a) and its cap (b).
Noneshi pair is also a type that has a gap.

Therefore, if the contact pressure disappears due to the above-mentioned "beating action" and a gap is generated between Pol) (e) and Oak l-(d), Pol) ((:) and Oak) (d
) (C
) and oak l-(d) may become loose.

The following two methods can be considered as methods for eliminating the above drawbacks.

The first method is to fix the connecting rod body (a) in contact with the tightening surfaces of the bolt (C) and nut (d).
The surface roughness of the seat surface (e) (f) formed on the camp (b) is finished as fine as possible, and the surface roughness of the seat surface (e) (f) is
) to lower the height of peaks and valleys in microns.

Also, as a second method, pol) (C) and su・nodo (d
), the tightening surfaces of the bolt (e) and nut (d) and the seating surface (e) of the connecting rod body (a) and its camp (b) (
f) Increase the moment of frictional resistance generated between

In order to increase this moment of frictional resistance, the bolt (C
) and the tightening surfaces of the nuts (d) to the connecting rod body (a) and its cap (b)' seating surfaces (e) and (f).
When the bolts (C) and sy) (d) are brought into pressure contact with each other, if the contact pressure is applied in an annular manner around the maximum diameter of the tightening surfaces of the bolts (C) and sy) (d), and frictional resistance is generated, the frictional resistance moment I -The value of the frictional resistance moment increases because the radius from the center of the bolt or nut to the annular shape is multiplied by the frictional resistance. Therefore, the seating surfaces (6) and (f) of the connecting rod body (a) and its cap (b), which come into contact with the flat surface of the bolt (C) and nut (d), are not flat, but circular. Ring-shaped eggplant, or approximately pol) (as shown in Figure 2)
C), the tightening surface of the nut (d) may be machined into a conical shape with a slight recess toward the center from the maximum diameter peripheral portion.

However, in order to make the surface roughness of the connecting rod body (a) and its cap (b) seating surfaces (e) and (f) as fine as possible, there are major disadvantages in terms of cost and efficiency. At the same time, with conventional processing equipment, it is extremely difficult to keep the height of the peaks and valleys low in microns.

Also, the connecting rod body (a) and its cap (b)
) The same problem as above occurs when processing the seating surfaces (e) and (f) into an annular or conical shape.

9. Purpose of the Invention To make the surface roughness of the connecting rod body and its cap's bearing surface that comes into contact with the tightening surfaces of bolts and nuts as fine as possible, to keep the height of peaks and valleys in microns low, and at the same time to The present invention provides a finishing method that enables processing a seating surface into a conical shape.

C.9 Constituent of the Invention A conical or conical and barrel-shaped processing roller is held on the tip surface of a Subaroll, which is a processing tool rotationally driven by a machine tool, so as to be able to revolve and rotate, and The roller is pressed against the connecting rod body and the bolt of its cap, or the seat surface that contacts the tightening surface of the NAND, with a predetermined pressure, and in this state, Superoll is rotated, and the processing roller revolves while rotating on the seat surface. By doing this, the connecting rod body and its camp seating surface are finished.

D. Embodiment FIGS. 3 and 4 are drawings showing a processing tool (A) consisting of a processing roller and a Superoll that holds the processing roller used in the present invention, and FIG. 2) is a mandrel integrally formed on the rear end of Superoll (1), and (3) is a predetermined number of mandrels (3 in the drawing) fixed radially on the tip surface of Superoll (1) via a retainer (4).
This is a held processing roller. The processing roller (3
) is rotatably supported by a holder (4) which is rotatably supported by Superoll (1), so Superoll (
When 1) is rotated, it revolves while rotating at the tip of Superoll (1). In addition, the external shape of the processing roller (3) is as follows:
Connecting rod body (a,) and its cap (
In order to finish the bearing surfaces (e) and (f) in b) into a conical shape,
The Subarol (1) is shaped into a conical shape with a larger diameter on the inner peripheral side, or is shaped like a cone and has a barrel shape with its tapered surface shaped like an arc and having a bulge.

FIG. 5 is a drawing showing a holder (5) used when attaching the processing tool (A) to the headstock of a machine tool.
In the figure, (6) is the main spindle attached to the headstock of the machine tool, (
7) is an adapter for adjusting the vertical dimension (m) that is inserted into the main shaft (6) via a rotation stopper key (8) so as to be able to slide vertically, and (9) is a screw at the tip of the adapter for adjusting the vertical dimension (7). It is a locking nut screwed onto the portion (7a), and the bearing surface of the locking nut (9) is brought into contact with the tip surface of the main shaft (6),
The vertical dimension adjustment adapter (7) is positioned by pressing the tip of the push rod (10) screwed on the side of the main shaft (6) to the vertical dimension adjustment adapter (7). (11) is a tool holder (13) into which the mandrel (2) of Superoll (1) described above is inserted into the tip, and into which the rear end is inserted into the vertical dimension adjustment adapter (7) via the rotation stop key (12); ) is the stopper bolt screwed onto the rear end of (12), and (14) is the stopper bolt (13) from the rear end of the vertical dimension adjustment adapter (7). It is a stopper screwed onto the protruding part. (15) is a disc spring for pressure adjustment that is press-fitted between the rear end of the tool holder (11) and the vertical dimension adjustment adapter (7), and the shape spring (15) allows the tool holder (11) to is such that a predetermined amount of pressing force is applied to the lightning toward its tip.

Further, the pressing force is adjusted by adjusting the number of countersunk springs (15).

In the above configuration, when finishing the seating surfaces (e) and (f) of the connecting rod body (a) or the cap (b) using the processing roller (3) according to the present invention,
The holder (5), which holds the machining tool (3) and has the Subarol (1) attached to its tip, is attached to the headstock of the machine tool. In this state, move the processing roller (3) onto the connecting rod body (a) or the seat surface (e) of the cap (b).
) (f) with a predetermined pressure, then the processing roller (
Holder (5) of Superoll (1) holding 3)
) is rotated by rotating. Then, the processing roller (3), which is held between the tip surface of Superoll (1) and the seating surfaces (e) and (f) of the connecting rod body (a) or cap (b),
) rotates on its own axis while being held by the cage (4) on the seat surface (e> or (f'). At this time, the operating point (P) of the processing roller (3) As the processing roller (3) moves, the locus moves in a spiral manner toward the center or outer diameter of the seat surface (e) or (f), as shown by the two-dot chain line in FIG. , operating point (
The processing roller (3) performs an oscillating motion around point P), and performs a sliding motion instead of a rolling motion at points other than the operating point (P).

In this way, the conical or conical and barrel-shaped processing roller (3) is pressed against the seating surfaces (e) and (f) of the connecting rod body (a) or the camp (b) with a predetermined pressure. If the connecting rod body (a) and its cap (b) are rotated on the seat surface (e) or (f) and slipping occurs at the same time, the seat surface (a) <1> of the connecting rod body (a) and its cap (b) The surface roughness of is finely finished, and the height of the peaks and valleys can be reduced in microns, and at the same time, the seat surfaces (e) and (f) can be processed into a conical shape.

E1 Effects of the Invention As mentioned above, a conical or barrel-shaped processing roller is pressed against the connecting rod body and the seat surface of its cap with a predetermined pressure, and processing is carried out in this state. If the processing roller rotates on its own axis on the seat surface and simultaneously revolves, and the processing roller rotates on the seat surface and slips during rotation, the connecting rod body and its (7)
It is possible to finely finish the surface roughness of the seat surface of the T-Yamp, and it is possible to reduce the height of the peaks and troughs that occur on the seat surface in microns, and at the same time, it is possible to process the seat surface into a conical shape. Therefore, if the connecting rod body and the seating surface of its cap are finished using the above processing method, when the connecting rod body and its cap are fastened using bolts and nuts, the tightening surface of the bolt and nut and the connecting rod body will be At the same time, the moment of frictional resistance generated between the cap and the seat surface of the cap can be increased, and at the same time, the peaks of the peaks and valleys that occur on the seat surface are crushed due to the "beating action", and the peaks and valleys that occur on the tightening surface of bolts and nuts are crushed. Since it is possible to prevent the contact pressure from being lost, it is possible to prevent loosening of the bolt and the bolt.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing the shape of the connecting rod body and its cap, Fig. 2 is a sectional view showing the shape of the connecting rod main body or the seating surface of the cap, and Fig. 3 is a front view of the processing tool used in the present invention. Fig. 4 is a side view, Fig. 5 is a partial sectional view showing a holder for attaching a machining tool to a machine tool, and Fig. 16 is a cross-sectional view showing a holder for attaching a machining tool to a machine tool. It is a drawing showing a movement trajectory. (A) Connecting rod, (a) Connecting rod body, (b) Cap, (C)
・Bolt, (d) ・Nando, (e) (f) ・
・Seat surface, (a)...Processing tool, (1)...Suba roll, (3)...Processing roller.

Claims (1)

[Claims] (11) A conical or conical barrel-shaped processing roller is held on the tip surface of a processing tool rotationally driven by a machine tool so as to be able to revolve and rotate, and the processing roller is attached to a bolt of a connecting rod or a NAND. The bearing surface of the connecting rod is machined by pressing the connecting rod against the bearing surface with a predetermined pressure, rotating the processing tool in this state, and rotating and revolving the processing roller on the bearing surface. A method for processing a connecting rod bearing surface.