JPH0451943Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention aims to improve the orientation of a piston in which the axis of the piston pin engagement hole does not intersect with the axis of the piston but is offset in the radial direction of the piston. The present invention relates to a piston direction adjusting device that detects, determines and positions a piston via the piston pin engagement hole using a detection device.

(Problems to be solved by conventional techniques and ideas) Pistons used in engines of automobiles, motorcycles, etc. are attached to the crank arm of a crankshaft via connecting rods, but when the piston moves back and forth inside the cylinder, Since the connecting rod is disposed obliquely with respect to the piston axis, the piston receives a large surface pressure from the cylinder side wall.

This surface pressure increases especially when the piston retreats inside the cylinder due to the engine's explosion process.
In order to alleviate this surface pressure as much as possible and prevent noise, etc., the axis of the piston pin that connects the piston and connecting rod does not intersect with the axis of the piston, and the axis of the piston pin that connects the piston and connecting rod does not intersect with the axis of the piston. It is installed with a slight deviation (about a few mm) from the

Therefore, the position of the piston pin engagement hole of the piston is also offset with respect to the piston axis. It is necessary to properly position the matching hole.

When assembling the piston and connecting rod, place the connecting rod on the assembly pallet with the through hole at its small end facing up and down, and then install the piston on the extension of the connecting rod axis on the small end side of the connecting rod. The piston is placed with its head facing down, and the axis of the piston is offset from the extension line of the connecting rod shaft by the amount of deviation of the piston pin engagement hole.When assembling the connecting rod to the piston, It is necessary to accurately and quickly align the axis of the pin engagement hole and the connecting rod shaft at least on the same vertical plane.

The present invention has been made in view of the above points, and its purpose is to provide a piston direction adjustment device that positions the piston by orienting the piston pin engagement hole in a predetermined direction accurately and quickly. There is something to do.

(Means for solving the problem) A means for solving the above problem is to provide a piston in which the axis of the piston pin engagement hole does not intersect with the piston axis but is offset in the radial direction of the piston. is rotated around its axis, and the direction of the piston pin engagement hole is detected via the piston pin engagement hole by two detection parts having a receiving and transmitting function arranged on both sides of the piston of the detection device. In a piston direction adjusting device that determines the direction of the piston and positions it by stopping the rotation of the piston, the axis connecting the two detection parts of the detection device is defined as the diameter of the piston including the axis of the piston pin engagement hole. On the directional plane,
The direction of the piston pin engagement hole is arranged in the desired direction, and the axis connecting the detection section is shifted to the side where positioning is desired with respect to the piston axis, and the axis connecting the detection section is aligned with the piston axis. The inner surface of the piston pin engagement hole on the side farther from the plane parallel to the axis of the piston pin engagement hole is disposed along the position through which the piston rotates.

(Function) Direct the axis connecting the two detection parts of the detection device to the desired direction of the piston pin engagement hole, and direct this axis to the inner surface of the piston pin engagement hole on the side farther from the piston axis on the desired eccentric side. Because the piston is arranged along the axis, when the piston pin engagement hole is oriented in the desired direction by rotating the piston once around its axis, a signal emitted from the transmitter side of the detection device is sent to the receiving side. This allows the piston pin engaging hole to be oriented in a desired direction.

(Embodiments) Next, preferred embodiments of the present invention will be described in detail with reference to the attached FIGS. 1 to 5.

First, an example of the piston 1 and connecting rod 10 in this embodiment will be explained with reference to FIG.
Piston rings 5, . 1, the piston pin engagement hole 3,
Notches 4, 4 are formed in which the third side is cut out in an arc shape.

The connecting rod 10 connects the small end 13 with a through hole 13a forming a connection hole with the piston 1, the large end 11 with a connection hole 11a with the crankshaft, and the large and small ends 11 and 13. The connecting rod small end 13 is inserted into the piston recess 2 between the piston pin engagement holes 3 and 3 of the piston 1, and the connecting rod small end 13 is inserted into the through hole 13a of the piston 1 and the piston pin of the piston 1. By inserting and engaging the piston pin 6 into the engagement holes 3, 3, the piston 1 and connecting rod 10 are connected. Note that 7 is a clip for regulating the movement of the piston pin 6, and 14 is an oil scraper portion of the connecting rod 10.

The piston 1 and connecting rod 10 described above are positioned and placed on an assembly pallet P and conveyed on a conveyor C.
After the orientation of piston 3 is finally determined, the piston 1 and connecting rod 10 will be assembled to each other, but the positions of the piston 1 and connecting rod 10 on the assembly pallet P before being carried into the piston direction adjustment device 20 will be determined. The relationship will be explained with reference to FIG.

The piston 1 is positioned on the assembly pallet P in an upright state with its head portion 1a facing down, and the orientation of the piston pin engagement holes 3, 3 has not yet been determined. Here, the axis l of the piston pin engagement holes 3, 3 is orthogonal to the axis m of the piston 1, but they do not intersect, and are arranged at a position shifted by an amount of deviation t to one side in the radial direction of the piston. , so as to reduce the surface pressure between the piston 1 and the cylinder wall when the piston 1 moves within the cylinder.

The connecting rod 10 is arranged so that the small end 13 faces the piston 1 side, the through hole 13 of the small end 13 faces in the vertical direction, and the piston 1 and the connecting rod 10 are arranged in a substantially straight line from front to back. It is positioned and placed horizontally on the assembly pallet P.
Here, the connecting rod 10 has a through hole 13 in the small end 13.
The connecting rod axis n in the front-back direction connecting the center of the connecting hole 11a of the large end 11 and the center of the connecting hole 11a of the large end 11 is aligned with the piston pin engaging hole 3, with respect to the piston axis m.
The connecting rod 10 is positioned so as to be deviated toward the oil scraper 14 side by a displacement amount t of 3, and when the piston and the connecting rod 10 are assembled, the connecting rod axis n and the axis l of the piston pin engagement holes 3, It is necessary to align the parts horizontally on the assembly pallet P as shown in FIG.

Next, grasp the piston 1 on the assembly pallet P, rotate it around its axis m, and align the horizontal position of the axis l of the piston pin engagement holes 3, 3 with the connecting rod axis n. The direction adjustment device 20 will be explained with reference to FIGS. 3 to 5.

The piston pin direction regulating device 20 is mounted on a support frame 2.
1. It consists of a support plate 22, a vertically movable table 23, a rotation shaft 25, a rotation drive source 32, a gripping device 28 for the piston 1, a detection device, etc., and is located above the conveyor C arranged in the front-rear direction as shown in Fig. 4. A support frame 21 is disposed so as to straddle the conveyor C. A support plate 22 is fixed to a horizontal upper beam 21a disposed in the left-right direction of the support frame 21, and two parallel rods 2 of a vertically movable table 23 are attached to a guide portion 22a of the support plate 22.
3a (one of which is not shown in the figure) is inserted through the vertically movable base 23 so as to be slidable in the vertical direction.
is elastically biased upward by a spring member 24 disposed between the support plate 22 and the support plate 22 . In addition, the vertical movement table 23
can be moved up and down by a drive source (not shown).

The vertically movable table 23 extends vertically and has the rod 23a on its inside, and has a support portion 23b on its outside. The rotary shaft 25 is rotatably supported, with an upper part supported by a thrust bearing 27 via a ring member 26, and a lower part supporting a gripping device 28 for the piston 1. The gripping device 28 is capable of gripping the outer side of the piston 1 by opening and closing the lower portions of two gripping plates 30 and 30 inwardly and outwardly using a drive source 29. Further, a rotary drive source 32 is connected to the vertically movable table 23 via a support member 31.
is supported with its rotary drive shaft 32a facing downward, and the rotary drive shaft 32a and the upper end 25a of the rotary shaft 25 are connected via a coupling 33.
3. The gripping device 28 can be slowly rotated in a predetermined direction via the rotating shaft 25.

Further, the upper and lower beams 21b, 21b of the support frame 21
A rectangular support frame 34 is horizontally attached to the middle part of the gripping device 28 side, and the front and rear members 34a and 34b of the support frame 34 have a detection section 35 of a detection device (for example, a phototube device) in the front and rear direction. 35 (one side is a light emitting part and the other is a light receiving part) are installed horizontally. This detection device is used to accurately align the direction of the piston pin engagement holes 3, 3 of the piston 1 with the direction of the light beam emitted from one of the detection parts 35, 35.

That is, the piston 1 is held with its head portion 1a facing down and held at a predetermined height via the gripping device 28 and the vertically movable table 23, that is, the height of the axis l of the piston pin engagement holes 3, 3, as shown in FIG. Detection unit 3 of the detection device
After lifting the piston 1 to a height that substantially matches the height of the optical axes of the pistons 5 and 35, the piston 1 is moved to the rotational drive source 32.
rotates around its axis m, and detects the detection parts 35, 35 of the detection device via the piston pin engagement holes 3, 3.
When the light beam emitted from one side is caught by the other side, the rotation of the piston 1 is stopped and the direction of the piston pin engagement holes 3, 3 is accurately aligned with the direction of the light beam of the detection parts 35, 35. It is.

Here, since the piston pin engagement holes 3, 3 have a predetermined size, simply the detection part 35 of the detection device,
The orientation of the piston pin engaging holes 3, 3 cannot be determined accurately only by emitting and receiving light between the piston pins 35 and 35.
Therefore, the detection parts 35, 35 of the detection device emit light,
If the light is received along the inner surface of the piston pin engaging holes 3, 3, it is possible to determine the accurate orientation of the piston pin engaging holes 3, 3.
Since the axis l of 3 does not intersect the piston axis m and is eccentric by a predetermined distance t, the optical axes of the detection parts 35, 35 need to be aligned with the inner surfaces of the piston pin engagement holes 3, 3 on the eccentric side. There is.

That is, as shown in FIG. 5, the detection parts 35, 35 are aligned in the desired direction of the piston pin engagement holes 3, 3, and the axis connecting the detection parts 35, 35 is aligned with the piston axis m. Position the pin engagement holes 3, 3 by shifting them to the desired side,
In addition, when the diameter of the piston pin engagement holes 3, 3 is d, the detection portions 35, 3
5 is located on the piston axis line m side by approximately the thickness of the light beam from d/2+t, and is arranged along the inner surface of the piston pin engagement holes 3, 3 rotated in a predetermined direction. By positioning the detection parts 35, 35 so that the piston pin engagement holes 3, 3
can be directed toward the optical axis of the detection units 35, 35, and its eccentric side can be aligned with the piston axis m.
The piston pin engaging holes 3, 3 can be oriented toward the detecting portions 35, 35 with accuracy.

Next, the overall operation of the piston direction adjusting device 20 will be explained.

The assembly pallet P in which the piston 1 and connecting rod 10 are positioned as shown in FIG. It is positioned directly below the gripping device 28, that is, at a position where the piston axis m and the axis of the rotation shaft 25 of the piston direction regulating device 20 coincide.
Next, with the two gripping plates 30, 30 of the gripping device 28 open, the gripping device 28 is lowered by the vertical movement table 23, and the lower ends of the gripping plates 30, 30 are connected to the piston pin engagement hole 3 of the piston 1, 3, the gripping device 28 stops descending, closes the gripping plates 30, 30, and removes the skirt portion 1 of the piston 1.
The vicinity of b is clamped, and the piston 1 is gripped by the gripping device 28.

Next, the gripping device 28 is raised by the vertical movement table 23, and the piston 1 is held in its piston pin engagement holes 3, 3.
is raised until the height of the axis l becomes approximately the same as the height of the optical axes of the detection units 35, 35 of the detection device. Subsequently, the piston 1 is slowly rotated around its axis m by the rotary drive source 32 via the rotation shaft 25 and the gripping device 30. Here, the detection parts 35, 3 of the detection device
5 is positioned so that the eccentric side of the piston pin engagement holes 3, 3 faces toward the oil scraper 14 side of the connecting rod 10 on the assembly pallet P, so that the piston pin engaging holes 3, 3 Axis line n
When the piston 1 faces the front-rear direction and its eccentric side is located on the side of the oil scraper part 14 of the connecting rod 10, light is caught on the light-receiving part side of the detection parts 35, 35 of the detection device, and the rotation of the piston 1 is stopped. Thus, the orientation of the piston pin engagement holes 3, 3 of the piston 1 is determined.

Then, in this state, the piston 1 is again placed on the assembly pallet P, and then it is inverted 90 degrees and positioned as shown by the chain line in FIG. While being inserted into the recess 2, the piston pin 6 is inserted into and engaged with the through hole 13a of the connecting rod small end 13 and the piston pin engagement holes 3, 3 of the piston 1, so that the piston 1 and the connecting rod 10 are connected. The Rukoto.

(Effect of the invention) As is clear from the above, according to the invention, the direction of the piston pin engagement hole can be accurately aligned with the direction of the axis between the detection parts of the detection device by simply rotating the piston in a fixed direction. At the same time, the eccentric side of the piston pin engagement hole can be accurately positioned on the detection section side of the detection device with respect to the piston axis.

In addition, the above effects can be achieved by simply rotating the piston once at most, and the task of determining the orientation of the piston pin engagement hole of the piston can also be done quickly.

[Brief explanation of the drawing]

Figure 1 is an explanatory diagram of the connecting rod assembled to the piston, Figure 2 is a diagram showing the positional relationship between the piston and the connecting rod placed on the assembly pallet, and Figure 3 is a side view of the piston direction adjustment device. 4 is a front view of FIG. 3, and FIG. 5 is a sectional view taken along the line A--A in FIG. 3. In the drawings, 1 is a piston, 3 is a piston pin engagement hole, 20...a piston pin direction adjustment device, 35
is the detection part of the detection device, l is the axis of the piston pin engagement hole, and m is the piston axis.

Claims (1)

[Claims for Utility Model Registration] A piston, in which the axis of the piston pin engagement hole does not intersect with the piston axis but is offset in the radial direction of the piston, is rotated about its axis; When the two detecting parts, which are arranged on both sides and have a receiving and transmitting function, detect the direction of the piston pin engaging hole through the piston pin engaging hole, the rotation of the piston is stopped and the direction of the piston is determined. In a piston direction adjustment device for positioning a piston, the direction of the piston pin engagement hole is determined by making the axis connecting the two detection parts of the detection device on the radial surface of the piston including the axis of the piston pin engagement hole. In addition, the axis connecting the detection part is shifted to the side where the positioning is desired with respect to the piston axis, and the axis connecting the detection part is set to the axis of the piston pin engagement hole including the piston axis. 1. A piston direction regulating device, characterized in that the inner surface of the piston pin engagement hole on the side farther from the plane parallel to is disposed along a position through which the piston passes due to rotation.