GB1561255A - Surfacing of valves for internal combustion engines - Google Patents

Description

(54) IMPROVEMENTS IN OR RELATING TO THE SURFACING OF VALVES FOR INTERNAL COMBUSTION ENGINES (71) We, INSTITUT ELECTROSVAR KI IMENI E.O. PATONA AKADEMII NAUKUKRAINSKOISSR, a Corporation organised and existing under the laws of the Union of Soviet Socialist Republics, of ulitsa Gorkogo, 69, Kiev, U.S.S.R., do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: The present invention relates to apparatus for surfacing the seating surfaces of valves for internal combustion engines.

According to the present invention, there is provided apparatus for surfacing valves for internal combustion engines by fusing heat resistant hard alloy rings on the seating surfaces of the valves, said apparatus comprising a manipulator movable about a substantially vertical axis between a receiving zone at which the manipulator receives the valve and the ring to be fused thereon, and a fusion zone at which the manipulator presents the valve with its head downwards and with the ring assembled on the valve, a heater at a fusion zone for fusing the ring to the valve head, a feed mechanism arranged to feed the valve from the manipulator to the heater, a clamping device arranged to hold the valve in a position for fusion of the ring by the heater, cooling means for directing coolant onto the valve held by the clamping device, a discharge chute for discharging the surfaced valve after release from the clamping device, pivotal support means carrying the feed mechanism, the cooling means, and the discharge chute, and drive transmitting means connecting the pivotal support means for movement with the manipulator such that when the manipulator is positioned in the receiving zone the pivotal support means is positioned to locate the cooling means and the discharge chute beneath the heater, and when the manipulator is positioned in the fusion zone, the pivotal support means is positioned to locate the feed mechanism beneath the heater.

An embodiment of the invention will now be described, by way of example only, with reference to the accompanying diagrammatic drawings, in which: Figure 1 is a schematic front elevation of apparatus for surfacing the seating surfaces of internal combustion engine valves; Figure 2 is a section, to an enlarged scale, and partly cut-away on line II-II in Figure 1; Figure 3 is a fragmentary side elevation, partly in section, to an enlarged scale and in the direction of arrow A in Figure 1; Figure 4 is a section to a further enlarged scale on line IV-IV of Figure 2; Figure 5 is a perspective view, to an enlarged scale of a clamp operating mechanism; Figure 6 is a section on line VI-VI in Figure 4 and showing the position of clamps in a valve-receiving zone and in a valve surfacing zone; Figure 7 is a section, to a further enlarged scale, on line VII-VII in Figure 2 and showing a discharge chute; and Figure 8 is a section on line VIII-VIII in Figure 7.

As shown in Figure 1 the apparatus for surfacing the seating surfaces of valves for internal combustion engines, comprises a frame consisting of a unit 1 and a unit 2.

The unit 1 comprises a feed mechanism 3 for feeding valves 4, a feed mechanism 5 for feeding rings 6 of a heat resistant hard alloy to be fused onto the seating surfaces of the valves, and a manipulator 7 (Figures 1 and 2) for receiving the valves 4 and the rings 6 at a receiving zone, assembling them and conveying them to a fusion zone. A pivotal support in the form of a platform 8 (Figures 2 and 3) is mounted inside the unit 1 and carries a feed mechanism 9 for feeding the valve/ring assembly at the fusion zone, a coolant sprayer 10, and a discharge chute 11.

At the fusion zone, a heater is mounted in the unit 2 (see Figure 3), the heater being a high frequency inductor 12 the operating frequency of which depends on the size of valves, and is for example within the range of 2400-8000 cycles per second. In the same unit a clamping device is mounted comprising drives (not shown) for clamping and rotating the valve 4, the clamping device being in the form of a chuck 13 arranged to grip the valve 4 at the end of its stem and to rotate the valve about its axis.

The feed mechanism 5 for feeding the rings 6 (Figures 1 and 2) to be fused on the valves 4 is mounted on a bracket 14 (Figure 1) and comprises a sloping conveyor chute 15 which is rectangular in cross-section in order to provide rolling motion of the rings 6 in an upright position. A sloping trough 16 (Figure 2) extends transversely of the chute 15 and provides for sliding motion of the ring 6 on a lateral surface thereof, substantially in a horizontal position.

On the conveyor chute 15 there is mounted a device 17 (Figures 1 and 2) for delivering the rings 6 to the trough 16 singly from the chute 15. The device 17 comprises a pivoted rocker arm 18 operative to release individual rings. The detailed construction and operation of such a device will be readily apparent to those skilled in the art and will not be described herein.

The valve feed mechanism 3 is mounted on a bracket and comprises guides formed by two parallel bars or plates 19 and 20 (Figures 1 and 2) on which the head of the valve 4 rests when the valve is conveyed with its stem downwards. A device 22 for delivering the valves one at a time is mounted on a bracket 21 (Figure 2); the construction of this latter device will also be readily apparent to those skilled in the art.

The manipulator 7, as shown in Figure 4, comprises a cylindrical housing 23 built into the unit 1 and mounting via bearings 24, a vertical drive shaft 25. A bushing 27 is fixed onto the shaft 25 by a key 26, a lug 28 being rigidly mounted on the bushing 27. The lug 28 is linked to a rod of an air cylinder 29 which is actuable to rotate the shaft 25 through 90 .

The shaft 25 carries at its upper end a bearing assembly 30, and at its lower end a toothed sector 31 (Figures 3 and 4). The bearing assembly 30 mounts a horizontal shaft 32 (Figure 4). A bevel pinion 33 is fixed at one end of the horizontal shaft 32 and meshes with a stationary bevel toothed sector 34. At the other end of the horizontal shaft 32 an actuator 35 is mounted; pivoted on a housing 36 of this actuator are clamping jaws 37 and 38 (Figures 4 and 5) for clamping the valve 4, and a support 39 rotatable in the vertical plane and adapted to receive the ring 6 and to move the ring onto the stem of the valve 4. As shown in Figures 5 and 6, on the internal surface of each clamping jaw 37 and 38 there are grooves 41 and 42, respectively. The grooves are disposed opposite each other, and on closing the jaws 37 and 38 they define a space for the stem of the valve 4 which is positioned and clamped therein.

In the housing 36 of the actuator 35 there is mounted a mechanism 43 (Figure 4) for opening and closing the clamping jaws 37 and 38. This mechanism comprises a rod 44 mounted in guiding apertures of the housing 36 so that one end thereof extends beyond the housing. A shoe 45 is rigidly secured to the rod 44. A semi-cylindrical casing 46 (Figures 4 and 5) is fixed to the shoe 45, and has helical grooves 47 and 48 (Figure 5) extending in opposite directions and accommodating rollers 49 and 50 which are carried by arms 51 and 52, respectively, of the clamping jaws 37 and 38. The rod 44 is biased axially by a spring 53, one end of said spring engaging the shoe 45 and the other end engaging the housing 36.

The support 39 is operatively connected to the mechanism 43 for opening and closing the clamping jaws 37 and 38. This operative connection is formed by a toothed rack 54 secured to the shoe 45, a toothed sector 55 fixed on the support 39, and m idle pinion 56 which is in meshing engagcment with the toothed rack 54 and the toothed sector 55.

A stationary stop 58 is carried on an arm mounted on a cover 57 of the housing 23 of the manipulator 7, and a movable stop 59 is mounted on the unit 2.

The movable stop 59 comprises a roller 60 mounted on a piston rod 61 of a fluidactuated cylinder 62.

A vertical shaft 63, journalled at 64 and 65, carries the platform 8 (Figures 2, 3) which is rotatable in a horizontal plane.

Mounted on the platform 8 is the valve feed mechanism 9 for feeding the valves to the inductor 12 and to the chuck 13. This mechanism comprises a fluid-actuated cylinder 66 having a tapered cup 67 mounted on the body of the cylinder 66 and a pad 69 mounted on a piston rod 68 of the cylinder 66.

As was mentioned earlier, the discharge chute 11 is also mounted on the pivotal platform 8, this chute being in the form of a bent tube 70 (Figure 7) having a vertical and an inclined portion. The coolant sprayer 10 is mounted at the inlet end of the discharge chute 11, that is at the top of the vertical portion thereof, and comprises a hollow annulus 71 having a plurality of ports or tubes 72 on the upper side thereof. This arrangement prevents the sprayer from being blocked by molten metal from the ring. The cavity of the annulus 71 communicates with a coolant source 73.

A tube 74 is attached to the wall of the unit 2 of the frame, this tube forming an extension of the discharge chute 11, when the chute 11 and the coolant sprayer 10 are positioned under the inductor 12, as shown in Figure 7.

The bottom side of the tube 70 is perforated to permit the discharge of coolant therethrough. A pocket with a discharge tube 75 is attached to the external surface of the tube 70 in the area of the perforations to collect the coolant and to direct same into a discharge tank 76.

To ensure the correct vertical positioning of the valve 4 in the tube 74, a stop such as a screw 77 is mounted in the unit 2 to serve as an abutment for the valve head, and the bottom side of the tube is provided with a slot 78 through which the valve stem can project downwardly (see Figure 8).

The platform 8 is operatively connected to the manipulator 7 through a transfer gear 80 (Figure 3) so that the platform pivots when the manipulator is moved between the receiving and fusion zones. This transfer gear 80 is formed by a toothed section 81 (Figure 4) which is attached to, or formed on the periphery of, the platform 8, and which meshes with the toothed sector -31 rigidly mounted on the vertical shaft 25 of the manipulator 7.

In order to afford a clearer understanding of the apparatus an automatic mode of operation thereof will now be described. A control system for providing this automatic mode of operation will be apparent to those skilled in the art and will not be described herein.

In the initial position, as shown in Figures 1, 2 and 7 the actuator 35 is in the receiving zone of the valve 4 and of the ring 6 to be fused on the valve, while the platform 8 is positioned in such a manner that the discharge chute 11 and the sprayer 10 mounted thereon are under the inductor 12. At the same time the rod 44, as a result of interaction with the stationary stop 58 (Figures 1 and 4), is in a position wherein the clamping jaws 37 and 38 are open at an angle cpl (Figure 6) which is sufficient for the stem of the valve 4 to pass therebetween and the support 39 in a substantially horizontal position.

One valve 4 and one ring 6 are separated from a file of valves and rings moving along the guides 19 and 20 and the conveyor chute 15 by the devices 22 and 17 and are advanced towards the actuator 35. The valve 4, positioned stem downwards, is introduced into the space between the clamping jaws 37 and 38, while the ring 6, sliding on its lateral surface along the sloping chute 16 is fed to the support 39.

Then the air cylinder 29 is actuated the rod of which, moving the carrier 28, rotates the vertical shaft 25 (Figure 4).

The actuator 35 mounted on the horizon tal shaft 32 is rotated by the vertical shaft 25 in the horizontal plane in the direction of the inductor 12. The vertical shaft 25, through the transfer gear 80 also pivots the platform 8 to position the feed mechanism 9 under the inductor 12, this latter feed mechanism serving to feed the valve to the chuck 13. The horizontal shaft 32, rotating about the vertical axis, also rotates about its own axis due to rolling of its bevel pinion 33 along the stationary toothed sector 34.

Thus, the actuator 35 performs rotary motion both about a horizontal and a vertical axis.

At the start of the movement of the actuator 35, the rod 44 disengages from the stationary stop 58 and rises under the action of the spring 53. This movement effects, via the shoe 45, upwards movement of the toothed rack 54 which, through the idle pinion 56, rotates the toothed sector 55 of the support 39. As a result the support 39 rotates in the vertical plane and positions the ring 6 on the stem of the valve 4.

Simultaneously with the above, the casing 46, connected to the shoe 45, moves upwards and the lower surfaces of the helical grooves 47 and 48 act on the rollers 49 and 50 (Figures 4 and 5) to move together the arms 51 and 52, which, in turn, causes the clamping jaws 37 and 38 to close and to clamp the stem of the valve 4 accommodated in the space formed by the grooves 41 and 42.

Thus, at the start of the motion of the actuator 35, at the moment when the support 39 positions the ring 6 on the stem of the valve 4, the stem is clamped by the jaws 37 and 38.

Moving from the initial position, that is from the receiving zone of the valve 4 and the ring 6, to the fusion zone, that is to the zone at which the heater (inductor 12) and associated components are located, the actuator 35 rotates through 1800 in a vertical plane through 90" in a horizontal plane.

The rotation of the actuator 35 in a horizontal plane is accompanied by pivotal movement of the platform 8. When the platform 8 reaches its end position, the feed mechanism 9 serving to feed the valve and ring to the inductor 12 is located beneath the inductor and also beneath the chuck 13.

On reaching the fusion zone, the actuator 35 having been rotated through 1800 in a vertical plane is orientated as indicated schematically at the right-hand side of Figure 4, that is with the free end of rod 44 projecting downwardly, and with the support 39 located above the clamping jaws 37 and 38, the valve carried by these jaws now being orientated so that its stem is upwardly directed.

When in the fusion zone the lower end of the rod 44 engages the roller 60 of the movable stop 59. Interacting with the roller 60, the rod 44 is slightly retracted into the housing 36 of the actuator 35 against the bias of the spring 53. Simultaneously with this movement of the rod 44 and of the casing 46 connected to the former through the shoe 45, the surfaces of the helical grooves 47 and 48, acting on the rollers 49 and 50 of the arms 51 and 52, move apart the clamping jaws 37 and 38 to an angle (P2 (Figure 6) which is sufficient to release the stem of the valve 4 but insufficient to allow the ring 6 which rests on the jaws 37 and 38, to fall through the jaws.

Upon release from the clamping jaws 37 and 38, the valve 4, with the stem thereof still within the space formed by the grooves 41 and 42, moves freely down and rests with the surface of its head on the pad 69 of the feed mechanism 9.

At a command of the control system the cylinder 62 of the movable stop 59 is actuated to move, via the rod 61 and the roller 60, the rod 44 upwards to its maximum stroke and to move apart the jaws 37 and 38 at an angle 3 (Figure 6) sufficient for the ring 6 to fall therethrough. This movement of the rod 44 also causes, via the shoe 45, the toothed rack 54 and the idle pinion 56, the support 39 to pivot upwards thus vacating the space under the inductor 12 (Figure 4).

Guided by the internal tapered surface of the cup 67, the ring 6 is dropped on the head of the valve 4. The assembled valve, i.e. the valve 4 with the ring 6 resting on the head thereon, is then ready to be fused.

At a command of the control system the cylinder 66 (Figure 3) is actuated to raise the valve; when the end of the stem of the valve 4 reaches the opening of the chuck 13, the head of the valve 4 reaches the collar of the high frequency inductor 12, and the end of the stem presses a limit switch (not shown) mounted in the opening of the chuck 13.

The following commands are then given by the control system to close and rotate the chuck 13; to energize the high frequency inductor 12 and to move downwards the rod 68 with the pad 69 and thereafter to actuate the fluid cylinders 62 and 29 to withdraw the actuator 35 from the fusion zone.

The refractory alloy ring 6 melted in the high frequency current field is fused on the head of the valve 4 to which rotary motion is imparted in order to provide uniform distribution of the molten metal on its seating surface.

As indicated above, at a command of the control system the air cylinder 29 is actuated to return its piston rod into the initial position. In so doing, the rod moves in the same direction, the lug 28 thereby causing rotation of the vertical drive shaft 25 of the manipulator 7 (Figure 4). As a result the vertical drive shaft 25 rotates, in a horizontal plane, the actuator 35 mounted on the horizontal shaft 32 and returns the actuator into its initial position, that is into the receiving zone to receive the next valve and the ring to be fused thereon; in addition the shaft 25 moves through the transfer gear 80 the pivotal platform 8.

At the beginning of the return movement of the actuator 35, the rod 44 disengages from the roller 60 of the movable stop 59 and is moved by the bias of the spring 53, the shoe 45 moving with the rod 44. This movement of the shoe 45 effects via the toothed rack 54, the idle pinion 56, and the toothed sector 55, rotation of the support 39 into its initial position; also the casing 46, acting with the surfaces of the helical grooves 47 and 48 on the rollers 49 and 50 of the arms 51 and 52, brings these arms together thereby causing the clamping jaws 37 and 38 to close.

When the fluid cylinder 29 has functioned to return the actuator 35 into its initial position it has caused the platform 8 to pivot to a position at which the discharge chute 11 with the sprayer 10 mounted thereon are positioned under the inductor 12 (Figure 7).

At a command issued by the control system, coolant is supplied to the sprayer 10 to be directed through the tubes 72 onto the head of the valve 4 to ensure solidification of the deposited metal. The coolant runs off along the discharge tube 75 into the tank 76.

When the actuator 35 (Figures 3, 4) reaches its initial position, the end of its rod 44 engages the stationary stop 58 thereby causing the clamps 37 and 38 and the support 39 to return into the intial position.

The actuator 35 is then ready to receive the next valve and ring, these being fed after the surfacing process on the preceding valve has been completed.

At the completion of the surfacing operation of the preceding valve, commands are given to stop the supply of coolant and to open the chuck 13. When the chuck 13 is opened, the surfaced valve 4 falls through the opening of the sprayer 10 (Figure 7) into the discharge chute 11 and falls therefrom into the tube 74. At the outlet end of the tube 74 the head of the valve 4, hits the screw 77 and is turned stem downwards, the valve thereafter slides along guides 79 to be discharged from the apparatus (Figures 7 and 8).

The actuator 35 with the next valve and ring is then advanced towards the fusion zone and the foregoing cycle is repeated.

By mounting the coolant sprayer, the feed mechanism for feeding the valve and ring from the manipulator to the heater and discharge chute on a common platform which is operatively connected to the manipulator in the manner described, there is thus provided in a simple manner according to the movement of the manipulator, alternate positioning under the heater of the feed mechanism on the one hand, and the discharge chute and sprayer on the other hand.

This in turn makes it possible to carry out at one operating station surfacing and cooling, and auxiliary operations, such as, loading and removing the valve into, and from, the heater.

The apparatus described is relatively simple to control and to maintain, and is fail-safe in operation.

The manipulator described herein is also described and claimed in our co-pending application 17257/77. (Serial No. 1557912).

WHAT WE CLAIM IS: 1. Apparatus for surfacing valves for internal combustion engines by fusing heat resistant hard alloy rings on the seating surface of the valves, said apparatus comprising a manipulator movable about a substantially vertical axis between a receiving zone at which the manipulator receives the valve and the ring to be fused thereon, and a fusion zone at which the manipulator presents the valve with its head downwards and with the ring assembled on the valve, a heater at the fusion zone for fusing the ring to the valve head, a feed mechanism arranged to feed the valve from the manipulator to the heater, a clamping device arranged to hold the valve in a position for fusion of the ring by the heater, cooling means for directing coolant onto the valve held by the clamping device. a discharge chute for discharging the surfaced valve after release from the clamping device.

pivotal support means carrying the feed mechanism, the cooling means, and the discharge chute, and drive transmitting means connecting the pivotal support means for movement with the manipulator such that when the manipulator is positioned in the receiving zone the pivotal support means is positioned to locate the cooling means and the discharge chute beneath the heater. and when the manipulator is positioned in the fusion zone. the pivotal support means is positioned to locate the feed mechanism beneath the heater, 2. Apparatus according to claim 1.

wherein the drive transmitting means comprises a toothed sector rigid with a vertical drive shaft of the manipulator and a second toothed sector rigid with the pivotal support means.

3. Apparatus according to claim 1 or claim 2. wherein the cooling means comprises a coolant sprayer of annular form mounted at the inlet end of the discharge chute.

4. Apparatus for surfacing valves for internal combustion engines substantially as hereinbefore described with reference to the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (4)

**WARNING** start of CLMS field may overlap end of DESC **. from the manipulator to the heater and discharge chute on a common platform which is operatively connected to the manipulator in the manner described, there is thus provided in a simple manner according to the movement of the manipulator, alternate positioning under the heater of the feed mechanism on the one hand, and the discharge chute and sprayer on the other hand. This in turn makes it possible to carry out at one operating station surfacing and cooling, and auxiliary operations, such as, loading and removing the valve into, and from, the heater. The apparatus described is relatively simple to control and to maintain, and is fail-safe in operation. The manipulator described herein is also described and claimed in our co-pending application 17257/77. (Serial No. 1557912). WHAT WE CLAIM IS:

1. Apparatus for surfacing valves for internal combustion engines by fusing heat resistant hard alloy rings on the seating surface of the valves, said apparatus comprising a manipulator movable about a substantially vertical axis between a receiving zone at which the manipulator receives the valve and the ring to be fused thereon, and a fusion zone at which the manipulator presents the valve with its head downwards and with the ring assembled on the valve, a heater at the fusion zone for fusing the ring to the valve head, a feed mechanism arranged to feed the valve from the manipulator to the heater, a clamping device arranged to hold the valve in a position for fusion of the ring by the heater, cooling means for directing coolant onto the valve held by the clamping device. a discharge chute for discharging the surfaced valve after release from the clamping device.

pivotal support means carrying the feed mechanism, the cooling means, and the discharge chute, and drive transmitting means connecting the pivotal support means for movement with the manipulator such that when the manipulator is positioned in the receiving zone the pivotal support means is positioned to locate the cooling means and the discharge chute beneath the heater. and when the manipulator is positioned in the fusion zone. the pivotal support means is positioned to locate the feed mechanism beneath the heater,

2. Apparatus according to claim 1.

wherein the drive transmitting means comprises a toothed sector rigid with a vertical drive shaft of the manipulator and a second toothed sector rigid with the pivotal support means.

3. Apparatus according to claim 1 or claim 2. wherein the cooling means comprises a coolant sprayer of annular form mounted at the inlet end of the discharge chute.

4. Apparatus for surfacing valves for internal combustion engines substantially as hereinbefore described with reference to the accompanying drawings.