JP5955754B2 - Piston ring shape measuring method and shape measuring apparatus - Google Patents

Description

  The present invention relates to a piston ring shape measuring method and a shape measuring device capable of easily and stably measuring the degree of piston ring twisting that causes twisting during use.

  Recent piston rings are required to prevent blow-by gas and reduce consumption of lubricating oil for the purpose of improving fuel efficiency of the engine. As a piston ring corresponding to such a requirement, a piston ring (also referred to as a twist ring) that is twisted during use has been developed in order to improve sealing performance.

  For example, as shown in FIG. 11, the piston ring has an inner defect portion 6 in which the inner portion of the upper surface 3 of the piston ring 1 is processed, and the twisting action based on the provision of the inner defect portion 6 makes it difficult to use the piston ring. Causes a twist. As shown in FIG. 11A, the twisted piston ring 1 is inclined with respect to the cylinder wall 10 except during the explosion stroke of the engine. On the other hand, as shown in FIG. 11B, during the explosion stroke of the engine, the explosion pressure acts on the upper surface 3 and the inner peripheral surface 5 of the piston ring 1 as the vertical pressure x and the horizontal pressure y. The ring 1 is pushed down to the lower surface 13 of the groove 12 (piston ring groove), the twist is eliminated, and the outer peripheral sliding surface 2 is pressed against the cylinder wall 10 by the horizontal pressure y and the self-expanding force.

  In the piston ring 1 that twists during such use, the shape of the outer peripheral sliding surface 2 is important for suppressing blow-by and reducing oil consumption. For example, when the outer peripheral sliding surface shape is rectangular, as shown in FIG. 11A, the outer peripheral sliding surface 2 slides in the cylinder with the cylinder wall 20 tilted against it. The oil scraping effect can be enhanced. Furthermore, as shown in FIG. 11 (B), the outer peripheral sliding surface 2 is in close contact with the cylinder wall 20 during the engine explosion stroke, so that the airtightness can be improved.

  Such a piston ring is measured to determine whether its outer peripheral sliding surface has been precisely machined into a desired shape, and whether the degree of torsion (for example, the torsion angle) has been machined to a desired degree. Is maintained. Patent Document 1 proposes a method for measuring the shape of a piston ring that twists during use. This technique is a method of directly measuring the shape of the outer peripheral sliding surface, which is a portion that slides on the cylinder wall. Specifically, as shown in FIG. 12 (B), the piston ring 1 to be measured is fixed in a state of being pressed against the flat surface 19a of the surface plate 19, and the outer periphery of the fixed piston ring 1 is fixed. In this method, the sliding surface 2 is measured with a contact-type surface roughness meter 18 and the shape of the outer peripheral sliding surface 2 of the piston ring 1 is measured from the measurement result.

JP 2006-337164 A

  On the other hand, the degree of twist (for example, the twist angle) is preferably evaluated in a state where the piston ring 1 is actually operated. For example, as shown in FIG. It is desirable that measurement be performed in the same state as the state where the cylinder wall 10 is in contact with the cylinder wall 10. Specifically, as shown in FIG. 12A, a measurement ring gauge 16 and a measurement platen 17 that have been machined to a predetermined dimension capable of reproducing the state are prepared, and the measurement ring gauge 16 is measured. In a state of being fixed on the board 17, an operator presses the piston ring 1 into the measurement ring gauge 16 one by one and pushes it onto the measurement surface board 17 to release the pressure, and FIG. ) And the twisted state shown in FIG. 12A are reproduced, and the twist angle θ in that state is measured. The measurement is performed by tracing the measurement line L with a contact-type surface roughness meter, calculating the twist angle θ from the result of the surface roughness, and managing the quality of the degree of twist based on the value.

  However, since such a method performs manual measurement, there is a risk that variations in workers may occur during measurement with a press-fitting pressure or a surface roughness meter. Therefore, in order to measure stably and accurately, it was necessary to improve to eliminate such variation as much as possible.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a piston ring shape measuring method capable of easily and stably measuring the degree of torsion of the piston ring that causes torsion during use. And providing a shape measuring device.

  The piston ring shape measuring method according to the present invention for solving the above problems comprises an outer peripheral sliding surface, an upper surface, a lower surface, and an inner peripheral surface, and has an inner defect portion in which the inner end of the upper surface is processed, A shape measuring method for measuring the degree of torsion of a piston ring that becomes circular when the abutment is closed, and the piston ring is conveyed above the measuring ring gauge while the abutment is gradually closed by a guide member. A transfer step, an insertion step of inserting the piston ring with the abutment closed into the measurement ring gauge with the press-fitting member, a lower surface of the piston ring inserted into the measurement ring gauge, and the measurement ring gauge A surface shape measuring step for continuously measuring the surface shape of the lower surface, and a discharging work for moving the press-fitting member and discharging the measured piston ring from the measuring ring gauge And having a, the.

  According to the present invention, the piston ring inserted into the measuring ring gauge is in the same state as the state in which it strikes against the cylinder wall due to the twisting action caused by the inner defect portion, so the shape of the piston ring is measured in this state. By doing so, it is possible to evaluate an appropriate degree of twist in the actual use state. According to each of the above steps, the piston ring is inserted into the measurement ring gauge, and the reference object (measurement ring is always measured by continuously measuring the surface shape of the lower surface of the piston ring and the lower surface of the measurement ring gauge. Since it can be measured in contrast to a gauge), automation or semi-automation can be realized. As a result, there is no individual difference in measurement, the measurement time can be made constant and shortened, and the repeatability of measurement becomes constant, thereby improving reproducibility. In addition, periodic sampling inspection, 100% inspection, etc. can be arbitrarily selected, and highly reliable shape measurement can be performed. In addition, by collecting the obtained results, highly reliable statistical processing can be realized.

  In the piston ring shape measuring method according to the present invention, when the piston ring is inserted, the measurement ring gauge contacts a base member that aligns the lower surface of the measurement ring gauge and the lower surface of the piston ring on the same plane. It is configured to be. According to the present invention, the lower surface of the piston ring inserted into the measurement ring gauge and the lower surface of the measurement ring gauge can be installed using the base member as a reference surface, so that the lower surface of the piston ring and the lower surface of the measurement ring gauge are continuously connected. Accurate surface shape measurement can be realized with high accuracy.

  In the piston ring shape measuring method according to the present invention, the shape of the piston ring is measured by a contact-type or non-contact-type surface roughness measuring device. According to the present invention, since the shape of the piston ring is measured by the contact type or non-contact type surface roughness measuring device, continuous measurement of the lower surface of the piston ring and the lower surface of the ring gauge for measurement is easily and accurately performed. be able to.

  The piston ring shape measuring method according to the present invention may be configured to include a calculating step of calculating the surface shape change data obtained in the surface shape measuring step and calculating a torsion angle of the piston ring. Good. If the relationship between the measurement result of the surface shape and the twist angle is known, it is not always necessary to calculate the twist angle each time. However, as in the present invention, the twist angle can also be calculated each time.

  In the piston ring shape measuring method according to the present invention, after the discharging step, an alignment step of aligning the direction of the exit of the discharged piston ring may be configured. According to this invention, the piston ring in which the direction of the abutment is aligned can be easily supplied to the next process.

  The piston ring shape measuring apparatus according to the present invention for solving the above-mentioned problems comprises an outer peripheral sliding surface, an upper surface, a lower surface, and an inner peripheral surface, and has an inner defect portion in which the inner end of the upper surface is processed. A shape measuring device for measuring the degree of torsion of a piston ring that becomes circular when closed, comprising a guide member and a conveying member, and the piston ring is connected to a ring gauge for measurement while the abutment is gradually closed. A transport mechanism for transporting the upper part, a press-fitting member and a base member, and an insertion mechanism for inserting the piston ring having a closed end into the measurement ring gauge until it contacts the base member, and a surface shape measuring device. A surface shape measuring mechanism for continuously measuring the surface shape of the lower surface of the piston ring inserted into the measuring ring gauge and the lower surface of the measuring ring gauge; and the press-fitting Move the timber, and wherein the piston ring after measurement to have a discharge mechanism for discharging from the measuring ring gauge.

  According to the present invention, automation or semi-automation can be realized, there is no individual difference in measurement, measurement time can be made constant and shortened, measurement repeatability is also made constant, and reproducibility is improved.

  Also in this shape measuring device, the shape measuring device may be configured to be a contact or non-contact type surface roughness measuring device, or the surface shape obtained by the surface shape measuring mechanism. You may comprise so that it may have a calculation apparatus which calculates the data of a change and calculates the torsion angle of the said piston ring.

  According to the piston ring shape measuring method and shape measuring apparatus according to the present invention, it is possible to easily and stably measure the degree of torsion of the piston ring that causes torsion during use. As a result, there is no individual difference in measurement, the measurement time can be made constant and shortened, and the repeatability of measurement becomes constant, thereby improving reproducibility.

It is explanatory drawing of the shape measuring method of the piston ring which concerns on this invention. It is a typical whole front view which shows an example of the shape measuring apparatus of the piston ring which concerns on this invention. It is a typical top view of the shape measuring apparatus shown in FIG. It is explanatory drawing of a conveyance mechanism. It is explanatory drawing of an insertion mechanism. It is a typical front view of a surface shape measuring mechanism. It is explanatory drawing of a surface shape measurement mechanism. It is explanatory drawing of the form measured with a surface roughness meter. It is explanatory drawing of a discharge mechanism. It is explanatory drawing of the alignment mechanism. It is a typical schematic diagram showing an example of a piston ring which generates a twist at the time of use. It is a typical block diagram which shows the example of the conventional measuring method.

  Hereinafter, a piston ring shape measuring method and shape measuring apparatus according to the present invention will be described. The present invention is not limited to the following embodiments, and those having a configuration substantially the same as the technical idea described in the claims of the present invention are included in the technical scope of the present invention. The

[piston ring]
For example, as shown in FIGS. 8 and 11, the piston ring 1 to be measured is a piston ring 1 that is twisted during use, that is, a so-called “twist ring”. The piston ring 1 includes an outer peripheral sliding surface 2, an upper surface 3, a lower surface 4, and an inner peripheral surface 5, and has an inner defect 6 in which an inner end of the upper surface 3 is processed. When the piston ring 1 is installed in the piston ring groove 12 and brought into contact with the cylinder wall 10, the abutment 8 is closed and becomes a circular shape or an annular shape, and is used as a piston ring 1 having a high sealing performance utilizing torsion. Is done.

  As long as the piston ring 1 to be measured is a piston ring that causes torsion, the type thereof is not limited. For example, as illustrated in FIG. 11, the outer peripheral sliding surface 2 may have a rectangular shape, As illustrated in FIGS. 8 and 12, the outer peripheral sliding surface 2 may be an arcuate barrel face, or may have a shape other than that. Further, the processing shape and processing method of the inner defect portion 6 are not particularly limited as long as it is a shape and processing means capable of causing the piston ring 1 to be twisted. Examples of the processing shape of the inner defect portion 6 include shapes of an upper surface internal bevel, a lower surface internal bevel, an upper surface internal step, and a lower surface internal step. Further, the material and surface treatment of the piston ring 1 are not particularly limited, and a known material or a known surface treatment can be applied.

  In the present invention, the degree of twist (for example, the twist angle) of the piston ring 1 is evaluated in a state where the piston ring 1 is actually operated. Specifically, as shown in FIG. 11A, the measurement is performed in the same state as when the piston ring 1 is mounted in the ring groove 12 of the biston 11 and is in contact with the cylinder wall 10. For example, as shown in FIGS. 2 and 8, the measurement ring gauge 41 processed to a predetermined size capable of reproducing the state is fixed on the base member 45, and the press-fitting member is inserted into the measurement ring gauge 41. 42, the piston ring 1 is press-fitted and pushed to the surface of the base member 45, the pushing pressure is released to reproduce the twisted state shown in FIG. 11A, and the surface shape measurement in that state is performed. Evaluate the degree of twist.

  The shape measuring method and the shape measuring device 20 according to the present invention described below can accurately measure the degree of twist of the piston ring 1. Hereinafter, the shape measuring method and the shape measuring apparatus 20 will be described together.

[Shape measuring method and shape measuring apparatus]
As shown in FIGS. 1 to 10, the shape measuring method and the shape measuring device 20 of the piston ring 1 according to the present invention include a conveying step (conveying mechanism 30) for conveying the piston ring 1 to a predetermined position, and the piston ring 1. Is inserted into the measuring ring gauge 41 (insertion mechanism 40), and the surface shape measuring step (surface shape measurement) is performed to continuously measure the surface shape of the lower surface 4 of the piston ring 1 and the lower surface 41a of the measuring ring gauge 41. Mechanism 50) and a discharge step (discharge mechanism 80) for discharging the piston ring 1 after measurement. In addition, as shown in FIG. 1, the calculation process 70 and the alignment process 90 may be added.

  Hereinafter, each process and mechanism will be described.

(Transport process, transport mechanism)
As shown in FIGS. 3 and 4, the conveying step is a step of moving the piston ring 1 on the conveying table 33 while gradually closing the joint 8 with the guide member 32 and conveying the piston ring 1 to above the measuring ring gauge 41. It is. Specifically, the piston ring 1 is transported by the transport mechanism 30 including at least the transport member 31 and the guide member 32.

  The transport member 31 is a member that moves in the direction of the arrow shown in FIGS. 3 and 4 and moves the piston ring 1 to a predetermined position at its tip 31a. The conveyance member 31 is, for example, a flat plate-like vertically long member, and is mounted on the conveyance table 33 so as to be movable. It is preferable that the leading end 31a of the conveying member 31 is processed into a leading end shape that can easily push the piston ring 1 in. The tip shape may be, for example, a V-shaped cut as shown in FIG. 3, a cut that is recessed in a straight line, or a cut that is recessed on a curved surface. In addition, you may be a flat plane in which the notch is not even formed. The operation of the conveying member 31 may be an air cylinder, a hydraulic cylinder, or a linear motion guide device, and is not particularly limited as long as it can reciprocate.

  The piston ring 1 is sent to above the measurement ring gauge 41 by the conveying member 31. The predetermined position is directly above the insertion hole of the measurement ring gauge 41, and the piston ring 1 is fed to just above the insertion hole. Meanwhile, as shown in FIG. 4, it is desirable to gradually close the joint 8 of the piston ring 1 by the guide member 32 that contacts the outer periphery of the piston ring 1. In this way, after the piston ring 1 is arranged at a predetermined position on the measurement ring gauge 41, the piston ring 1 in which the abutment 8 is closed by pressing the press-fitting member 42 from above is directly used as the measurement ring gauge. 41 is inserted.

  As shown in FIG. 4, the guide members 32 are arranged on the left and right sides of the piston ring 1 and act so as to sandwich the piston ring 1 from both sides. In the example of FIG. 4, both guide members 32 on both sides are tapered with respect to the transport direction, but only one may be tapered and the other may be straight. The tapered guide member 32 shown in FIGS. 3 and 4 has a tapered portion 32a and a straight portion 32b, and the straight portion 32b is in contact with the inner peripheral surface (inner peripheral edge) of the measurement ring gauge 41 in plan view. The tapered portion 32a is tapered toward the straight portion 32b.

  The guide member 32 is a plate-like vertically long member, and is detachably mounted on the transport table 33. By providing the guide member 32 in a detachable manner, this method and apparatus can be applied to the piston rings 1 having different sizes. Specifically, for the piston rings 1 having different sizes, the measurement ring gauge 41 is replaced, and the press-fitting member 42 corresponding to the size of the measurement ring gauge 41 is replaced. This can be dealt with by replacing the guide member 32 that can be gradually closed to a size corresponding to the inner diameter.

  In the example of FIG. 4, the abutment 8 is directed to the conveying member 31 side, but may be directed to the near side or the far side. In addition, since the piston ring 1 supplies the aligned piston ring 1 to the shape measuring apparatus 20 in order, it is normally supplied to a conveyance process so that the direction of the abutment 8 may align in one direction. Further, since the abutment 8 faces the right side (conveying member side), the near side, or the far side in the position in plan view of FIG. 4, for example, as shown in FIG. The measuring element 511 of the surface roughness meter 51 provided in is not caught on the abutment 8.

  Although such a guide member 32 is preferably used, it is not an indispensable structure, and the piston ring 1 conveyed above the measurement ring gauge 41 without closing the abutment 8 with the guide member 32 at the time of conveyance, What is necessary is just to be able to close the joint 8 until it press-fits with the press-fitting member 42. For example, if a guide member (not shown) having a large taper shape is provided directly above the measurement ring gauge 41, when the press-fitting member 42 pushes the piston ring 1 from above, the piston ring 1 is moved by the guide member. , The piston ring 1 can be inserted into the ring gauge 41 for measurement. Further, by forming the tapered surface 411 of the measuring ring gauge 41 into a large tapered shape, the tapered surface 411 itself can be used as the guide member 32 at the time of insertion.

(Insertion process, insertion mechanism)
As shown in FIG. 5, the insertion step is a step of inserting the piston ring 1 with the abutment 8 closed into the measurement ring gauge 41 with the press-fitting member 42. The insertion mechanism 40 that performs this step can be performed by the press-fitting member 42, the measurement ring gauge 41, the base member 45 (see FIG. 2), and their driving devices 43 and 46.

  First, as shown in FIG. 5 (A), the base member drive device 46 (see FIG. 2) of the press-fitting member 42 and the base member 45 arranged away from the measurement ring gauge 41 is operated. The base member 45 is moved until it contacts the lower surface 41 a of the measurement ring gauge 41. The base member 45 is provided with a cut portion 49 for a surface roughness meter. The cut portion 49 is provided so that the surface roughness meter 51 can measure the surface roughness at the position, and a cut having a dimension larger than the moving length of the surface roughness meter 51 shown in FIG. 7 is provided. It is a member.

  Before and after that, as shown in FIG. 5B, the piston ring 1 is transported in the transporting process described above, and the piston ring 1 is moved directly above the ring gauge 41 for measurement. Note that the timing at which the base member 45 is brought into contact with the lower surface 41a of the measurement ring gauge 41 and the timing at which the piston ring 1 is moved directly above the measurement ring gauge 41 may be either first or simultaneously. Normally, the piston ring 1 is moved directly above the measurement ring gauge 41, and thereafter, the base member 45 is raised and brought into contact with the measurement ring gauge 41, and then the piston ring 1 is pushed in by the press-fitting member 42. It is performed in the procedure. In any case, it is sufficient that the movement of the base member 45 and the movement of the piston ring 1 are completed before the press-fitting member 42 is pushed down from above.

Next, as shown in FIG. 5C, the driving device 43 of the press-fitting member 42 is operated to push down the press-fitting member 42 from above and push the piston ring 1 into the measurement ring gauge 41. By this operation, the piston ring 1 is inserted into the measurement ring gauge 41 and further pushed in until it hits the base member 45. The pressure of the press-fitting member 42 at this time may be a constant depending on the type of piston ring 1 or the like is not particularly limited, for example, 2 kg / cm ² or more, be in the range of 20 kg / cm ² or less it can. Further, the speed at which the press-fitting member 42 is pushed in is not particularly limited, but can be in the range of several mm / second or more, tens of millimeters or tens of millimeters / second or less.

  Thereafter, the press-fitting member 42 is raised by the driving device 43. The pressure applied to the piston ring 1 is released by the rise of the press-fitting member 42, and the twisted state of the piston ring 1 is reproduced, for example, as shown in FIG. 8, FIG. 11A, or FIG. In this state, surface shape measurement described later is performed.

  Thereafter, the base member 45 is lowered (not shown). The base member 45 includes a surface 47 for aligning the lower surface 4 of the piston ring 1 and the lower surface 41a of the measurement ring gauge 41 on the same plane when the piston ring 1 is inserted into the measurement ring gauge 41. The flatness of the surface 47 needs to be highly accurate. For example, surface grinding or polishing is performed, and the maximum height Ry of JIS B 0601 (1994) is preferably about 6.3 S or less, more preferably about 1.6 S or less, and has high flatness and flatness. This is desirable in that the measurement accuracy with the surface roughness meter 51 can be increased. Further, such a highly accurate base member 45 is a hardened steel (for example, SKD61) having a Rockwell hardness (HRC: using a diamond cone having a tip radius of 0.2 mm and a tip angle of 120 ° and applying a force of 150 kgf) of 40 or more. A material having excellent wear resistance and made of a material such as (material) can be preferably applied.

  The mounting member 48 may be provided with a rotation mechanism so that the base member 45 on which the measurement ring gauge 41 is mounted can rotate in the circumferential direction. In order to make the base member 45 rotatable, it can be easily realized by embedding a bearing or the like in the mounting member 48. By making the base member 45 rotatable, the measurement ring gauge 41 with the piston ring 1 inserted also rotates, so that the measurement site to be measured by the surface roughness meter 51 described later is not a single location, but the piston ring 1. It can be performed at a plurality of locations in the circumferential direction. For example, as shown in FIG. 3, the position of the conveying member 31 on the opposite side of 180 ° is usually measured with the surface roughness meter 51, but other locations can also be measured.

  Thus, the lower surface 4 of the piston ring 1 inserted into the measurement ring gauge 41 and the lower surface 41a of the measurement ring gauge 41 can be installed using the surface 47 of the base member 45 as a reference surface, and the lower surface 4 of the piston ring 1 And continuous measurement of the surface shape of the lower surface 41a of the ring gauge 41 for measurement can be realized with high accuracy, and the shape of the lower surface 4 of the piston ring 1 can be measured with high accuracy.

(Surface shape measurement process, surface shape measurement mechanism)
In the surface shape measurement step, as shown in FIGS. 6 to 8, the surface shape of the lower surface 4 of the piston ring 1 inserted into the measurement ring gauge 41 and the lower surface 41 a of the measurement ring gauge 41 are continuously measured. It is a process. The surface shape measuring mechanism 50 that performs this step includes a surface shape measuring device 51, and continuously forms the shape of the lower surface 4 of the piston ring 1 inserted into the measuring ring gauge 41 and the shape of the lower surface 41a of the measuring ring gauge 41. Measure automatically.

  The surface shape measuring device 51 preferably uses a contact type or non-contact type surface roughness meter 51 as a measuring device. The contact-type or non-contact-type surface roughness meter 51 can easily and accurately perform continuous measurement of the lower surface 4 of the piston ring 1 and the lower surface 41 a of the measurement ring gauge 41.

FIG. 8 is an explanatory diagram showing the operation of the probe 511 of the surface roughness meter 51. The measuring element 511 provided at the tip of the surface roughness meter 51 moves to a predetermined initial position at the time of measurement, and moves upward at that position to enter a measurement start state. As shown in FIG. 8, the predetermined initial position can include a position that further enters the ring center side from the inner peripheral surface 5 of the piston ring 1, but is not necessarily specified as such a position. Thereafter, the measuring element 511 moves in the direction of the arrow in FIG. 8 to start measurement. The measuring element 511 that has started measurement moves in the direction of the arrow so as to trace the lower surface 4 of the piston ring 1 and the lower surface 41a of the measuring ring gauge 41. The pressing pressure of the probe 511 against the lower surface 4 of the piston ring 1 and the lower surface 41a of the measurement ring gauge 41 needs to be a pressure that does not push up the piston ring 1 inserted into the measurement ring gauge 41. It can be in the range of about 1 g / cm ² or more and 30 g / cm ² or less. Moreover, the moving speed of the measuring element 511 in the arrow direction can be arbitrarily set within a range of 1 mm / second or more and 100 mm / second or less, for example.

  By such continuous measurement, the surface roughness of the shape of the lower surface 4 of the piston ring 1 and the surface roughness of the shape of the lower surface 41a of the measuring ring gauge 41 are measured, and the surface roughness data indicates the degree of twist of the piston ring 1. This is basic data for evaluating (for example, the twist angle θ).

  The surface roughness meter 51 operates as follows.

  First, as shown in FIG. 7A, in the standby state before measurement, the surface roughness meter 51 is moved to a predetermined position by the X-direction drive device 62 shown in FIG. 2 and a Y-direction drive device (not shown). ing. The probe 511 of the surface roughness meter 51 is located at a position close to the outer peripheral edge of the measurement ring gauge 41. The position in the standby state is the position of the surface roughness meter 51 in the initial stage or the position immediately after the last measurement is finished. At this time, the probe 511 is not located at the measurement start position, and is further away from the lower surface 41 a of the measurement ring gauge 41. The position of the stylus 511 is set by pushing the auxiliary member 55 operating like a lever at the fulcrum 53 upward by the tip 601 of the cylinder 60 provided on the opposite side with the fulcrum 53 in between.

  Next, as shown in FIG. 7B, the surface roughness meter 51 is moved to a predetermined measurement position. This movement is performed by moving the surface roughness meter 51 in the X1 direction by the X direction driving device 62 shown in FIG. Also at this time, the probe 511 remains separated from the lower surface 41 a of the measurement ring gauge 41.

  Next, as shown in FIG. 7C, the cylinder 60 is operated at the position shown in FIG. 7C to lower the tip 601 and push the auxiliary member 55 on the cylinder 60 side downward. The measuring element 511 provided on the opposite side with the fulcrum 53 in between is pushed upward and set at the measurement start position.

  Next, as shown in FIG. 7D, the surface roughness meter 51 is moved in the X2 direction by the X-direction drive device 62 shown in FIG. 2 at the position of the probe 511 in FIG. 7C (FIG. 8). See), and measure the surface roughness during the movement.

  In the surface roughness meter 51, the position adjusting member 54 is a member that can adjust the position of the auxiliary member 55 in the Y direction, and is a member that adjusts the inclination or level of the auxiliary member 55 when the tip 601 of the cylinder 60 hits. It is. The auxiliary member 55 moves like a lever around a fulcrum 53 provided near the center thereof, and is a member for reflecting the surface roughness data measured by the probe 511 to the Y-direction digital gauge 57 in a sensitive manner. is there. The fine adjustment member 56 is a member to which a force for pulling up the auxiliary member 55 in the Y1 direction is always applied. The balance adjusting member 59 is a member to which a force that pushes down the auxiliary member 55 in the Y2 direction is always applied. Fine adjustment of the surface roughness meter 51 is performed by the fine adjustment member 56 and the balance adjustment member 59. The cylinder 60 may be an air cylinder or a hydraulic cylinder.

  The surface roughness data measured by the surface roughness meter 51 is accurately measured in submicron units by the X direction digital gauge 57 and the Y direction digital gauge 58.

(Calculation process)
The calculation step is a step of calculating the degree of twist of the piston ring 1 by calculating the surface shape data (surface roughness data) obtained in the surface shape measurement step. As the degree of torsion, the torsion angle θ is usually calculated, but the degree of torsion may be evaluated by other amounts, for example, the difference in displacement of measurement points between two or more measurement points. The torsion angle θ is the angle of torsion when the pressure applied from the upper surface 2 and the lower surface 4 of the piston ring 1 is released, and the measurement line L that contacts the lowest point of the lower surface of the piston ring 1; The angle with the lower surface 4 of the piston ring 1. The torsion angle θ varies depending on the specifications of the piston ring 1, but usually an arbitrary width within the range of more than 0 ° and 5 ° or less is set as the quality specification. In addition, it may be paraphrased with more than 0 degree as 1 minute or more.

  To calculate the twist angle θ, first, a plurality of piston rings 1 having different twist angles θ are prepared in advance. Next, the torsion angle θ is compared with the surface roughness data obtained by the surface roughness meter 51 for the piston ring 1 to create a relational expression showing the relationship between the surface roughness data and the torsion angle θ. . Specifically, for example, the X value measured by the X direction digital gauge 58 and the Y value measured by the Y direction digital gauge 57 can be converted into a straight line by the least square method and calculated from the angle of intersection.

  Based on the obtained relational expression, the twist angle θ is calculated from the measured surface roughness data, and the quality control of the obtained piston ring 1 can be performed based on the twist angle θ. If the relationship between the surface roughness data and the torsion angle θ is known, it is not necessary to manage by the torsion angle θ, and the range of the surface roughness data may be defined and managed. In addition, the calculation from the surface roughness data to the twist angle θ may be performed entirely or in any span.

  The calculation is performed by an arithmetic device (not shown), and the result is stored in a storage device or a recording device, displayed on a display device as needed, and monitored, or printed out by a printing device. preferable.

(Discharge process, discharge mechanism)
As shown in FIG. 9, the discharging step is a step of moving the press-fitting member 42 and discharging the measured piston ring 1 from the measuring ring gauge 41. The discharge mechanism 80 that performs this step can be performed by the press-fitting member 42, the base member 45, and the receiving member 81.

  First, as shown in FIG. 9A, the drive device 46 (see FIG. 2) is operated to move the base member 45 to a position below the measurement ring gauge 41 (see FIG. 9B). As shown in FIG. 5A, the amount of movement is preferably returned to a desired position before the base member 45 is raised.

  Next, as shown in FIGS. 9B and 9C, the driving device 43 (see FIG. 2) is operated to push down the press-fitting member 42 from above and push it against the piston ring 1 mounted on the measurement ring gauge 41. The piston ring 1 is pushed in until it falls downward from the measurement ring gauge 41. The piston ring 1 that has fallen is received by a receiving member 81 that is arranged in advance. The receiving member 81 is sent to a guide member 91 constituting an alignment mechanism 90 described later by the operation of a driving device (not shown). The pressing amount (pressing stroke) of the press-fitting member 42 is preferably an amount until the piston ring 1 drops from the measuring ring gauge 41. Specifically, it is preferable to push down until the surface 44 of the press-fitting member 42 is positioned below the lower surface 41a to the extent that it protrudes from the lower surface 41a of the measurement ring gauge 41.

  The shape and form of the receiving member 81 are not particularly limited as long as the receiving member 81 can receive the piston ring 1 dropped from the measuring ring gauge 41. As an example of the shape, a flat receiving plate may be used, a rod-shaped member that can hook a ring portion other than the joint 8 may be used, or a rail-shaped or lattice-shaped member. Also good. In the form shown in FIG. 9, the receiving member 81 enters and exits from the right direction, but the position of the receiving member 81 is not particularly limited, and may be on the near side or the far side.

(Alignment process, alignment mechanism)
As shown in FIG. 10, the alignment step is a step of aligning the direction of the joint 8 of the discharged piston ring 1 after the discharge step. The piston ring 1 in which the direction of the abutment 8 is aligned in this alignment process can be easily supplied to the next process.

  FIG. 10 is an explanatory diagram of the alignment mechanism 90 performed using the guide member 91. The guide member 91 is a rod-shaped core member, and includes a tapered portion 92 having a part in the circumferential direction extending in the longitudinal direction. The taper portion 92 has a shape having two planes on both sides of the ridge-shaped top portion, and the piston ring 1 is aligned so that both ends of the abutment 8 are placed on the left and right planes of the top portion 93. Such a guide member 91 is formed by processing a round bar and providing a tapered portion 92. However, the guide member 91 is not limited to the form shown in FIG. 10, and various forms can be adopted as long as they can be aligned.

  According to the shape measuring method and the shape measuring apparatus 20 described above, it is possible to easily and stably measure the degree of twisting of the piston ring 1 that causes twisting during use.

  That is, the piston ring 1 inserted into the measurement ring gauge 41 is in the same state as the state in which it strikes against the cylinder wall 10 due to the twisting action caused by the inner defect portion 6, so that the shape of the piston ring 1 is changed in this state. By measuring, it is possible to evaluate an appropriate degree of torsion in an actual use state. According to each of the above steps, the piston ring 1 is inserted into the measurement ring gauge 41, and the surface shape of the lower surface 4 of the piston ring 1 and the lower surface 41a of the measurement ring gauge 41 are continuously measured. Since measurement can be performed in comparison with the reference object (measurement ring gauge 41), automation or semi-automation can be realized. As a result, there is no individual difference in measurement, the measurement time can be made constant and shortened, and the repeatability of measurement becomes constant, thereby improving reproducibility. In addition, periodic sampling inspection, 100% inspection, etc. can be arbitrarily selected, and highly reliable shape measurement can be performed. In addition, by collecting the obtained results, highly reliable statistical processing can be realized.

DESCRIPTION OF SYMBOLS 1 Piston ring 2 Outer peripheral sliding surface 3 Upper surface 4 Lower surface 5 Inner peripheral surface 6 Inner defect | deletion part 8 Mouth part 10 Cylinder wall 11 Piston 12 Piston ring groove 13 Piston ring groove lower surface 16 Measuring ring gauge 17 Measuring surface plate 18 Needle touch Surface roughness meter 19 Base member 19a Base member surface θ Twist angle L Measurement line 20 Shape measuring device 30 Conveying mechanism (conveying device)
31 Conveying Member 31a Tip 32 Guide Member 32a Taper 32b Straight Part 33 Conveying Base 40 Insertion Mechanism (Insertion Device)
41 measurement ring gauge 41a measurement ring gauge lower surface 41b measurement ring gauge inner surface 41c measurement ring gauge upper surface 411 taper surface 412 insertion mounting surface 42 press-fitting member 43 press-fitting member drive device 44 press-fitting member surface 45 base member 46 Base member driving device 47 Base member surface 48 Mounting member 49 Notch 50 Surface shape measuring mechanism (surface shape measuring device)
51 Contact Surface Roughness Meter, etc. 511 Measuring Point 53 Support Point 54 Position Adjustment Member 55 Auxiliary Member 56 Fine Adjustment Member 57 Y Direction Digital Gauge 58 X Direction Digital Gauge 59 Balance Adjustment Member 60 Cylinder 601 End of Cylinder 62 X Direction Drive Device 80 Discharge mechanism (discharge device)
81 receiving member 90 alignment mechanism (alignment device)
91 Guide member 92 Tapered part 93 Top part

Claims (6)

Measures the degree of torsion of the piston ring that consists of an outer peripheral sliding surface, an upper surface, a lower surface, and an inner peripheral surface, and has an inner chip that has been machined at the inner end of the upper surface, and becomes circular when the abutment is closed A shape measuring method for
A conveying step of conveying the piston ring to above the measuring ring gauge while gradually closing the joint with the guide member;
An insertion step of inserting the piston ring with the abutment closed into the measurement ring gauge with a press-fitting member;
A surface shape measuring step for continuously measuring the surface shape of the lower surface of the piston ring inserted into the measuring ring gauge and the lower surface of the measuring ring gauge;
And a discharging step of discharging the measured piston ring from the measurement ring gauge by moving the press-fitting member.   The shape measurement of the piston ring according to claim 1, wherein the measurement ring gauge contacts a base member that aligns the lower surface of the measurement ring gauge and the lower surface of the piston ring in the same plane when the piston ring is inserted. Method.   The shape measurement method of the piston ring of Claim 1 or 2 which performs the shape measurement of the said piston ring with a contact-type or non-contact-type surface roughness measuring apparatus.   The shape of the piston ring according to any one of claims 1 to 3, further comprising a calculation step of calculating a torsion angle of the piston ring by calculating data on a change in surface shape obtained in the surface shape measurement step. Measuring method.   The shape measuring method of the piston ring according to any one of claims 1 to 4, further comprising an aligning step of aligning the direction of the exit of the piston ring discharged after the discharging step. Measures the degree of torsion of the piston ring that consists of an outer peripheral sliding surface, an upper surface, a lower surface, and an inner peripheral surface, and has an inner chip that has been machined at the inner end of the upper surface, and becomes circular when the abutment is closed A shape measuring device
A conveyance mechanism that includes a guide member and a conveyance member, and conveys the piston ring to above the measurement ring gauge while gradually closing the joint;
An insertion mechanism that includes a press-fitting member and a base member, and that inserts the piston ring having a closed joint into the measurement ring gauge until it hits the base member;
A surface shape measuring mechanism comprising a surface shape measuring device and continuously measuring the surface shape of the lower surface of the piston ring inserted into the measuring ring gauge and the lower surface of the measuring ring gauge;
An apparatus for measuring the shape of a piston ring, comprising: a discharge mechanism that moves the press-fitting member and discharges the piston ring after measurement from the ring gauge for measurement.

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