US2912826A

US2912826A - Valve for operating a pair of related devices

Info

Publication number: US2912826A
Application number: US667329A
Authority: US
Inventors: Kheng S Tan
Original assignee: International Harverster Corp
Current assignee: Navistar Inc
Priority date: 1957-06-24
Filing date: 1957-06-24
Publication date: 1959-11-17
Anticipated expiration: 1976-11-17

Description

Nov. 17, 1959 Filed June 24, 1957 K. S. TAN

VALVE FOR OPERATING A PAIR OF RELATED DEVICES 2 Sheets-Sheet l fzzdzz for F t 46 A .59, 4.9 mi

I 56 H. '1 l flgfzezqg Tan 7 Nov. 17, 1959 K. s. Tm 2,912,826

7 VALVE FOR OPERATING A PAIR OF RELATED DEVI CES Filed June 24. 1957 2 Sheets-Sheet 2 7?]? e229 Tan Mm W oQfiorz-zey United States Patent 6 VALVE FOR OPERATING A PAIR OF RELATED DEVICES Kheng S. Tan, Melrose Park, Ill., assignor to International Harvester Company, Chicago, 11]., a corporation of New Jersey Application June 24, 1957, Serial No. 667,329

4 Claims. (Cl. 60-97) apron and ejector of a scraper.

An object of the invention is to provide a valve that incorporates two valves into one.

Another object of the invention is to provide a valve that is compact and small and is inexpensive to make and whose parts can be replaced easily.

A further object of the invention is to provide a valve for a scraper that automatically times apron movement to ejector movement so that there is no requirement of judgment on the operators part.

The foregoing and other objects of the invention are attained by the construction and arrangement illustrated in the accompanying drawings wherein:

Figure 1 is a side elevational view of a two Wheel tractor and a two Wheel scraper hitched to the tractor;

Figure 2 is a schematic view of the apparatus of the present invention for operating the apron and ejector of the scraper;

Figure 3 is a partly side elevational and partly broken sectional view of the valve shown in Figure 2 with the valve being in one position;

Figure 4 is a view of the valve similar to the view of Figure 3 but with the parts thereof being in a different position;

Figure 5 is a view of the valve similar to the view of Figure 3 but with the parts thereof being in a third position, and

Figure 6 is a cross sectional view of the valve taken on the line 6-6 of Figure 3.

In the past it has been the practice to have one valve for directing fluid to the cylinder of the apron to raise the apron and a second valve for directing fluid to the cylinder of the ejector to move the ejector forward to dump the contents of the ejector and to retract the ejector and a third valve for directing fluid to the cylinder of the bowl to raise the bowl.

The invention proposes a valve for directing fluid to the cylinder of the apron of a scraper to raise the apron and for directing fluid to the ejector cylinder to move the ejector forward to dump the contents of the scraper and to retract the ejector. A control means is provided for directing fluid to the cylinder of the bowl to raise the bowl. This valve has the advantage of being compact and small and it incorporates two valves in one and is inexpensive to make and the parts of the valve can be replaced easily. With this valve the tractor operator has two levers for operating the scraper instead of three as used in the past thus making everything simpler to operate for the tractor driver. This valve automatically times apron movement to ejector movement so that there is no requirement of judgment on the tractor operators part.

In the drawings, 10 generally designates a two wheel tractor hitched to a two wheel scraper 11. The scraper 2 ice 11 is made up of a bowl 12, wheels 13, a gooseneck 14 pivoted to the bowl, an ejector 15 mounted on the bowl and an apron 16 pivoted on the bowl. The invention is concerned with a valve generally designated 17 mounted on the tractor for supplying fluid to the ejector 15 and the apron 16 for operating them. When it is desired to fill the scraper 11 with earth the bowl 12 is lowered and the apron 16 is raised to expose the opening 18 in the bowl with the ejector 15 being retracted. After the bowl 12 is filled with earth the bowl is raised up off the ground and the apron 16 is lowered to close the opening 18. The tractor 10 then pulls the scraper 11 to the place where it is desired to unload the earth and upon reaching this place the apron 16 is raised to expose the opening 18 and the ejector 15 is moved forward to push the earth out through the opening. Thus the apron 16 and the ejector 15 are a pair of related devices.

A pair of cylinders 19 are disposed at the sides of the apron 16 and each cylinder is pivoted to the bowl 12 and has a piston 20 and a piston rod 21 pivoted to the apron. A cylinder 22 is disposed centrally of the bowl 12 and is secured thereto and a piston 23 is disposed in the cylinder and a piston rod 24 is secured to the ejector 15. A cylinder 25 is pivoted to the bowl 12 and has a piston therein and a piston rod 26 p-rojectstherefrom and is pivoted to the gooseneck 14. A pump 27 is mounted on the engine of tractor 10 and is driven from the engine crankshaft and an oil reservoir 28 is formed in the hitch connecting the scraper to the tractor. A conduit 29 extends between the pump 27 and the reservoir 28. A control means 30 is mounted on the tractor and has levers 31 and 32 pivoted thereon. The control means 30 is a conventional selector valve. A conduit 33 extends between the pump 27 and the control means 30 and a conduit 34 extends between the reservoir 28 and the control means.

The valve 17 is comprised of a casing 35 having a chamber 36 circular in cross section and a chamber 37 circular in cross section separated from the chamber 36 by a partition 38. The chamber 36 has

circular grooves

39, 40 and 41 therein. The casing 35 is provided with

openings

42, 43 and 44 with the

openings

43 and 44 being in alignment and in communication with the chamber 36 through groove 39 and the opening 42 being at right angles to the

openings

43 and 44 and in communication with them. The casing 35 is also provided with an opening 45 in communication with chamber 36 through groove 40 and an opening 46 in communication with chamber 36 through groove 41. A passage 47 extends from openings 43 and 44- to the chamber 37. A plunger 48 is slidably disposed in the chamber 36 and has a circular head 49 of one diameter and a circular section 50 of a lesser diameter than the head and the portion of the section contiguous with the free end thereof is reduced in diameter to provide a shoulder 51. A recess 52 extends inwardly from one end of the plunger 48 and a recess 53 extends inwardly from the other end of the plunger and is of a smaller diameter than the recess 52 and merges with the recess 52 to form a shoulder 54 at the merger location. The partition 38 is provided with a circular aperture 55 and a piston 56 is slidably disposed in the aperture. The piston 56 is made up of two circular sections of different diameters so that a shoulder 57 is formed between the sections. The section of the piston 56 of larger diameter is formed with a groove and a collar 58 is disposed in the groove. The piston 56 is provided with a slot 59 intermediate its ends. A resilient means in the form of a coil spring 60 is disposed in the recess 52 of the plunger and bears against the shoulder 54 and the casing and urges the plunger toward the partition 38. A stop means in the form of a snap ring 61 is disposed in a circular groove in the section 50 adjacent the free end of the section of the plunger. A circular sleeve 62 is slidably mounted on the section 50 of the plunger and a resilient means in the form of a coil spring 63 is mounted on the section and bears against the head 49 and the sleeve and urges the sleeve toward the snap ring 61. A conduit 64 extends from the control means 30 to the opening 42 in the casing of the valve 17 and a conduit 55 extends from the opening 43 and in the casing of the valve and divides into branches 66 and 67 which lead to the head ends of the cylinders 19 for the apron 16. A conduit 68 extends from the opening 44 in the casing of valve 17 to the head end of the ejector cylinder 22 and a conduit 69 eX- tends from the rod end of the ejector cylinder to the opening 45 in the casing of the valve. A conduit 70 extends from the opening 46 in the casing of the valve to the control means 30. A conduit '71 extends from the control means 30 to the head end of the cylinder 25.

Assuming the bowl 12 is in raised position and the apron 16 is in lowered position covering the opening 18 of the bowl and that the ejector is retracted and it is desired to load the scraper. Referring to Figure 2 at lever 32 R means raise, 3" means hold and L means lower. The lever 32 is moved to L so that oil in the head end of cylinder drains out through conduit 71 into control means to conduit 34 into the reservoir 23. The oil is moved out of cylinder 25 by the weight of the bowl so that the bowl is in a lowered position with its cutting edge contacting the ground. The lever 32 is then moved to i so that oil flow into conduit 71 is closed oti by a closure in control means 39. Again referring to Figure 2 at lever 31 R means raise, H hold, L lower and F float. The lever 31 is moved to R. The pump 27 then moves oil through the control means 3%} through conduit 64 into opening 42 to fill groove 39, chamber 37 and passage 47 in valve 17 with oil. Under a predetermined pressure, say for example under 500 psi. pressure, pressure in chamber 37 cannot move piston 56 which is held back by the spring 60. Oil is then moved through opening 43 into conduit 65 and into conduits 66 and 67 to the head end of the apron cylinders 19 to raise the apron. Oil cannot fiow into the head end of the ejector cylinder 22 because oil is trapped in the rod end of the ejector cylinder by plunger 48 and sleeve 62. The lever 31 is now moved to H so that the apron 16 will be held in a raised position. In the H position a closure in the control means 30 shuts off flow to or from the conduit 64 and oil is pumped from pump 27 to conduit 33 through the control means into conduit 34 to reservoir 28 through conduit 29 baclt to the pump where this flow is repeated as long as the lever is held in the H position. The tractor It then pulls the scraper forward until the bowl 12 is filled with earth. The lever 31 is now moved to L so that the weight or" the apron 16 forces the oil out of the head ends of the apron cylinders 19 and the oil drains through conduit 65 through

openings

43 and 42 into conduit 64 through control means 3% into conduit 34 and into reservoir 28. The apron lld thus moves downwardly until it is in lowered position. The lever 32 is now moved to R so that oil from pump 27 moves through conduit 33 and control means 30 into conduit 71 to raise the bowl 12. The lever 32 is then moved to H position. The tractor in then pulls the scraper to the place where it is desired to deposit the earth in the scraper. The lever 31 is moved to R so that the apron 1a is raised to expose opening 18 in the bowl and upon the oil reaching the predetermined pressure oil behind the piston 56 and its collar 58 moves the piston to the right as shown in Figure 4 and the piston ofisets plunger 43 from its position against partition 38 allowing pressure from groove 39 work on the entire plunger area. The plunger 48 and the sleeve 62 move as a unit to the extreme right as shown in Figure 4 compressing spring 66 thereby connecting

openings

45 and 46. Oil in the rod end of the ejector cylinder 22 then flows through conduit 69 into opening 45' into groove 44 and around section 5i) of the plunger into groove 41 to opening 46 and then through conduit 70 through control means 30 to the reservoir 23. The pressure in the conduit 65 maintains the apron 16 in a raised position and oil under pressure flows through conduit 68 into the head end of the ejector cylinder 22 to move the ejector 15 forward to dump the earth in the bowl of the scraper. Oil in ti s,. e 72 of chamber 36 drains through a number of holes 73 in the casing 35 of the valve 17 and oil cannot flow through slot 5? into recess 52 of the plunger since the slot is closed oft" by the wall of the recess 53 of the plunger. By moving the lever 31 to L the control means 39 directs oil from the pump 27 into the opening 16 in the casing of valve 17. Since oil under pressure is directed into the opening 45 the force on the head of plunger is removed and spring 60 pushes the plunger back against the partition 33. As oil under pressure is delivered into opening 46 the sleeve 62 is pushed to the left as shown in Figure 5 causing the spring 63 to be compressed. Oil then passes through opening 46 into groove 41 around section 58 of the plunger into groove 3% through opening 45 into conduit 69 and then into the rod end of the ejector cylinder 22 causing the ejector 15 to retract. Oil from the head end of the ejector cylinder 2?. flows into conduit 63 through opening 44 into opening 42 into conduit 64 through control means 30 into conduit 34 to the reservoir 23. Oil from the apron cylinders 19 is moved through conduits 66 and 67 to conduit 65 into opening 43 through opening 42 into conduit 64 through the control means 35? to the conduit 34 into the reservoir 28. This flow from the apron cylinders 19 is caused by the weight of the apron 16 and the apron lowers itself as it moves the oil out of the head ends of the cylinders 19. The pressures in spaces 74 and 75 of chamber 36 are equal since there is communication between these spaces through slot 59 in the piston and the plunger 48 and sleeve 62 are in hydraulic balance. The spring 60 maintains the plunger 43 against the partition 38. The tractor it) then pulls the scraper to the place where it is desired to refill the scraper with earth and the operation is repeated.

What is claimed is:

1. Apparatus for providing fluid to actuate a first device and a second device related to the first device comprising a valve including a casing and a first opening in communication with the interior of the casing and a second opening in communication with the interior of the casing and a third opening in communication with the interior of the casing and a fourth opening in communication with the interior of the casing, fluid under a predetermined pressure flowing through the first opening and out the second opening to the first device to actuate the latter in one direction, a first means in the casing responsive to fluid pressure operative to cause communication between the third and fourth openings upon the fluid reaching the predetermined pressure so that fluid from the second device can drain through the third and fourth openings allowing fluid pressure from the second opening to actuate the second device in one direction, and a second means in the casing responsive to fluid pressure operative to cause communication between the third and fourth openings upon fluid under pressure being directed into the fourth opening so that fluid from the second device can drain through the first and second openings allowing fluid pressure from the fourth opening to actuate the second device in the opposite direction.

2. Apparatus for providing fluid to actuate a first device and a second device related to the first device comprising a valve including a casing provided with a first chamber therein and a second chamber separated from the first chamber by a partition provided with an aperture therein and a first opening in communication with the first chamber and a second opening in communication with the first chamber and a third opening in communication with the first chamber and a fourth opening in communication with the first chamber and a passage from the first opening to the second chamber, a plunger slidably positioned in the first chamber, a first resilient means bearing against the plunger and the casing and urging the plunger toward the partition, stop means on each end of the plunger, means slidably mounted on the plunger between the stop means, a second resilient means bearing against one of the stop means and the means slidably mounted on the plunger and urging the means toward the other stop means, and means slidably mounted in the aperture in the partition, fluid under a predetermined pressure flowing through the first opening and out of the second opening to actuate the first device and upon reaching the predetermined pressure fluid in the second chamber moving the means mounted in the partition toward the first chamber with the means moving the plunger against the pressure of the first resilient means allowing fluid from the second device to drain through the third and fourth openings and fluid flowing from the second opening to the second device to actuate the latter in one direction and upon fluid under pressure being directed into the fourth opening the first resilient means moving the plunger against the partition and the fluid moving the means slidably mounted on the plunger toward said one stop means against the pressure of the second resilient means and flowing to the second device to actuate the latter in the opposite direction and fluid from the second device flowing through the second and first openings to drain and fluid from the first device flowing through the second and first openings to drain allowing the first device to be moved in the opposite direction.

3. Apparatus for providing fluid to actuate a first device and a second device related to the first device comprising a valve including a casing provided with a first chember therein and a second chamber separated from the first chamber by a partition provided with an aperture therein and a first opening in communication with the first chamber and a second opening in communication with the first chamber and a third opening in communication with the first chamber and a fourth opening in communication with the first chamber and a passage from the first opening to the second chamber, a plunger including a head of one dimension and a section of a smaller dimension than the head positioned in the first chamber, a first resilient means bearing against the plunger and the casing and urging the plunger toward the partition, stop means on the free end of the section of the plunger, a sleeve slidably mounted on the section of the plunger, a second resilient means bearing against the head of the plunger and the sleeve and urging the sleeve toward the stop means, and a piston disposed in the aperture in the partition, fluid under a predetermined pressure flowing through the first opening and out the second opening to actuate the first device and upon reaching the predetermined pressure fluid in the second chamber moving the piston toward the first chamber with the piston moving the plunger against the pressure of the first resilient means to bring the third opening into com munication with the fourth opening allowing fluid to move from the second device through the third and fourth openings to drain and fluid flowing from the second opening to the second device to actuate the latter in one direction and upon fluid under pressure being directed into the fourth opening the first resilient means moving the plunger against the partition and the fluid moving the sleeve toward the head of the plunger against the pressure of the second resilient means and flowing to the second device to actuate the latter in the opposite direction and fluid from the second device flowing into the second opening through the first opening to drain and fluid from the first device flowing through the second opening and the first opening to drain allowing the first device to be moved in the opposite direction.

4. Apparatus for providing fluid to actuate a first device through .a first cylinder and a first piston and a first piston rod in the cylinder with the piston rod being connected to the first device and to actuate a second device related to the first device through a second cylinder and a second piston and a second piston rod in the second cylinder with the second piston rod being connected to the second device, the apparatus comprising a valve including a casing provided with a first circular chamber therein and a circular groove in the wall of the first chamber and a second chamber separated from the first chamber by a partition provided with an aperture therein and provided with a first opening in communication with the first chamber and a second opening in communication with the first chamber and a third opening in communication with the first chamber and a fourth opening in communication with the first chamber and a plunger including a circular head of one diameter and a circular section of a smaller diameter than the head positioned in the first chamber and provided with a first longitudinally disposed recess therein extending inwardly from one end thereof and a second longitudinally disposed recess extending inwardly from the other end thereof and of smaller diameter than the first recess and merging with the first recess to form a shoulder at the merger location and a piston disposed in the aperture in the partition and provided with a slot intermediate its ends and stop means on the free end of the section of the plunger and a circular sleeve slidably mounted on the section of the plunger and a first resilient means disposed in the first recess in the plunger and bearing against the shoulder in the plunger and the casing and urging the plunger toward the partition and a second resilient means bearing against the head of the plunger and the sleeve and urging the sleeve toward the stop means, a pump, a reservoir in communication with the pump, and manually operable control means in communication with the pump and the first and fourth openings in the casing, fluid under a predetermined pressure flowing through the first opening and out the second opening to actuate the first device upon the control means being moved to one position and upon reaching the predetermined pressure fluid in the second chamber moving the piston toward the first chamber with the piston moving the plunger against the first resilient means to bring the third opening into communication with the fourth opening allowing fluid to move out of the rod end of the second cylinder through the third and fourth openings to the reservoir and fluid flowing from the second opening into the head end of the second cylinder to actuate the second device and fluid flowing through the fourth opening allowing the first resilient means to move the plunger against the partition and the fluid moving the sleeve toward the head of the plunger against the pressure of the second resilient means and flowing to the rod end of the second cylinder to actuate the second device in the opposite direction and fluid from the head end of the second cylinder flowing into the second opening through the first opening to the reservoir and fluid from the first cylinder flowing through the second opening and the first opening through the control means to the reservoir allowing the first device to be moved in the opposite direction upon the control means being moved to a second position.

References Cited in the file of this patent UNITED STATES PATENTS 2,593,039 Livers et a1. Apr. 15, 1952