The present invention relates to a high speed plating apparatus and, more particularly, to an apparatus for consecutively plating a number of works at a high speed. An object of the present invention is to automatically and efficiently effect the plating treatment and to reduce the size of the high speed plating apparatus in order to reduce the area occupied thereby.
The present invention will now be described in connection with one embodiment thereof with reference to the accompanying drawings,
- Fig. 1 is a top plan view showing an apparatus according to the present invention; Fig. 2 is an enlarged section taken along line II - II of Fig. 1; and Fig. 3 is a sectional view- showing the transferred state of the connecting rod used as a work to be plated.
A connecting rod 1 to be used in an internal combustion engine is shown as an example of a work to be plated in the accompanying drawings.
The connecting rod 1 is formed with a larger end portion la, a smaller end portion lb and holes, and the smaller end portion lb has its inner circumference plated with copper in the present embodiment.
Reference letter A appearing in the drawings indicates a treating bath for effecting a plating treatment, and treatments before and after the plating treatment.
That treating bath is formed to have a round shape in a top plan view and to have its portion recessed in a sector shape thereby to from a notched portion 2 and its other portion radially divided into seven bathes a1, a2, a3, a4, a5, a6 and a7.
The aforementioned notched portion 2 is a place in which the connecting rod 1 is attached to or detached from a later-described transfer machine B. The connecting rod I is clockwise transferred from the stating point of the notched portion 2 by the action the transfer machine B until it is again returned to that starting point.
Of the seven bathes a1 to a7 formed in the treating bath A, on the other hand, the first bath a1, as viewed from the notched portion 2 in the transferred direction of the connecting rod 1, is stored with a deoiling liquid, which is composed mainly of sodium hydroxide, thereby to effect the deoiling treatment of the smaller end portion lb of the connecting rod 1.
Next, the second bath a2 is stored with water thereby to rinse away the deoiling liquid which has wetted the smaller end portion lb of the connecting rod 1 in the aforementioned first bath ale
The rinsing operation in the second bath a2 is called the "recovery rinsing operation" because the deoiling liquid is recovered into the first bath a1.
Next, the third bath a3 is stored with pure water and has this pure water circulated a cleaner (although not shown) thereby to effect the final rinsing operation of the smaller end portion lb of the connecting rod 1 as the treatment prior to the plating operation.
The fourth bath a4 is a bath for effecting the plating operation, in which the plating liquid is not reserved but a later-described plating apparatus C is accommodated.
The fifth bath a is stored with water thereby to rinse the smaller end portion lb of the connecting rod 1, which has been plated in the aforementioned fourth bath a4.
The sixth bath a6 is stored with pure water thereby to rinse away the plating liquid which is left unremoved by the rinsing operation in the aforementioned fifth bath a5. The plating liquid thus rinsed away is allowed to overflow until it is returned to the fifth bath a5.
Thus, the rinsing operations in the aforementioned fifth and sixth bathes as and a6 are called the"first and second rinsing operations", respectively, because the plating liquid is recovered.
Next, the seventh bath a7 is stored with pure water and has this pure water circulated through a cleaner (although not shown) thereby to effect the final rinsing operation of the smaller end portion lb of the connecting rod 1 as the treatment after the plating operation.
On the other hand, the aforementioned transfer machine B is concentrically disposed above the center of the aforementioned treating bath A and is constructed of a disc-shaped turntable bl and a clamping mechanism b2 which is disposed at the outer circumferential portion of the lower side of the turntable bl.
The motor 3 is made operative to intermittently feed the turntable b1 clockwise a predetermined angle and is placed on a platform 6. This platform 6 is so constructed that it slides up and down above a frame 5 through guide rods 8 and is connected through a rod 7 to a hydraulic or pneumatic cylinder 4 which is connected to the lower side of the frame 5.
Reference numeral 10 indicates a hydraulic or pneumatic cylinder which is connected to the side of the frame 5 and which has its rod 10a connected to a locate pin 11. This locate pin 11 is fitted, when in its protruding position, in the smaller end hole of the connecting rod 1 thereby to position the connecting rod 1 such that the latter vertically depends.
On the other hand, the aforementioned clamping mechanism b2 is composed of eight sub-mechanisms which are equidistantly arranged to correspond.to the notched portion 2 and the respective bathes a -to a7 of the treating bath A thereby to retain and clamp the connecting rod 1 at its larger end portion la.
Numeral 13 indicates a chuck, e.g., a collet chuck of the known type, which has its leading end portion divided in an opeable manner through a slit 14 and its base portion screwed on a supporting member 15.
This supporting member 15 can be supported through two guide rods 17 in a manner to move back and form radially of the turntable b1 upon a support 16, which is fixed to the lower side of the turntable b , so that the leading end portion of a control rod 18 is urged by the action of a spring 20 to push the leading end portion of the chuck 13, whereby it opens outward the chuck 13 thereby to hold the larger end portion la of the connecting rod 1.
On the other hand, the release of the support by the chuck can be effected -by pushing the aforementioned control rod 18 outward, i.e., in the direction to protrude from the chuck 13 by the action of the hydraulic or pneumatic cylinder which is mounted on the platform 6 of the aforementioned motor 3.
Numeral 21 indicates a spring which is made operative to bias the aforementioned supporting member 15 in a direction apart from the support 16.
On the other hand, the plating apparatus C, which is mounted in the fourth bath a4 of the aforementioned treating bath A, is constructed of a pair of wall members c1 and c2 which are so arranged to face each other that they can move t.oward and apart from each other.
Those wall members c1 and c2 are disposed in the bath a4 thereby to clamp the smaller end portion lb of the connecting rod 1 inbetween from both its sides. One wall member c has its wall surface opened to form a plating liquid supply passage 22b, whereas the other wall member c2 has its wall surface opened to form a recovery passage 28a so that the plating chamber including the inner surface of the smaller end portion of the connecting rod 1 therein is provided when the two wall members c1 and c2 are closed. Numerals 23 and 30 indicate seal members which are disposed on the abutting portions against the smaller end portion lb of the connecting rod 1. Those seal members 23 and 30 are made of rubber or a soft synthetic resin thereby to hold the liquid-tightness between an opening 22a and the smaller end portion lb.
On the other hand, the other wall member c2 is made of a material having an insulating property such as a synthetic resin.
Numeral 24 indicates a hydraulic or pneumatic cylinder which is fixedly attached to the outer surface of the outer wall of the bath a4 and which has its rod 24a extending through the outer side wall of the bath a4 until it is connected to the wall member c2 through a conducting member such as a mounting plate 25 and a connecting shaft 26, which are made of aluminum.
As a result, the wall member c2 is displaced in accordance with the operation of.the aforementioned cylinder 24 so that it can move toward and away from the facing wall member cl.
Numeral 27 indicates guide rods which are made operative to guide the operation of the aforementioned wall member c2.
As a result, the aforementioend supply passage 22b and recovery passage 28b are connected at a state, in which the wall members cl and c2 clamp the smaller end portion lb of the connecting rod 1, through said smaller end portion lb and through the openings 22a and 28a opened toward both the ends of the former.
Numeral 29 indicates a communication passage which is opened in the bottom of the bath a4 and connected with the aforementioned plating tank thereby to recover the plating liquid from the recovery passage 28 into the plating liquid tank.
Numeral 31 indicates an electrode which is so disposed in the aforementioned opening 28a as to protrude from the inner side of the wall member c2. That electrode 31 is inserted into said smaller end portion lb, at the state in which both the wall members c1 and c2 clamp the smaller end portion lb of the connecting rod 1, and is usually connected with the plus terminal of a power source.
Numeral 33 indicates an electrode member which is buried in the upper portion of the wall member c2 thereby to connect the connecting rod 1 with.the minus terminal of the power source.
As a result, the connecting rod 1 to be plated acts as the minus electrode, whereas the electrode 31 into which the smaller end portion lb of the connecting rod 1 is inserted, acts as the plus electrode so that the smaller end portion lb of the connecting rod 1 has its inner circumference electrolytically plated.
In the first bath a1 of the aforementioned treating bath A, incidentally, there is disposed a deoiling bath D which has a construction substantially similar to that of the aforementioned plating apparatus C so that the deoiling treatment becomes the so-called "electrolytically deoiling treatment".
More specifically, the smaller end portion Ib of the connecting rod 1 is wholly deoiled by being dipped in the deoiling liquid of the bath a1 and then has its inner circumference electrolytically deoiled.
In the deoiling apparatus D thus far described, the deoiling liquid is supplied to the smaller end portion lb of the connecting rod 1 by way of the openings 22a and 28a of the wall members d1 and d2 of that apparatus D and by way of the supply and recovery passages 22b and 28b communicating with those openings 22a and 28a, and the connecting rod 1 acts as the plus electrode whereas the electrode 31 acts as the minus electrode so that the electric current flows in the direction opposite to that of the plating treatment.
Thus, the inner circumference of the smaller end portion lb of the connecting rod 1 is electrolytically deoiled, as has been described hereinbefore, so that its deoiling treatment can be effected within a short time period and without fail.
In the plating apparatus thus constructed, the connectinc rod 1 is attached to and held on the clamping mechanism b2 in the notched portion of the treating bath A.
More specifically, the the connecting rod 1 has its larger end portion la fitted and held in the chuck 13 of the clamping mechanism b2 and its smaller end portion lb fitted in the locate pin 11 so that it is held in position in the transfer machine B.
Moreover, the turntable b1 is lifted by the cylinder 4 and is then turned by the motor 3 thereby to transfer the connecting rod 1 from the notched portion 2 to the first bath ale
When the connecting rod 1 is brought to a position above the first bath a1, the turntable b1 is again moved down by the cylinder 4 so that the smaller end portion lb of the connecting rod 1 is deoiled in that bath a1.
When in the aforementioned deoiling treatment, on the other hand, a new connecting rod 1 is attached to and held in the clamping mechanism b2 corresponding to the notched portion 2.
This attachment of the new connecting rod 1 is similarly performed during each of the later-described respective treatments so that the plating treatment, the pretreament and the posttreatment of the connecting rod 1 are simultaneously effected in the respective bathes a1 to a7.
After the deoiling treatment, moreover, the turntable b1 is again lifted and turned to transfer the connecting rod 1 to the second bath a2.
Next, the turntable b1 is moved down so that the smaller end portion lb of hte connecting rod 1 is rinsed. After this rinsing operation, the turntable b1 is again lifted and turned to transfer the connecting rod 1 to the third bath a3' in which the connecting rod 1 is rinsed.
After the three pretreatments thus far described, the connecting rod 1 is plated in the fourth bath a4.
At a state in which the smaller end portion lb of the connecting rod 1 is accommodated in the bath a4, more specifically, the wall member c2 at the movable side is pushed by the cylinder 24 toward the wall member c1 at the stationary side so that the smaller end portion lb of the connecting rod 1 is clamped between the two wall members c1 and c2.
In accordance with the operation of the aforementioned wall member c2' on the other hand, the abutment member 33 carried on the wall member c2 abuts atainst the larger end portion la of the connecting rod 1 thereby to displace the supporting member 15 toward the support 16 through said larger end portion la against the action of the spring 21.
At a state in which the smaller end portion lb of the connecting rod 1 is clamped between the wall members c1 and c2, the plating liquid flows from the supply passage 22b and the opening 22a through the smaller end portion Ib into the opening 28a and the recovery passage 28 thereby to plate the inner circumference of said smaller end portion lb.
During the aforementioned plating treatment, incidentally, even if the plating liquid should leak out of the openings 22a and 28a and the respective passages 22 adn 28 of the wall members c1 and c2 or out of the smaller end portion lb, it is reserved in the bath a4 and prevented from being splashed to the outside.
Thus, if the plating treatment is finished, the supply of the plating liquid is stopped, and the wall member c2 at the movable side leaves the wall member c1 at the stationary side. Accordingly, the supporting member 15 is urged to leave the support 16 by the action of the spring 12 so that the smaller end portion lb of the connecting rod 1 leaves the wall member cl at the stationary side.
Moreover, the turntable bl is lifted so that the connecting rod 1 escapes from the bath a4 until it is transferred to the next fifth bath a5, in which it is rinsed.
Likewise, the connecting rod 1 is consecutively transferred to the sixth and seventh bathes a6 and a7, in which it is rinsed to finish the posttreatment.
Thus, after all the treatments have been finished, the connecting rod 1 is again returned to the notched portion 2 of the treating bath A, in which it is removed at the same state from the clamping mechanism b2 and is replated by a new connecting rod 1.
All the treating operations other than the attachment and detachment of the connecting rod 1 to and from the transfer machine B are automatically accomplished in the aforementioned manners, and the plural, i.e., seven connecting rods 1 can be treated, pretreated and posttreated simultaneously and continuously:
Since the present invention has the construction thus far described, the holes of the work and the openings formed in the respective clamping members are made to communicate by clamping the work from both the sides of the holes thereof by means of the paired clamping members so that the plating liquid supply and recovery passages leading to those openings are made to communicate through those holes. Since the electrodes are simultaneously inserted into the holes, moreover, the inner circumferences of the holes formed midway are electrolytically plated by supplying the plating liquid from the supply passage to the recovery passage so that the plating treatment of the inner circumferences of said holes can be effected automatically and efficiently.