US2486707A - Valve and actuating mechanism for fluid motors - Google Patents

Description

Nov. 1, 1949.

J. E. ELKINGTON VALVE AND ACTUATING MECHANISM FOR FLUID MOTORS Filed June 18, 1945 3 Sheets-Sheet 1 Noml, 1949. E K N 2,486,707

VALVE AND ACTUATING MECHANISM FOR FLUID MOTORS INVENTOR. JAMES, E .E Kma-roN Nov, 1,. 1949. J. E. ELKENGTON ,4

VALVE AND AC'I'UATING MECHANISM FOR FLUID MOTORS Filed June 18, 1945 3 Shets-Sheet 3 J: a 53 r -11- 7 1 4Q 47 INVENTOR. JAMES F. .t\ \N6TON Patented Nov. 1 1949 UNITED STATES PATENT OFFICE VALVE A'ND ACTUATING MECHA- NlSM FOR FLUID MOTORS James E. Elking'ton, SanFrancisco, Calif.

Application June .18, 1945, Serial No. 600,089

.3 Claims. .1

This invention relates to a 'dishwashing machine and particularly to a hydraulic actuator or prime mover for reciprocating a dish tray moving rack in and through the washing zone of said machine; said actuator being made to reciprocate by hydraulic pressure in alternating cycles.

An object of the invention is to provide a hydraulic actuator which includes a plunger made to reciprocate by applying hydraulic pressure in alternating cycles to opposite faces of the plunger thru the instrumentality of a valve timer synchronized to operate with the plunger and to control its operation.

In the accompanying three sheets of drawings:

Fig. 1 is a side elevation of a dish washing machine constructed in accordance with my .invention, showing my hydraulic reciprocater -operatively applied thereto.

Fig. 2 is an end elevation of Fig.

Fig. 3 is a plan view of the rack (for reciprocating the dish trays) having my reciprocator applied thereto.

Fig. 4 is a cross-section taken thru one side of the dish washing machine showing the relationship of the slide rack, trays and tray guides.

Fig. 5 is a longitudinal section of a hydraulic actuator or prime mover constructed in accordance with my invention, illustrated in its application to a slide rack on a dishwashing machine, the plunger of the actuator being secured to the rack while the actuator mechanism is 'fixed on One end of the washing machine struc-' ture.

Fig. 6 is a front view of the valve chamber i with the operative mechanism removed.

Fig. 7 is an enlarged cross-section taken thru the valve chamber on the line of Fig. *5.

Fig. 8 is a view of the rear face of the actuator valve.

Fig. 9 is a cross-section taken through Fig.8 0n the line 99.

Fig. 10 is a rview of the front face of the actuator valve.

Fig. 11 is .a front elevation of the valve chamber showing the operative mechanism mounted therein.

Fig. 12 is a side elevation of the yoke for actuating the valve.

In detail the construction illustrated in .the drawings comprises in Figs. 1 and 2 a .dish washing machine which in its entirety is designated bythe numeral 38'. This dish washing machine includes, in addition to the necessary structural frame Work, a water tank 3|, .fiuid spray pipes 32,.a fluid pump 33 :and a motor '34, a reciprocating rack 35 mounted over the tank 31 and between the spray pipes 32 for :moving trays 36 of dishes and the like thru the washing zone :on the parallel guides 31 which extend longitudinally thru the machine.

'The dirty dishes or other articles to be washed are placed by hand in trays 36 and the loaded traysare placed on the entrant endlof guides 31. The guides 3! are 'tormed'of spaced complementary angle bars and beneath :said guides the reciprocating rack 85, see Fig. 3, is slidably mounted. The rack 35 :is formed of parallel bars 33 connected by transverse members 6. The bars 38 rest and slide'upon brackets 39mounted on opposite sides of the machine as shown in Fi .4.

The inside face of each of the bars 38 is provided,

at spaced intervals between the ends thereof, with counterweighted gpawls i!) pivotally mounted thereon. The upper end 411 .of each pawl 40 is adapted toengage ribs .or serrations (not shown) on the under side of the dish trays 36 for the purpose of intermittently advancing said .dish trays thru the washing process from the entrant end .of the tray guides .31 to the discharge end thereof. The rack 3:5 is reciprocated on a -horizontal plane in the manner to be hereinafter described. When the;r,acl.35 sis reciprocated forwardly toward the discharge end of the washing machine the upper end 44 of each ;pawl engages the dish trays 36 and advances them, with an intermittent movement, along the tray guides 31. .On the return stroke of the rack 35 the pivoted pawls -40 disengage from the dish trays but automatically swing upwardly into contact with the vdish trays upon .the start of the forward stroke :of the rack 35.

The type of rack 35 .hereinabove described for advancing the dish "trays thru the wash zone is only one of many types of similar racks which parallel endless belts could be actuated intermittently by my prime mover for moving the dish trays thru the machine. It is to be understood that while I have developed the prime mover particularly for its use .on a .dish washing machine, that the reciprocative impulses developed by it could be applied .to ,or utilizedon many-other machines of a type and kind needing a reciprocative movement in some phase of their operations.

Spaced nested cylinders 2 .and 3 are mounted on the base I and are closed at the end-opposite to the base I by a cap 1. The cap 1 is secured to the base I' by rods, welding or otherwise.

The cap I is drilled centrally with the axis of the cylinders 2 and 3 to provide a bore in which a shaft 8 is slidably confined. The outer end of the shaft 8 is fixed to the cross member 6 of the rack, while the inner end of the shaft 8, within the inner cylinder 3, has a plunger or piston 9 mounted thereon.

The end of the shaft 8 where it is secured to plunger 9 is drilled axially at II]. This open bore I8 is closed by a hollow plug H. A stem I2 is slidably confined in the plug II and the end of the stem within the bore has an annular shoulder l3 there around to limit the movement of the stem in one direction. The opposite end of the stem I2 extends through a hole in the base I into the reservoir 4 where it has attached thereto a yoke M which is related mechanically to the valve structure to be hereinafter described. The valve structure consists of the valve plate I1, see Figs. 8, 9 and 10. The valve I1 is pivotally mounted at its bottom end on a pin l8 fixed in the chamber 4. The valve l1 has a flat face l9 which is operatively mounted in relation to three ports 2!], 2| and 23, on one wall of the chamber 4. The port 28 communicates directly with the inner cylinder 3, Figs. and 6, while the port 2| communicates with the space between the inner and outer cylinders 2 and 3 and through the port 22 with the interior of the inner cylinder at a point near the outer end thereof, see Fig. 5. Midway between the ports 28 and 21 is the port 23 which latter port is an exhaust or relief port, through which spent fluid pressure from cylinder 3 flows to a collection tank 43 on the base of the machine 30. In order to communicate the exhaust port 23, alternately, with the ports 20 and 2|, the flat face E9 of the valve I1 is recessed at 24, the length of said groove being sufiicient to connect the ports" 20 and 23 or 2! and 23, depending upon'the position of the valve I 1.

F.uid under pressure is developed by a rotary pump 44 connected to the motor 34. The fluid pressure is delivered thru a line 25 to the valve chamber 4, while the spent fluid is returned from said chamber through a line 45 to the tank 43. A pipe 26 supplies fluid from the tank 43 to the pump 4 The valve is mechanically swung back and forth by the yoke l4. The yoke l4 has a slot 46 therein. A pin 41 has one end slidably confined in the slot 46 while the head 48 of the pin is confined in an oval slot 49 in the valve l1. A pair of radially disposed pins 50 and 5| are arranged on diametrically opposite sides of the center pin 41, each of pins 50 and 5| having an eyelet 52 confined on the center pin 41. The outer end of each of the pins 50 and 5| is confined in a recess 53 in the inner wall of the chamber 4. An expansion spring 54 is mounted around each of the pins 50 and 5|. The yoke I4 is provided with ears 55 and 56' on one face thereof, said ears lying on opposite sides of the eyelets 52 on the center pin 41.

In the operation of the device hydraulic pressure is delivered to the chamber 4 from the pump 44. The valve i1 being positioned as shown in Figs. 5 and 11, fluid pressure passes from the chamber 4, thru port 2|] and into the inboard end of the cylinder 3, causing the plunger to move outwardly in the direction of the arrows, thereby forcing the inert oil on the outboard side of the plunger to be moved into and thru the port 22 and discharge port 23 to the collection sump 43.

When the plunger reaches the extreme limit of its outboard movement, the stem 12 exerts a pull on the yoke l4, the ears of which engage the eyelets 52 on the center pin 41 forcing the pins 50 and 5| from the off-center position shown in Figs. 5 and 11 to an opposite off-center position. The movement of the pins 50 and 51 from one offcenter position to the other, causes the springs 54 to be momentarily compressed up to the time said pins 50 and 5| reach an aligned dead center position. Immediately after passing the deadcenter position, the pent up pressure of the compressed springs is released causing the pins 50 and 5| to snap rapidly out and in, so doing, causing the valve H to move rapidly from one operating position to the other. The spaced compression springs and 56 located in the lower periphery of the chamber 4 are designed to deaden the impact of the valve l1 when snapping from one position to the other. The change of position of the valve closes the port 20 and opens the port 2 I. Immediately fluid pressure starts feeding out thru the port 2|, thru the space between cylinders 2 and 3, and thru the port 22 into the outboard end of the inner cylinder 2 to work against the outboard face of the plunger 9 causing it to move inwardly. Oil on the inboard side of the plunger is discharged out thru the port 20 and discharge port 23. When the plunger 9 reaches the inboard end of its stroke the yoke on the stem l2 exerts a pull on the center pin 41 and causes it to snap the valve over from one position to the other, thus immediately reversing the direction of flow of the fluid pressure and the plunger 9. The alternate reversal of directional movement of the plunger continues automatically as long as there is fluid pressure directed into the apparatus.

The valve I1 is only one form of device for synchronizing the movement of the plunger and timing the delivery of fluid pressure to opposite faces of the plunger and it is to be understood the invention contemplates that other types and kinds of valve timers might be used in place of the specific form of device illustrated and described herein.

Having thus described this invention, what I claim and desire to secure by Letters Patent is: 1. Hydraulic apparatus comprising a cylinder; a piston in said cylinder; a source of liquid under pressure; conduit means extending between said cylinder and source; a valve interposed in said conduit means to control the application of hydraulic pressure from said source to opposite faces of the piston; said valve having an arcuate surface; pivot means for said valve eccentrically disposed with respect to said surface; a link member interconnecting said piston and valve to oscillate said valve about said pivot means in timed relation with the piston stroke and thereby control the application of hydraulic pressure at intermittent intervals to opposite faces of the piston for reciprocating said piston; and a spring substantially radially disposed with respect to said surface stressed by said valve in a terminal position thereof serving to accelerate the movement of the valve at the commencement of its oscillation.

2. Hydraulic apparatus comprising a cylinder; a piston in said cylinder; a source of liquid under pressure; conduit means extending between said cylinder and source; a valve interposed in said conduit means to control the application of hydraulic pressure from said source to opposite faces of the piston; said valve having an arcuate surface; pivot means for said valve eccentrically disposed with respect to said surface; a link member interconnecting said piston and valve to oscillate said valve about said pivot means in timed relation with the piston stroke and thereby control the application of hydraulic pressure at intermittent intervals to opposite faces of the piston for reciprocating said piston; an overcenter spring imparting a snap action to said valve in its oscillating movements; and a spring substantially radially disposed with respect to said surface stressed by said valve in a terminal position thereof serving to accelerate the movement of the valve at the commencement of its oscillation.

3. Hydraulic apparatus comprising a cylinder; a piston in said cylinder; a source of liquid under pressure; conduit means extending between said cylinder and source; a valve interposed in said conduit means to control the application of hydraulic pressure from said source to opposite faces of the piston; said valve having an arcuate surface; pivot means for said valve eccentrically disposed with respect to said surface; a link member interconnecting said piston and valve to oscillate said valve about said pivot means in timed relation with the piston stroke and thereby control the application of hydraulic pressure at intermittent intervals to opposite 6 faces of the piston for reciprocating said piston; and a pair of springs substantially radially disposed with respect to said surface alternately stressed by said valve in the terminal positions thereof serving to accelerate the movement of the valve at the commencement of each stroke of its oscillation.

JAMES E. ELKINGTON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 196,958 Weir Nov. 6, 1877 1,766,988 Farr June 24, 1930 1,770,931 Lathrop Jul 22, 1930 1,993,154 Elkington Mar. 5, 1935 2,103,001 Evans et a1 Dec. 21, 1937 2,235,544 Wold Mar. 18, 1941 2,265,306 Orshansky Dec. 9, 1941 2,269,423 Barks et al Jan. 13, 1942 FOREIGN PATENTS Number Country Date 16,606/34 Australia Jan. 4, 1935

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