JPS6057976B2 - Automatic piston assembly device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an automatic piston assembling device that automatically assembles a piston into a cylinder bore of a cylinder block of an engine.

In the automatic piston assembly device described above, in order to transport the piston with the connecting rod connected to the piston assembly device, it is difficult to assemble the piston and the connecting rod, even when viewed from the piston's transportation posture. After that, before inserting into the cylinder bore, in order to effectively clean and dry the inner surface of the piston, place the piston with the top side up and the skirt part down on a pallet, and then install the connecting rod. It is desirable to transport the equipment in a suspended state. On the other hand, as part of the process of assembling the piston to the cylinder bore, it is necessary to assemble the connecting rod cap to the connecting cup in order to integrate the connecting rod and the crankshaft.

To achieve this purpose, the cylinder block should be transported in a vertical position so that the oil pan mounting surface of the cylinder block is vertical, and the tool for assembling the cap approaches the large end of the connecting rod inside the cylinder block. It is necessary to transport it in a way that is easy to transport. Therefore, the center axis of the cylinder bore of the cylinder block is horizontal, and the direction is different by 90 degrees from the center axis of the piston to be assembled.

The present invention provides a column that is installed upright at a piston assembly position.
The swivel head is supported on a shaft so that it can be rotated and indexed in the vertical plane.
An insertion head is provided on the swivel head so as to be able to slide back and forth,
By arranging a plurality of piston holding cylinders into which pistons can be inserted at the pitch of the cylinder bore at the tip of the insertion head, and providing a piston push rod in the insertion head so as to be able to reciprocate in parallel to the central axis of the piston holding cylinder. , the swivel head is indexed so that the central axis of the piston holding cylinder is vertical, and the piston is held in the piston holding cylinder, and then the swivel head is indexed so that the central axis of the piston holding cylinder is horizontal. Another object of the present invention is to provide an automatic piston assembling device in which the piston of the piston holding cylinder is pushed into and inserted into the cylinder bore by the piston push rod. DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an automatic piston assembly apparatus of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is an overall front view of the automatic piston assembly apparatus of the present invention, FIG. 2 is a plan view thereof, and FIG. 3 is a right side view thereof. A bed 2 is provided on the right side of the cylinder transport conveyor 1, which carries cylinder blocks S on a pallet Pa with the oil pan mounting surface SO vertically erected and sequentially transports them to an assembly station. Column 3 is erected. A swivel head 4 is supported on the front surface 3A of the column 3 so as to be pivotable and indexable in a vertical plane.
On the front of the swivel head 4, there are two guide bars 5A,
5B, the insertion head 6 is guided by guide bars 5A, 5B so as to be slidable in a direction parallel to the pivot plane of the swivel head 4. A cylinder 7 is attached to the side surface of the swivel head 4, and the tip of its piston rod 7A is fixed to the insertion head 6.
Due to the operation of cylinder 7. The insertion head 6 is slid back and forth.

A pinion 9 is keyed to the pivot axis 8 of the swivel head 4. Further, a rack 11 that is reciprocated up and down by a cylinder 10 attached to the upper surface 3B of the column 3 engages with the pinion 9, and the reciprocating movement of the rack 11 causes the swivel head 4 to rotate at 90 degrees. Rotate within range. Accurate positioning of the rotation angle is
This is done by bringing the abutment plate 12 attached to the rear end of the pivot shaft 8 into contact with the stopper 13A or 13B attached to the rear surface 3C of the column 3. Further, an abutment plate 14 is attached to the rear surface of the insertion head 6, a stopper 15 is attached to the front surface of the swivel head 4, and the abutment plate 14 is brought into contact with the stopper 15 at the forward end of the insertion head 6. The forward end position of the insertion head 6 is accurately positioned. A piston carry-in conveyor 16 is provided in a direction perpendicular to the conveyance direction of the cylinder conveyor 1, and the left end of the piston carry-in conveyor 16 is joined to the right side surface 2A of the bed 2.

The piston carrying conveyor 16 places four pistons P corresponding to the bore diameter of the cylinder (however, this varies depending on the number of cylinders in the engine) on a pallet Pb.
It is carried directly under the insertion head 6. Further, a pallet carry-out conveyor 17 is installed in parallel with the piston carry-in conveyor 16, and carries empty pallets P, which have been assembled, to the outside. Piston P is connecting rod C.
The piston P and connecting rod C are transported in a connected state by a pin, but before being assembled to the cylinder block S, the connected piston P and connecting rod C are cleaned and dried. In order to effectively perform this cleaning (particularly the inner surface of the piston P) and drying, in the present invention, the piston P is placed on the pallet Pb with its top surface facing up and the skirt portion of the piston P covered. . That is, as shown in detail in FIGS. 4 and 6, the pallet P used in the present invention is:
It has a convex cross section, and four sets of four protrusions 18A, 18B, 18C, and 18D that fit into the inner circumferential surface of the piston P are provided on the upper surface thereof at equal intervals. In addition, the protrusions 18A and 1
Between 8D and 18B and 18C are grooves 19A and 19B for passing the large end of connecting rod C.
is formed. The bottom surface of the pallet Pb is hollowed out to facilitate cleaning and discharge of cleaning liquid from below. The piston carrying-in conveyor 16 described above is provided with a separator 20 for separating the pallets P conveyed on the conveyor 16 one by one and sending them to the insertion head 6 side.

The separator 20 is rotatably supported in a horizontal plane about a shaft 21, and has claws 23A and 23B at both ends that engage hook grooves 22 formed on the lower side of the pallet Pb. , this separator is driven by an actuator (not shown). In the state shown in FIG. 2, the claw 23A engages with the hooking groove 22 of the leading pallet P, -2, and prevents the leading pallet Pb- and the following pallets P, -3 from being carried in. Note that since the conveyor 16 is constantly driven, a gap occurs between the pallets Pb-2, Pb-3 and the conveyor 16. The previously carried pallet Pb-1 is conveyed by the piston carrying-in conveyor 16 to the left end of the piston carrying-in conveyor 16 shown in the figure. 2
6, it is carried directly under the insertion head 6. The pawl 26 is swung by a cylinder 27, swung downward and engaged with the hooking groove 22 of pallet P1, and swung upward and removed from the hooking groove 22.As will be described later, the pallet Pb −
When the first piston P is transferred to the insertion head 6, the empty pallet Pb-1 is returned to the left end of the piston carry-in conveyor 16 by the claw 26, and the claw 26 swings upward to remove it from the hooking groove 22. It comes off.

A cylinder 28 is provided at the left end of the piston carry-in conveyor 16 in a direction perpendicular to the conveyance direction of the piston carry-in conveyor 16. 1), the empty pallet P,-1 is transferred onto the pallet delivery conveyor 17 shown by the two-dot chain line. When the empty pallet Pb-1 is transferred to the pallet unloading conveyor 17, the separator 20 swings clockwise and one claw 23A moves the pallet P, -
At the same time, the other claw 23B engages with the hooking groove 22 of pallet P, -3. Therefore, the pallet P,-2 is transported by the piston delivery conveyor 16.
The piston is conveyed to the left end of the conveyor 16, and is conveyed directly below the insertion head 6 by the same operation as described above. Next, the separator 20 swings counterclockwise, and the claw 2
When 3B separates from the hooking groove 22 of pallet Pb-3,
Pallet Pb is moved by the movement of the piston carry-in conveyor 16.
-3 moves forward, and the hooking groove 22 of the pallet P5-3 engages with the front pawl 23A and stops, preparing for the next carrying-in operation. When the pallet Pb is carried directly under the insertion head 6 by the claw 26 that is reciprocated by the cylinder 24, a flange formed to protrude below the side surface of the pallet P, as shown in FIG. 29A and 29B are bed 2
It enters the lower surfaces of presser plates 30A and 30B attached to the upper surface in parallel to the conveyance direction of the piston carry-in conveyor 16.

A cylinder base 31 having a concave cross section is attached to the lower surface of the holding plates 30A, 30B, and the flanges 29A, 29B of the pallet Pb are sandwiched between the upper surface of the cylinder base 31 and the holding plates 30A, 30B. On the lower surface of the cylinder base 31, there are four cylinders 32A to 32D (Fig. 1) arranged at the same intervals as the pallet P and the pistons P above.
is installed.

Piston rods 33A to 3 of each cylinder 32A to 32D
At the upper end of 3D are push plates 34A to 34D with semicircular cross sections.
is installed, and the piston rods 33A to 33D
As the connecting rod C rises, it comes into contact with a bearing formed at the large end of the connecting rod C and pushes the connecting rod C upward. As shown in FIGS. 4 and 5, a pallet Pb carried directly under the insertion head 6 is placed on the upper surface of the bed 2.
A piston ring compression device 35 is attached that compresses the piston ring P fitted into the piston P by sandwiching the upper piston P therebetween. That is, a cylinder base 36 is attached to the upper surface of the bed 2, and a cylinder 37 is attached to the cylinder base 36. Further, a cylinder 38 having a smaller diameter than the cylinder 37 is attached to the lower front surface of the column 3 so as to face the cylinder 37 . At the tips of the piston rods 37A and 38A of the cylinders 37 and 38, there are wide plates 39 and 40.
are screwed together. Pressing pads 41JA to 41D and 42A to 42D, whose tips are shaved off into semicircular shapes, are attached to the plates 39 and 40 so as to face each other at the same spacing as the piston P. In addition, two guide bushes 4 are provided at the lower front of the cylinder base 36 and the column 3.
3A, 43B and 44A, 44B are attached facing each other. The guide j bush 43 is attached to the plates 39 and 40.
Guide bars 45A, 45B, 46A and 46B are attached to the guide bars 45A, 45B, 46A and 46B which fit into and slide on the guide bars A, 43B, 44A and 44B. The ends of the guide bars 45A, 45B have large diameter portions 4.
7A, 47B are formed, and the guide bush 43A
, 43) By hitting the end face of B, the pressing pad 4
To accurately locate the stop positions of 1A to 41D. That is, as described above, since the cylinder 37 has a larger pressure receiving area than the cylinder 38, the plate 39 moves forward until the large diameter portions 47A, 74B abut against the guide bushes 43A, 43B, and the pressing pads 42A to 42D of the plate 40 move forward. Insert the piston P between the pressing pads 41A to 41D of the plate 39,
While compressing the piston ring P, the center of the piston P is made to coincide with the center of the piston holding cylinder of the insertion head 6, which will be described later. In this way, the piston ring compression device 35
The piston ring Pr is compressed by the piston ring Pr, and the cylinders 32A to 32D for pushing up are operated to push up the piston P and insert the piston P into the piston holding cylinder.
The detailed structure of the insertion head 6 shown in FIGS. 7, 8, and 10 will be explained.

Four cylindrical piston holding tubes 49A to 49D are inserted into the cavity 48 formed on the front side of the insertion head 6 at the same intervals as the pistons P on the pallet Pb. Flanges 50A to 50D and 51A to 51D are welded to the upper and lower outer peripheral surfaces of the piston holding cylinders 49A to 49D.
On the front surface 6A of the insertion head 6, there are piston holding cylinders 49A to 49A.
Plates 52A and 52B extending left and right are inserted above and below 49D, and the ribs 50A to 50D and 51A to 51D are
It is sandwiched between plates 53A and 53B from the front side.
Vertically elongated spacers 54A, 54B (FIG. 8) are interposed between the plates 52A, 53A and 52B, 53B, and are integrally tightened with bolts. Brim 50
Between A~50D and the plates 52A, 53A, and the brim 51A~
Balls 56 each held by a retainer 55 are inserted between 51D and the plates 52B and 53B.

Therefore, the piston holding cylinders 49Aj to 49D are connected to the plate 52A.
, 53A and 52B, 53B, in a plane perpendicular to the central axis of the piston holding cylinders 49A to 49D,
Can float easily. Brim 50A-50D and 5
A through hole 57 is bored in each of the piston holding cylinders 49A to 49D in parallel to the center axis of the piston holding cylinders 49A to 49D. A bush 58 is fitted into the through hole 57, and the bush 5
8, the plates 52A, 53A, and 52 are connected by a spring 59.
Balls 60A and 60B are inserted to be pressed against B and 53B. Conical holes 61A, 61B into which the balls 60A, 60B fit are formed on the inner surfaces of the plates 52A, 53A and 52B, 53B. Therefore, the central axes of the piston holding cylinders 49A to 49D are held at the required center position of the cylinder bore Sb by the cooperation of the balls 60A, 60B and the conical holes 61A, 61B. The intermediate partition wall 6B of the insertion head 6 has piston holding cylinders 49A to 49A.
Cylinders 62A to 62D are attached on the same center line as 49D.

The cylinders 62A to 62D have pistons 63A to 63D.
is slidably inserted into the pistons 63A to 63D,
Hollow piston rods 64A to 64D are formed at the front and rear. In the hollow parts of the piston rods 64A to 64D,
Push rods 65A to 65D are inserted. Push rod 65A
Disk-shaped push plates 67A to 67D and 68A to 68D are attached to the tips of 65D with a thrust bearing 66 in between. Front push plates 68A to 68D and push rods 65A to 65D in direct contact with the top surface of the piston P
Since elastic bodies (such as rubber) 69A to 69D are inserted between them, if the center of the cylinder bore S does not coincide with the center of the piston holding cylinders 49A to 49D, the cylinder bore will be removed when the piston P is inserted. The push plates 68A to 68D can easily move and align the center of the piston P with the center of the piston S, and the insertion operation of the piston P can be performed smoothly. At the rear of the hollow piston rods 64A to 64D,
Brackets 70A-70D are welded.

In addition, as shown in FIGS. 7 and 10, the insertion head 6
Between the support stands 71A to 71D attached to the bottom surface 6C of the insertion head 6 and the rear wall 6D of the insertion head 6, cylinders 62A to
Guide bars 72A to 72D are attached parallel to 2D, and through holes 7 are bored in the brackets 70A to 70D.
3A to 73D are fitted into the guide bars 72A to 72D, and the brackets 70A to 70D and the piston rod 64A
~64D is prevented from rotating. piston rod 6
Flanges 74A to 74 formed at the front ends of 4A to 64D
A spring 75 is installed between D and the rear push plates 67A to 67D.
A to 75D are inserted, and the push plates 67A to 67D, 68
A to 68D and push rods 65A to 65D are always urged forward with respect to piston rods 64A to 64D.

Blocks 76A to 76 are provided at the rear of the push rods 65A to 65D.
D is pinned, and the blocks 76A to 76D are fitted into the long grooves 77A to 77D formed in the brackets 70A to 70D, and the push rods 65A to 65D and blocks 76A to 7 are
6D is stopped from rotating. As mentioned above, the spring 75A
Since the push rods 65A to 65D are urged forward by the push rods 65A to 65D, the blocks 76A) and 76D are stopped against the rear end surfaces of the piston rods 64A to 64D.

Bolts 78A to 78D are screwed into blocks 76A to 76D, and limit switches 79A to 79D attached to brackets 70A to 70D are connected to bolts 78A to 78D.
The tip of 8D is always pressed. Piston 63A-63D
When the piston P moves forward and is pushed into the cylinder bore Sb by the push plates 68A to 68D, there is no problem if it is pushed in smoothly, but if the piston P gets caught while being pushed, the piston rods 64A to 64D 64D and push rod 65
Relative movement occurs between A and 65D.

In other words, only the piston rods 64A to 64D are connected to the spring 75A.
~75D, and the tips of the bolts 78A~78D separate from the limit switches 79A~79D, detecting a pushing abnormality, stopping the supply of pressure oil to the cylinders 62A~62D, and at the same time turning on warning lamps, etc. This will notify the operator of the abnormality. Dogs D-1 and D-2 are attached to the rear ends of the push rods 65A to 65D, and by stepping on limit switches 80A to 80D and 81A to 81D, the forward and backward ends of the pistons 63A to 63D are detected. , confirmation that the piston P has been pushed in, and the push plate 68A.
~ Confirm the completion of retreat at 68D.

As mentioned above, the cylinder block S is placed on the pallet Pa and transported on the cylinder transport conveyor 1, and when it is transported to a position facing the insertion head 6, the cylinder block
2 rises, lifts up the cylinder block S together with the pallet Pa, and holds the cylinder block S between it and the gate-shaped fixture 83.
Position and fix. In order to smoothly and continuously perform the piston insertion operation performed in the present invention and the subsequent connecting rod cap assembly operation, the cylinder block S has a cylinder head mounting surface Sh.
It is placed on a pallet Pa in an upright state and transported.
As shown in FIGS. 1 and 2, a bed 84 is provided on the left side of the cylinder conveyor 1, facing the insertion head 6.
is provided.

Two guide bars 85A, 85 are provided on the top surface of the bed 84.
A guide head 86 is mounted on the guide bars 85A, 85B so as to be slidable in parallel to the central axis of the cylinder bore Sb. A cylinder 87 is attached to the left side of the bed 84, and the tip of its piston rod 87A is fixed to the guide head 86, and the operation of the cylinder 87 causes the guide head 86 to reciprocate. The thrust force of the cylinder 87 is set smaller than the sum of the thrust forces of the cylinders 62A to 62D for inserting the piston P described above. The guide head 86 has a cylinder bore Sb.
Four guide forks 88A to 88 at the same pitch interval as
D is attached.

As shown in FIGS. 7 and 10, the guide fork 88A
~88D has a bifurcated tip, enters the cylinder bore S5 across the crankshaft Cr, and comes into contact with the large end face of the connecting rod C at the forward end (right end) of the guide head 86. . As shown in FIGS. 7 and 9, the large end of the connecting rod C has a
Since the bolts 89A and 89B for tightening the connecting rod cap are inserted, the guide forks 88A to 88D avoid the bolts 89A and 89B and come into contact with the large end face of the connecting rod C. ,R
A shaped relief is formed. In order to insert the piston P, move the pistons 63A to 63D forward and press the push plates 68A to
As the 68D moves forward, the piston P moves into the cylinder bore S5.
When the guide forks 88A to 88D are pushed in, the tips of the guide forks 88A to 88D remain in contact with the large end of the connecting rod C, and the guide forks 88A to 88D move backward (move leftward) due to the difference in thrust between the cylinders.
and guide the large end of the connecting rod C to the crankshaft C.

Next, the piston assembling operation of the automatic piston assembling apparatus of the present invention will be explained.

After actuating the cylinder 7 to move the insertion head 6 backward to the rear end, actuate the cylinder 10 to move the swivel head 4
Rotate 90 degrees counterclockwise from the state shown in Figure 1.

When the turning operation is completed, the cylinder 7 is operated again to advance (lower) the insertion head 6 until the abutting plate 14 hits the stopper 15. Next, the pallet P carried directly under the insertion head 6 and the piston P thereon are sandwiched by operating the piston ring compression device 35 to compress the piston ring Pr, and then the cylinders 32A to 32D for pushing up are operated. Then, the four pistons P are simultaneously pushed up and pushed into the piston holding cylinders 49A to 49D of the insertion head 6. As described above, the piston holding cylinders 49A to 49D are supported by the insertion head 6 in a floating manner, so even if there is a slight deviation in the center position between the piston P and the piston holding cylinders 49A to 49D, the piston P will not move. Then piston holding cylinder 49A
~49D moves to smoothly insert the piston P. Operate the cylinder 7 to move the insertion head 6 back (raise)
After that, the cylinder 10 is operated to rotate the swivel head 4 90 degrees clockwise. Connecting rod C
There is only a slight gap between the large end of the piston and the inner peripheral surface of the piston holding cylinders 49A to 49D, and the connecting rod C is perpendicular to the direction of pivoting of the connecting rod C with respect to the piston P. Since the swivel head 4 is rotated within a plane, the piston holding cylinder 49 is
Since the position of the connecting rod C hardly shifts within A to 49D, there is no problem in the assembly operation. Next, the cylinder 7 is actuated again to advance the insertion head 6,
When the abutment plate 14 comes into contact with the stopper 15, the front end of the insertion head 6 stops at a position slightly before hitting the cylinder head mounting surface Sh, as shown in FIGS. 7 and 10. Next, the cylinder 87 is actuated to move the guide head 86 forward (move to the right), and the guide forks 88A to 88D are inserted into the cylinder bore Sb. Subsequently, the cylinders 62A to 62D are operated simultaneously, and the piston P is pushed by the push plates 68A to 68D.
into the cylinder bore Sb. As described above, the push plates 68A to 68. D and piston holding cylinders 49A to 49
Since D is supported so that it can float, even if there is a slight misalignment between the piston P and the cylinder bore S, the cylinder bore S
, the piston holding cylinders 49A to 49D and the push plates 68A to 68D move to smoothly insert the piston P. In addition, since the piston P and the connecting rod C are inserted while being sandwiched between the guide forks 88A to 88D and the push plates 68A to 68D, the connecting rod C does not wobble during the insertion operation, and the crankshaft Cr
The large end of the connecting rod C can be smoothly guided. When the insertion operation is completed, the cylinders 62A-6
2D to move the push plates 68A to 68D backward, and at the same time actuate the cylinder 87 to move the guide head 86 backward (
After moving to the left), the Ripter 82 is lowered, the cylinder conveyor 1 is operated to send the cylinder block S that has been assembled to the next station, and a new cylinder block S is carried in, and the Ripter 82 is raised. Mounting tool 83
, and perform the piston assembly operation described above again.

According to the present invention, the piston and the connecting rod assembled thereto can be transported in a vertical state, and the cylinder block to be assembled with the piston can be transported with the central axis of the cylinder bore in a horizontal state. Done,
Furthermore, it is possible to automatically assemble pistons and cylinder bores that are oriented at 90 degrees. As detailed above, the present invention is not limited to the configurations shown in the examples, and modifications are expected without departing from the technical idea of the present invention as described in the claims. By the way.

[Brief explanation of the drawing]

Fig. 1 is an overall front view of the automatic piston assembly device of the present invention, Fig. 2 is a plan view thereof, Fig. 3 is a right side view, Fig. 4 is a longitudinal sectional view of the piston ring compression device, and Fig. 5 is a plan view including a cross section of the same part, and FIG. 6 is a pallet Pb for loading and unloading pistons.
7 is a cross-sectional view of the insertion head 6, FIG. 8 is a partially sectional left side view of the insertion head 6, and FIG. 9 is a view taken from A--A in FIG. 7. A cross-sectional view and FIG. 10 are vertical cross-sectional front views of the insertion head 6.

Claims (1)

[Claims] 1. With the top side up and the connecting rod assembled with the piston suspended, the piston transport conveyor that transports the pallet on which the piston is placed to and from the piston assembly position and the oil pan mounting surface are perpendicular to each other. a cylinder block transport conveyor for transporting cylinder blocks into and out of a piston assembly position; a column provided upright on the piston assembly device; and a swivel head supported on the column so as to be rotatable and indexable in a vertical plane; an indexing drive source provided on the column for rotating and indexing the swivel head;
an insertion head provided on the swivel head so as to be able to reciprocate and slide parallel to the rotation plane of the swivel head; a reciprocating drive source provided on the swivel head for reciprocating the insertion head; and the insertion head. a piston holding tube into which pistons can be inserted, which are provided at the same pitch intervals as the cylinder bores and in the same number as the cylinder bores; An automatic piston assembly device comprising a piston push rod and a piston push rod.