JPH06277957A - Piston ring installing method and device - Google Patents

Abstract

PURPOSE:To specify and take out piston rings efficiently by taking out a large number of piston rings guided by a guiding rod only by opening and closing a freeing hand and a stopping hand. CONSTITUTION:Piston rings R supplied by being arranged coaxially in a large number are arranged vertically by a guiding rod 30, and are put in a condition of dropping by the gravity, and are held by a stopping hand 47. A freeing hand 46 is arranged just above the stopping hand 47, and restrains the piston ring R in the second from below, and locks once so that a large number of piston rings R do not drop. When the stopping hand 47 is released in this condition, only the lowermost end piston ring R supported with it is released so as to be able to drop. Even when the lowermost end piston ring R cannot drop since it is stuck fast on the piston ring situated above by one due to lubricating oil or the like, since fluid is injected to the lowermost piston ring R from above by a fluid nozzle 48, it can be separated by the pressure, and can drop.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates to a method and apparatus for automatically mounting a piston ring on a piston of an internal combustion engine.

[0002]

2. Description of the Related Art Conventionally, in a factory for mass-producing internal combustion engines, the process of mounting a piston ring on a piston has been mostly automated. As means for that purpose, for example, as disclosed in Japanese Patent Laid-Open No. 2-88123, a large-diameter portion having substantially the same diameter as the piston is provided, and the large-diameter portion,
Prepare a guide rod that smoothly connects the smaller diameter part with a tapered part, and fit a number of piston rings concentrically on the guide rod, and then sequentially increase the size of each piston ring one by one. While being moved to the diametrical part, the inner diameter of the taper part is enlarged to a diameter slightly larger than the outer diameter of the piston, guided to the ring groove provided in the piston, and dropped there.

[0003]

Therefore, when it takes a long time in units of hours to move the piston ring from the small diameter portion to the large diameter portion, for example, the work of the previous day is completed and the next day or If the machine is stopped until the number of days further decreases, permanent deformation occurs due to creep on the piston ring that is fitted in the large diameter part or tapered part and stopped in the expanded state, that is, The inner diameter increases substantially, the sealing force exerted on the inner wall of the cylinder and the bottom of the ring groove of the piston changes, and the sealing function is significantly reduced, causing a problem that a large amount of blow-by gas is generated during engine operation. Sometimes.

Furthermore, when the piston rings are axially moved by the axial guide rod and then separated one by one, it is difficult for the adjacent piston rings to be separated by oil or the like attached between them. May be.

[0005]

A method for solving the above-mentioned problems is to remove the piston rings one by one from a guide rod that coaxially supports a large number of piston rings, and take out the piston rings by a transfer means. Is moved to a position substantially coaxial with the piston, the inner diameter of the piston ring is expanded to a diameter larger than the outer diameter of the piston by the diameter expanding means, and then it is moved to the required ring groove formed in the piston, and on the ring groove It is to remove the expanding means from the piston ring.

Further, the device for solving the problem is provided with a guide rod for coaxially supporting a large number of piston rings, and is continuously dropped from the guide rod in the vicinity of the lower end portion of the guide rod. A stop hand for supporting the lowermost end of the piston ring, a relief hand for temporarily locking the ring one level above the lowermost end, and a gas flow from above for the piston ring at the lowermost end. And a fluid nozzle.

[0007]

In the invention of the above method, the piston rings are coaxially arranged and transported in the same manner as in the prior art, and set in the assembly machine. One of them is taken out, the inner diameter is enlarged by the diameter expanding means, and immediately, it is moved to the outside of the desired ring groove to extract the diameter expanding means and fit it into the ring groove. That is, the piston rings are taken out one by one, and are fitted into the pistons each time, and there is no piston ring to be placed in the middle of the assembling.

According to the invention of the above apparatus, a large number of piston rings, which are coaxially arranged and supplied, are arranged vertically by a guide rod, placed in a state of falling by gravity, and held by a stop hand. An escape hand is arranged immediately above the stop hand, and holds down the second piston ring from the bottom so as to temporarily stop the drop of the large number of piston rings. When the stop hand is opened in this state, only the piston ring at the lowermost end supported by the stop hand is opened so that it can fall. Even if the piston ring at the lowermost end adheres to the piston ring one above due to lubricating oil or the like and does not fall, fluid is jetted from above by the fluid nozzle to the piston ring at the lowermost end and peels off due to the pressure. Will be dropped.

[0009]

The present invention will be described below with reference to the illustrated embodiments. In the figure, 10 is a piston ring mounting device according to the present invention, which automatically mounts a piston ring R in a ring groove of a piston P. The mounting device 10 is composed of a large base plate 11 and various devices installed thereon. 12 is a pallet 1 provided on one side of the base plate 11
3 is a support base. A large number of pallets 13 carried by a self-propelled transfer robot 14 are stacked on the support 12. The pallet 13 contains a large number of pistons P to which piston rings R are to be attached. In this description, the piston ring R includes a pressure ring fitted in the upper ring groove of the piston P and an oil ring fitted in the lower ring groove,
In particular, the oil ring includes a combination ring consisting of upper and lower side plates and an expander sandwiched between them.

Reference numeral 15 denotes an articulated transfer robot installed on the loading side of the base plate 11, which takes out the pistons P transferred by the pallet 13 one by one and places them on the transfer tool 16 of the pistons P. The transfer tool 16 moves the piston P between five assembly units 20 described later. Reference numeral 17 denotes a carry-out side transfer robot, which has the same shape as the articulated transfer robot 15 installed at the loading side and is installed at a symmetrical position. Five units of an assembling unit 20 for assembling the piston ring R to the piston P are connected to each other by the machine frame 31 between the loading-side transfer robot 15 and the unloading-side transfer robot 17, and a set of these five units is connected. The mounting unit 20 constitutes one mounting device 10.

Assembling unit 20, as shown in FIG.
Guide rod 3 for supplying a single piston ring R
0, individual separating means 40 for separating and taking out one by one from a large number of piston ring R groups supported by the guide rod 30, and the separated piston ring R
And a fitting means 60 for fitting the piston ring R transferred by the transfer means 50 into a required ring groove formed in the piston P.

The main part of the guide rod 30 is a smooth hollow cylinder having a diameter slightly smaller than the inner diameter of the piston ring R, and the guide rod 30 is mounted on the upper end of the cylinder of the unit 20. A removable fastener 32 for attachment to 31 is provided. 33 is a piston ring R detachably attached to the lower end of the guide rod 30.
Is a retaining pin for supporting the piston ring R fitted to the guide rod 30 so as not to fall out. Therefore, if the retaining pin 33 is removed after the guide rod 30 is attached to the machine frame 31 at the upper end thereof,
The lower end portion of the guide rod 30 is opened, and the individual separating means 40 described later can be operated to pull out the piston rings R one by one.

In the individual separating means 40 of the piston ring,
As shown in FIG. 4, a grip means including an escape hand 46 and a stop hand 47 arranged above and below the guide rod 30 and a plurality of fluids communicating with an air compressor (not shown) as a pressure source. A nozzle 48 is included. The gripping means forming the individual separating means 40 is shown in FIG.
As shown in FIG. 2, it is composed of two gripping hands 42, 42 and an electromagnetic opening / closing driver 44 for opening and closing them, and the opening / closing driver 44 grips in accordance with an order preset by a controller (not shown). The hand 42 is opened and closed. The figure (a) shows the state where the grippers 42, 42 are open, and (b) shows the closed state, respectively. 42a is the gripping hand 4
It is a stop member attached to Nos. 2 and 42, and is for increasing friction so that the outer circumference of the piston ring R is gripped without slipping. The fluid nozzle 48 is 2.5 Kg / cm ²
Is connected to a pressure source (not shown) for supplying the pressure air of 2 mm, and has an inner diameter of 2 mm, and is directed to the piston ring R at the lowermost end supported on the upper surface of the stop hand 47 from a distance of about 2 cm. ing. In this embodiment, the fluid nozzles 48 are provided equidistantly at three locations on the circumference of the piston ring R, and the fluid ejected from the fluid nozzles 48 is air. Further, when the piston ring R is a combination ring, the ejection direction of the fluid nozzle 48 is directed to the concave portion of the expander bent in a wave shape, thereby avoiding a step difference due to deformation.

Next, the operation of the grip means will be described with reference to FIG. First, when the lower stop hand 47 is closed and the retaining pin 33 is removed, a large number of piston rings R are supported on the upper surface of the stop hand 47 as shown in FIG. Has been done. Next, as shown in FIG. 2B, the upper escape hand 46 is closed to grip the second piston ring R from the bottom, and subsequently the lower stop hand 47 is opened. At this time, the lowermost piston ring R is allowed to drop downward due to gravity, but in general, the piston ring R adheres to the adjacent upper piston ring R due to the adhesive force of the rust preventive oil applied at the time of shipment from the factory. In addition, the guide rod 30 and a guide ring 56 described later
It usually does not fall immediately due to the frictional resistance existing between the and. Therefore, by blowing a high-pressure gas from the fluid nozzle 48 onto the upper surface of the piston ring R, the high-pressure gas drops downward and escapes from the guide rod 30, as shown in FIG.

Immediately below the guide rod 30, a transfer plate 51 which constitutes the transfer means 50 is provided. As shown in FIG. 7, the transfer plate 51 has a piston ring R mounted thereon, and a fluid cylinder 52 reciprocates between a position immediately below the guide rod 30 and the individual separating means 40 and a position directly above the piston P. As is clear from FIG. 8, the transfer plate 51 is provided with a three-pronged elevating plate 53 which can be moved up and down at a position immediately below the guide rod 30 in the retracted position. Therefore, when the stop hand 47 is opened, the piston ring R has an inner diameter by the guide rod 30, an outer diameter by the annular guide ring 56, and a rotation stop plate (not shown) provided on the guide rod 30. Is accurately centered by the rotation stopper plate, and the lifting plate 5 is moved by the pressure air ejected from the fluid nozzle 48 so that the ring abutment faces the predetermined direction by the rotation stopper plate.
3 Dropped and supported. The elevating plate 53 is stopped by the locking pin 54, and is moved up and down by a small distance on the transfer plate 51 by an electromagnetic actuator 55.
The operation will be described later. A proximity sensor 58 is adjustably fixed to the end of the machine frame 31, and the proximity sensor 58 detects whether or not the piston P is set at a predetermined position.

In FIG. 9, reference numeral 60 denotes a fitting means for fitting the piston ring R to the piston P. The fitting means 60 is an elevating means 61 that moves up and down on the axis of the piston P,
A diameter expanding means 70 that is supported by the elevating means 61 and moves up and down is included. The elevating means 61 includes two support rods 64, 64 slidably supported by a frame 62 via a bush 63.
And a support plate 66 attached to the lower end thereof, and the support rod 64 is moved up and down by a pneumatic cylinder (not shown) attached to the upper end.

The diameter expanding means 70 is an outer cylinder 71 bolted to the lower surface of the support plate 66, and an inner cylinder 7 that is supported on the inner surface thereof so as to be able to move up and down and is normally elastically urged downward by a spring 73.
2 and. Reference numeral 76 is a spacer for adjusting the size of the space 79 left on the upper surface thereof.

At the lower end of the inner cylinder 72, a cylindrical support claw 80 for supporting the inner diameter portion of the piston ring R and a central protrusion 74 located at the center thereof are formed. Support claw 80
Consists of three thin arc-shaped pieces divided by slits, and these three pieces form one circumferential surface 84 as a whole. The diameter of the circumferential surface 84 is the piston ring R
It is set to be almost the same as the inner diameter of, and can be expanded by a small amount. That is, the support claw 80 is urged to be expanded in the outer peripheral direction by the three pressing elements 75, 75, and the expansion in the outer peripheral direction is restricted by the guide ring 77 provided on the outer cylinder 71. To be done. As a result, the maximum diameter of the circumferential surface 84 is restricted by the guide ring 77, and the minimum diameter is restricted by the three pushers 75.

Thus, when the transfer plate 51 advances above the piston P, the lift plate 53 moves to the electromagnetic actuator 55.
Then, the piston ring R supported by it is lifted up and down by a short distance to lift it just below the support claw 80. At this time, the circumferential surface 84 of the support claw 80 is contracted, and the piston ring R is fitted into the outer periphery of the piston ring R. At the same time, the circumferential surface 84 of the support claw 80 is expanded by the pressing element 75 to expand the piston ring R and hold it in that state.

Next, when the transfer plate 51 retracts, the support plate 6
6 starts descending toward the piston P. Central protrusion 74
When the piston contacts the top of the piston P, the inner cylinder 72 is prevented from further descending, so that even if the outer cylinder 71 continues to descend, the spring 73 is compressed and stays at that position. Therefore,
The guide ring 77 forming the lower end portion of the outer cylinder 71 has a piston ring R.
Is pushed downward and pushed out from the end of the support claw 80. Therefore, the piston ring R is dropped onto the ring groove to be fitted. That is, the central protrusion 74 can set a ring groove into which the piston ring R is fitted.

Reference numeral 90 is an inspection device. The inspection device 90 inspects whether the piston ring R is fitted in the ring groove of the piston P at a predetermined position or in a correct posture. That is, the light emitted from the light source 91 is received by the camera 92, the image projected on the camera 92 is processed, and the fitting posture of the piston ring R and its pass / fail judgment are displayed on the display 93. Although this inspection device is not publicly known, many devices of the same type are arranged on an assembly line for mass production improvement.

[0022]

As described above, according to the method invention, the plurality of piston rings R are coaxially supported and supplied, but are separated one by one and supplied to the ring groove of the piston. It Further, since the diameter is expanded immediately before fitting into the ring groove, creep strain does not occur in the piston ring itself. Further, according to the device invention, it is possible to specify one piston ring to be taken out only by opening and closing the escape hand 46 and the stop hand 47, and to make the number of piston rings guided by the guide rod small and ejecting from the fluid nozzle. There is an effect that the fluid can be surely separated and supplied by the fast fluid.

[Brief description of drawings]

FIG. 1 is a plan view showing an apparatus for carrying out an assembling method of the present invention.

FIG. 2 is a front view thereof.

FIG. 3 is a side view thereof.

FIG. 4 is a IV-IV sectional view thereof.

FIG. 5 is a VV sectional view thereof.

6 is an operation process diagram shown by a VI-VI cross section in FIG. 4;

7 is a sectional view taken along line VII-VII in FIG.

FIG. 8 is a view on arrow VIII.

9 is an enlarged view of a main part showing a IX-IX cross section in FIG. 1. FIG.

[Explanation of symbols]

 10 ... ・ Mounting device for piston ring R 20 ... Assembly unit 30 ... Guide rod 40 ... Individual separation means 44 ... Opening / closing driver 46 ... Relief hand 47・ ・ ・ Stopping hand 48 ・ ・ ・ Fluid nozzle 50 ・ ・ ・ Transfer means 51 ・ ・ ・ ・ Transfer plate 53 ・ ・ ・ ・ Elevating plate 56 ・ ・ ・ Guide ring 60 ・ ・ ・ Fitting means 61・ ・ ・ Elevating means 66 ・ ・ ・ ・ Support plate 70 ・ ・ ・ ・ ・ ・ Diameter expanding means 71 ・ ・ ・ ・ Outer cylinder 72 ・ ・ ・ ・ Inner cylinder 80 ・ ・ ・ ・ ・ ・ Supporting claw 84 ・ ・ ・ ・ ・ ・ Circumferential surface

Claims (2)

[Claims] 1. A piston rod is separated and taken out one by one from a guide rod that coaxially supports a large number of piston rings, the transfer means transfers the piston rings to a position substantially coaxial with the piston, and the expansion means expands the diameter. A method for mounting a piston ring in which the inner diameter of the piston ring is enlarged to a diameter larger than the outer diameter of the piston, and then the ring is moved to a required ring groove formed in the piston, and the diameter expanding means is removed from the piston ring on the ring groove. 2. A guide rod for coaxially supporting a large number of piston rings, and for supporting a lowermost end of a piston ring which is adjacent to a lower end portion of the guide rod and continuously drops from the guide rod. Piston ring provided with a stop hand, an escape hand for temporarily locking a ring above the lowermost end, and a fluid nozzle for applying a gas flow from above toward the piston ring at the lowermost end. Mounting device.