JP2005111599A - Method and device for assembling piston ring - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a device and a method for assembling a piston ring by which an extremely thin-walled side rail can be surely cut out one by one. <P>SOLUTION: First of all, one cutting-out claw 81 is advanced and engaged with the side rail 8 of the uppermost stage. Next, a claw member of a pushing-up mechanism, which supports the lower end of the stacked side rails 8, is slightly lowered. Then, a gap is formed between the side rail 8 of the uppermost stage and the side rail 8 beneath it. The other cutting-out claw 82 is advanced while aiming at the gap. The side rail 8 of the uppermost stage is put into a notch 86. In this case, a relatively large gap is formed between the side rail 8 of the uppermost stage and the side rail 8 beneath it. The notch 86 of the cutting-out claw 82 has a larger dimension of the thickness direction than that of a notch 83 of the cutting-out claw 81. Consequently, the side rail 8 can be simply put into the notch 86 even if dimensional deviation occurs to a certain degree. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an apparatus for assembling a piston ring in a ring groove formed on an outer peripheral surface of a piston, and more particularly to an apparatus and a method characterized in assembling side rails.

  16 and 17 are an exploded perspective view and a completed view of a general piston, FIG. 18 is an enlarged cross-sectional view of a main part after the piston ring is mounted, and FIG. 19 is a view as seen from the direction A in FIG. Three ring grooves 2, 3 and 4 are formed on the outer periphery, a top ring 5 is fitted into the ring groove 2 closest to the tip, and a second ring 6 is fitted into the second ring groove 3, First and second side rails 8 and 9 are fitted in the third ring groove 4 with an expander ring 7 interposed therebetween. These top ring, second ring, expander ring, and first and second side rails are collectively referred to as a piston ring in this specification. Each of these rings is a C-ring having a cut, and the top ring 5 and the second ring 6 constitute a compression ring, and the expander ring 7 and the first and second side rails 8 and 9 constitute an oil ring.

  Various methods have been conventionally used to fit the piston ring into the ring groove.

  For example, Patent Document 1 discloses a guide member and a restriction in order to allow the top ring, the second ring, the expander ring, and the first and second side rails to be fitted into the ring groove with one device. A structure using a member is disclosed.

  In particular, regarding the fitting of the expander ring and the first and second side rails, a sleeve and a guide member are provided outside the piston, and one expander ring and the first and second side rails are provided on the outer periphery of the guide member. Then, the restricting member is inserted between the expander ring and the first and second side rails. In this state, the expander ring is lowered until it reaches the position of the ring groove, and the guide member is further lifted. Then, the expander ring is dropped into the ring groove, and then the regulating member is released to the outside and the pressing member is lowered, so that the first and second side rails are sequentially placed in the gap between the expander ring and the ring groove. I try to drop it.

  Further, in Patent Document 2, when the expander ring is fitted into the ring groove, in order to prevent the end portions of the expander ring from overlapping each other, the expander ring is preceded by other parts. The content which inserts the edge part of a cut | interruption part in a ring groove, and inserts the remaining part after that is indicated.

  Further, in Patent Document 3, a small-diameter portion is continuously provided under the stock portion of the cylindrical magazine in order to surely cut out one piston ring held in a stacked state on the outer periphery of the cylindrical magazine. It is disclosed that a piston ring is once dropped into this small diameter portion and only one is separated, and the separated piston ring is further expanded by a lower expanding portion and fitted into a ring groove.

  Further, in Patent Document 4, a part of a spacer (expander ring) fitted in the ring groove is protruded from the ring groove so that the side rail can be smoothly fitted in the ring groove. It is disclosed that a side rail is incorporated into a ring groove using a guide as a guide.

Further, in Patent Document 5, a magazine portion is configured by a plurality of guide rods, a diameter-expanding guide portion is provided at the upper end of the magazine portion, and a pusher member is lifted by a driving portion provided along with the magazine portion. Describes the content of pushing up the piston ring loaded on the outer periphery of the magazine and fitting it into the ring groove of the piston.
Japanese Patent Laid-Open No. 6-8070 [0013] and FIG. Japanese Patent Laid-Open No. 9-253955 JP-A-9-253756 JP 2003-113939 A JP 7-266151 A

  As described above, the problem with the conventional piston ring assembly apparatus is the side rail cutout. That is, the side rails are extremely thin compared to other piston rings, and it is difficult to cut out one by one from the stacked state, and several side rails may be cut out simultaneously.

  Patent Document 1 describes how to cut out the side rail and expander ring after being cut into the groove of the piston, but describes how to cut out the two side rails. However, in Patent Document 1, since two side rails and one expander ring are assembled as a set and assembled, there is a problem in terms of efficiency in assembling continuously.

  In Patent Document 2 and Patent Document 3, a small-diameter portion is provided at a lower portion of a stock portion that holds a large number of piston rings (top ring or second ring) in a stacked state, and piston rings are dropped into the small-diameter portions one by one. However, it is difficult to reliably separate one by one. Especially, the top ring and the second ring are relatively thick and easy to separate, but the side rails are thin, so it is difficult to cut out one by one.

  According to the method disclosed in Patent Document 4, it is easy to insert the cut-out side rail between the expander ring and the groove formed in the piston, but how to cut out the side rail one by one There is no mention about. Patent Document 5 also does not disclose how to cut out the side ring.

  In order to solve the above problems, the piston ring assembling apparatus according to the present invention includes an piston ring assembling line, an expander ring assembling station, a side rail assembling station, a second ring assembling station, and a top. A ring assembly station is provided, and the side rail assembly station includes a magazine portion that holds the side rails in a stacked state, and a pair of cutting claws that cut out the side rails one by one from the magazine portion, One cut-out claw of the pair of cut-out claws engages with the uppermost side rail of the side rails in a stacked state before the other cut-out claw, and the other cut-out claw is one cut-out claw Enter the gap between the uppermost side rail that is held at one end and the lower side rail. It was set as the composition which included.

  In the piston ring assembling apparatus, the pair of cutout claws are formed with notches into which side rails are inserted, and the thickness direction of the cutout formed in the other cutout claw rather than the cutout formed in the one cutout claw When the size of is increased, the side rails can be easily cut out one by one.

  Further, according to the piston ring assembly method of the present invention, when the side rails are cut out one by one from the magazine part that holds the side rails in a stacked state, one of the pair of cutting claws advances toward the magazine part. Engage with the uppermost side rail, and then lower the entire side rail held in a stacked state with the position of one cut-out claw left unchanged, A gap was formed between the rail and the other cut-out claw was advanced and engaged with this gap.

  According to the present invention, the side rails can be reliably cut out one by one from the state in which the thin side rails are stacked. Therefore, it is possible to easily assemble the side rails, which has been the bottleneck for automation in the past.

  Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is an overall plan view of the piston ring assembly apparatus according to the present invention, and FIG. 2 is a front view of the piston ring assembly apparatus.

  The piston ring assembly device is composed of a piston supply line L1, a piston ring assembly line L2, and a piston discharge line L3. These lines L1 to L3 are viewed in a plan view so as to surround an operator's arrangement space. It is arranged in a U shape.

  As shown in FIG. 3, the piston supply line L <b> 1 is provided with a piston loading roller conveyor 11 that is orthogonal to the conveying direction of the conveying belt 10 at the upstream end of the conveying belt 10, and is pressed to a position that does not contact the upper surface of the conveying belt 10. A plate 13 is provided, and the piston 1 conveyed by the conveying belt 10 is pressed against the side wall 12 so as to be aligned in one row.

  Further, an extruding jig 14 is provided at the downstream end of the conveying belt 10, and a positioning mechanism 15 is provided at a position facing the extruding jig 14. The positioning mechanism 15 includes a rotary table 16, a lift unit 17 such as a cylinder unit or a ball screw that lifts and lowers the rotary table 16, a centering device 18 disposed at a position where the rotary table 16 is lowered, and the rotary table 16 is lifted The optical sensor unit 19 is arranged at the position.

  As described above, the pistons 1 placed on the roller conveyor 11 are aligned in a row by the press plate 13 while being conveyed by the conveyor belt 10. Then, the first piston among the pistons aligned in one row is pushed out of the conveyor belt 10 and placed on the pushing jig 14.

  At this time, the conveying belt 10 returns in the reverse direction by about 1 cm, and the pressing plate 13 presses the remaining piston row so that the next piston is not brought into the pushing jig 14 together with the previous piston. The piston placed on the tool 14 is separated from the subsequent piston so that when the pushing jig 14 protrudes in the direction of the positioning mechanism 15, it does not hit the piston remaining on the conveying belt 10.

  The piston cut out from the conveyor belt 10 is pushed out and transferred onto the rotary table 16 located below the positioning mechanism 15 by the pushing jig 14. The hand of the centering device 18 presses against the transferred piston from both sides to perform centering.

  When centering is completed, the rotary table 16 on which the piston is placed rises. An optical sensor unit 19 is fixed to the lower base of the turntable 16. The rotary table rises while rotating and stops at the set position. At this time, the rotation of the turntable 16 stops at a position where the light from the light emitting element 19a passes through the pin hole 1a of the piston and is caught by the light receiving element 19b. This completes the positioning of the piston.

  The piston ring assembly line L2 for assembling the piston ring (top ring, second ring, expander ring, first and second side rails) with respect to the piston 1 that has been positioned will be described below.

  As shown in FIG. 2, the piston ring assembly line L2 includes an expander ring assembly station St1, a first side rail assembly station St2, a second side rail assembly station St3, and a second ring assembly. The station is composed of a station St4 and a top ring assembly station St5. In this embodiment, two expander ring assembly stations St1 are provided side by side.

  Moreover, the piston transfer mechanism 20 is provided along the assembly line L2 of the piston ring. As shown in FIG. 5, the piston transfer mechanism 20 is provided with a horizontal rail 22 on a frame 21, and a traveling body 23 movably engaged with the rail 22. A lifting body 25 is movably engaged with the vertical rail 24, and a finger 26 that can be opened and closed is provided on the lifting body 25.

  Six lifts 25 are arranged at the same intervals as the stations St1 to St5, and the pistons are sequentially fed from the upstream side to the downstream side station (from the right side to the left side in FIG. 2).

  Each of the stations St1 to St5 constituting the piston ring assembly line L2 has the same basic configuration, and the expander ring assembly station St1 includes an overlap prevention mechanism, a first side rail assembly station St2, and The second side rail assembly station St3 is provided with a cutting mechanism.

  The basic configuration of each station will be described with reference to FIGS. 6 and 7 by taking the expander assembling station St1 as an example. Here, FIG. 6 is a side view of the lifting mechanism, and FIG. 7 is a front view of the lifting mechanism.

  The expander ring assembling station St <b> 1 fixes a base 31 to a base 30, a column 32 is erected on the base 31, and a magazine unit 40 is supported on the column 32. The magazine portion 40 is composed of a cup 41 on which the piston 1 is placed and a guide rod 42 on the exterior of the expander ring 7. As shown in FIG. 8, the cup 41 is detachable from a receiving portion 33 provided at the upper end of the column 32. It is said that. The reason why it is detachable is to cope with changes in the piston model.

  On the other hand, the guide rod 42 can also be expanded in the radial direction so as to correspond to the model change. That is, a vertical lifting rod 43 is slidably supported on a support plate 34 fixed to the column 32, and a roller 44 is attached to the lower end of the vertical rod 43. It is in contact with the cam surface of a cam 45 that is rotatably arranged on the base 30 by the resilient force of a spring 49 provided between the rod 43 and the rod 43. Further, cams 46 and 46 are attached to the middle portion of the lifting rod 43 at two upper and lower positions, and a roller 48 provided at one end of the link rod 47 connected to the guide rod 42 is brought into contact with the cam 46. I'm coughing.

  Thus, when the cam 45 is rotated and the raising / lowering rod 43 and the cam 46 ascend accordingly, the link rod 47 in contact with the cam 46 moves outward as shown in FIG. The connecting guide rod 42 is also moved outward, and the diameter of the magazine portion 40 is increased. Similarly, when the cam 45 is further rotated and the elevating rod 43 is lowered, the diameter of the magazine portion 40 is reduced. Thus, the diameter of the magazine portion 40 is rotated by the cam 45 to cope with a change in piston (piston ring) model.

  Returning to FIG. 6, the base 30 is rotatably supported by a frame 50 via a shaft 51. An arm 52 extends from the base 30 to the back side, and an air spring 53 is interposed between the arm 52 and the frame 50.

  The base 30 also supports a push-up mechanism 60. This push-up mechanism 60 has a ball screw 63 that is rotated by a motor 62 in a case 61, and a lifting body 64 is screwed into the ball screw 63, and the lifting body 64 is in a stacked state held by the magazine unit 40. A claw member 65 that pushes up the expander ring 7 (piston ring) from below is provided, and a cylinder unit 66 is provided between the case 61 and the frame 50.

  Thus, when the cylinder unit 66 is extended, the magazine portion 40 and the push-up mechanism 60 are integrally tilted toward the operator with the shaft 51 as the center, as shown in FIG. In this state, a new expander ring 7 (piston ring) is loaded into the magazine section 40. In the illustrated example, the magazine unit 40 and the push-up mechanism 60 are tilted integrally. However, only the magazine unit 40 may be tilted.

  The basic configuration of each of the stations St1 to St5 has been described above, but the expander assembly station St1 includes an expander ring overlap prevention mechanism.

  FIG. 11 is a plan view of the overlap prevention mechanism, FIG. 12 is a side view of the overlap prevention mechanism, and the overlap prevention mechanism 70 is in front of the station St1 and has a height substantially equal to the upper end of the magazine portion, that is, the piston mounting cup. In addition, a U-shaped support plate 71 is provided, and a fan-shaped plate 72 is attached to the support plate 71 so as to be able to advance and retreat toward the piston 1, and a convex portion 73 provided at the front end of the fan-shaped plate 72 is a ring of the piston 1. It enters into the groove 4.

  In the above, when the motor 62 is driven to raise the elevating body 64 (claw member 66) in a state where the front end convex portion 73 of the fan-shaped plate 72 has entered the ring groove 4, as shown in FIG. The expander ring 7 in a stacked state that is packaged on the outer surface of the cup 41 gradually rises while expanding in diameter on the outer periphery of the cup 41, and the uppermost expander ring 7 is detached from the upper end of the cup 41 and fits in the ring groove 4. . At this time, since the convex part 73 has previously entered the part where the cut of the expander ring 7 enters, the part of the cut does not overlap.

  The piston into which the expander ring 7 is fitted is sent to the first side rail assembly station St2 by the transfer mechanism 20, and the first side rail 8 is fitted into the ring groove 4 at this station St2.

  Here, since the side rails 8 and 9 are thinner than the other piston rings, it is difficult to cut out one by one, and two or more of the side rails may be cut out at the same time. It was. Therefore, in the present invention, a unique cutout mechanism is provided.

  FIG. 14 is a plan view of the side rail cutting mechanism, FIGS. 15A to 15C are views for explaining the operation of the side rail cutting mechanism, and the side rail cutting mechanism 80 includes left and right cutting claws 81 and 82. Yes. A cutout 83 into which only one side rail can enter is formed at the tip of one cutout claw 81, and a recess 85 for escaping the side rail positioning bar 84 and the cutout 83 are formed at the tip of the other cutout claw 82. A notch 86 having a large dimension in the thickness direction is formed.

  In the above, in order to cut out one piece of the side rail 8, first, as shown in FIG. 15A, the cutting claw 81 is advanced first and the uppermost side rail 8 is inserted into the notch 83 at the tip.

  The conventional side rail cut-out mechanism is a claw having the same shape on the left and right, and simultaneously cuts out the side rail from the left and right. However, the side rail is a C-ring shape with a slight cut, and there are steps and twists on the left and right of this cut due to processing. It was extremely difficult, and many handling mistakes occurred at this point. However, the side rail can be easily cut into the notch if it is one of the left and right claws.

  Next, the claw member 65 of the push-up mechanism 60 (see FIG. 6) supporting the lower ends of the stacked side rails 8 is slightly lowered, and the other cut-out claw 82 is lowered in synchronization with the lowering of the claw member 65. Then, as shown in FIG.15 (b), a clearance gap is formed between the uppermost side rail 8 and the side rail 8 under it. Instead of lowering the claw member 65 slightly, the other cutout claw 81 may be raised while leaving the other cutout claw 82.

  In the illustrated example, the heights of the cutout claws 81 and 82 are initially equal. However, the cutout claw 81 and the cutout claw 82 may be shifted in height from the beginning.

  If a gap is formed between the uppermost side rail 8 and the lower side rail 8 as described above, the other cut-out claw 82 is advanced toward the gap, and the uppermost stage rail is inserted into the notch 86. The side rail 8 is inserted. In this case, a relatively large gap is formed between the uppermost side rail 8 and the lower side rail 8, and the cutout 86 of the cutout claw 82 is larger than the cutout 83 of the cutout claw 81 as described above. Since the dimension in the thickness direction is large, the side rail 8 can be easily inserted into the notch 86 even if there is some dimensional deviation. Further, since the uppermost side rail 8 and the lower side rail 8 are separated from each other, the two side rails 8 do not enter the notch 86.

  As described above, when the fitting of the side rail 8 is completed, the transfer mechanism 20 sequentially transfers the pistons to the second side rail assembly station St3, the second ring assembly station St4, and the top ring assembly station St5. This completes the mounting of the piston ring. The piston 1 to which all the piston rings are fitted is sent to the payout line L3, and after inspection, defective products are selected and all operations are completed.

  The piston ring assembling apparatus and the assembling method according to the present invention can be applied to a piston of a general-purpose engine in addition to a piston incorporated in an engine of an automobile or a motorcycle.

Overall plan view of piston ring assembly apparatus according to the present invention Front view of the piston ring assembly device Plan view of piston supply station (cut out one by one: once the belt is back) Side view of piston positioning mechanism (pin hole with light emitting element and light receiving element) Side view of transport mechanism Side view of lifting mechanism Front view of lifting mechanism The figure which shows the part of the loading cup of the magazine Explanatory drawing of cam and diameter adjustment of lifting mechanism Side view of tilted lifting mechanism Top view of the expander ring break prevention mechanism Side view of the expander ring break prevention mechanism The figure explaining the operation in which the piston ring (expander ring) fits into the ring groove Plan view of side rail cutting mechanism Illustration explaining the action of the side rail cut-out mechanism (descent of the magazine) The exploded perspective view which shows the state before attaching a piston ring to a piston Piston with piston ring installed Expanded cross-sectional view of the main part of the piston with the piston ring attached The figure seen from the A direction of FIG.

Explanation of symbols

L1 ... Piston supply line L2 ... Piston ring assembly line L3 ... Piston delivery line St1 ... Expander ring assembly station St2 ... First side rail assembly station St3 ... First side rail assembly station St4 ... Second ring assembly station St5 ... Top ring assembly station
DESCRIPTION OF SYMBOLS 1 ... Piston, 1a ... Pin hole, 2, 3, 4 ... Ring groove, 5 ... Top ring, 6 ... Second ring, 7 ... Expander ring, 8 ... First side rail, 9 ... Second side rail, DESCRIPTION OF SYMBOLS 10 ... Conveyance belt, 11 ... Roller conveyor, 12 ... Side wall, 13 ... Holding plate, 14 ... Extruding jig, 15 ... Positioning mechanism, 16 ... Rotary table, 17 ... Lifting mechanism, 18 ... Centering device, 19 ... Optical sensor Unit: 19a ... Light emitting element, 19b ... Light receiving element, 20 ... Piston transfer mechanism, 21 ... Frame, 22 ... Rail, 23 ... Running body, 24 ... Rail, 25 ... Lifting body, 26 ... Finger, 30 ... Base, 31 ... Stand, 32 ... Stand, 33 ... Receiving part, 34 ... Support plate, 40 ... Magazine part, 41 ... Cup, 42 ... Guide rod, 43 ... Elevating rod, 44 ... Roller, 45, 46 ... Cam , 47 ... Link rod, 48 ... Roller, 49 ... Spring, 50 ... Frame, 51 ... Shaft, 52 ... Arm, 53 ... Air spring, 60 ... Push-up mechanism, 61 ... Case, 62 ... Motor, 63 ... Ball screw, 64 ... Lifting body, 65 ... claw member, 66 ... cylinder unit, 70 ... overlap prevention mechanism, 71 ... support plate, 72 ... fan-shaped plate, 73 ... convex part, 80 ... side rail cut-out mechanism, 81, 82 ... left and right cut-out claws 83, 86 ... Notches, 84 ... Side rail positioning bars, 85 ... Recesses.

Claims (3)

A piston ring assembly device for fitting a piston ring into a ring groove of a piston. The piston ring assembly device includes an expander ring assembly station, a side rail assembly station, and a second ring assembly station. And an assembly station of the top ring, the assembly station of the side rail is provided with a magazine part for holding the side rails in a stacked state, and a pair of cutting claws for cutting out the side rails one by one from the magazine part, One cut-out claw of the pair of cut-out claws engages with the uppermost side rail of the side rails in a stacked state before the other cut-out claw, and the other cut-out claw is one cut-out claw The uppermost side rail that is held at one end by the lower side rail Piston ring assembly device characterized in that it enters the gap between 2. The piston ring assembling apparatus according to claim 1, wherein the pair of cutout claws are formed with notches into which side rails are inserted, and the cutouts formed on the other cutout claws are formed on the other cutout claws. The piston ring assembling apparatus characterized in that the dimension of the direction of the thickness is larger. A method of assembling a piston ring in which the piston ring is fitted into the ring groove of the piston, and a pair of cutting claws is used to cut out the side rails one by one from the magazine portion that holds the side rails constituting the piston ring in a stacked state. One of the two moves forward toward the magazine and engages with the uppermost side rail, and then the entire side rail that is held in a stacked state is relatively lowered with the position of one cut-out claw left unchanged. A method for assembling the piston ring, wherein a gap is formed between the uppermost side rail and the lower side rail, and the other cut-out claw is advanced and engaged with the gap.