US1636488A - Hydraulic unit - Google Patents

Description

- July- 1927' .1. s. REYNOLDS HYDRAULIC UNIT Filed June '7, 1924 5 Sheets-Sheet 1 11V VENTOR July 19-, 1927.

J. s. REYNOLDS HYDRAULIC UNIT Filed June '7. 1924 3 Sheets-Sheet 2 S v R D y 0 L E 7. a N W N M m H n w. v. w fi M Wk D M\ MN mm .t Nu I 1 I 4 2 Q wm 0m W I F 5x mm ll I W W H W N s Mb 5 m l I I 11k vv mv 3 n M N m m H w 3 \1 v GM 1 .vw m 0.. H m l k. r L i uw Y 7 J. 5. REYNOLDS HYDRAULIC UNIT 7 M Filed June 1924 3 Sheets-Sheet. 3

A TTORNEY' Patented July 19, 1927.

UNITE!) STATES.

PATENT OFFICE.

JOY S. REYNOLDS, OF SAN FRANCISCO, CALIFORNIA, ASSIGNOR OF ONE-HALF '10 CHARLES A. BALCOM, OF SAN FRANCISCO, CALIFORNIA.

HYDRAULIC UNIT.

Application filed June 7,

The present invention is an improved unit for accumulation and regulation of liquid pressure. Thi invention contemplates a self-contained unit, for interposition on a circulation system, adapted to accumulate a desired initial working pressure, and to govern the de ree of pressure, selectively, when same is applied to a work line.

lVhile the invention is applicable to other uses, it is hereinafter described as applied to the operation of liquid controlled brakes on an automobile, deriving power from any suitable source in the mechanism, preferably from the power take-01f of the transmission.

Certain details of the assembly shown in the accompanying drawings are not claimed per se in this application, but are made the subject matter of other applications (two) filed on even date herewith. 3

The objects of this invention include:

(1) The combination, in a self-contained form, of a reservoir, pump, automatic cutout, and control valve, so arranged as to obviate the necessity of packing because of the fact that any leakage from any of the working parts of the system will be directly to the source of supply,

(2) The provision of a unit of the character described, so constructed that but two pipe connections are necessary to be made to said unit, one to the accumulation tank, and

the other to the work. Liquid passes alter- -p nately in different directions through said pipes during different phases of operation. This minimizes the amount of required-pipmg. q

(3) The provision of a unitary container for liquid and for accumulation and regulation members, so constructed that the pump valves and control valve may be withdrawn from the exterior without disconnection or disturbance of the container. This results in economy of manufacture in machine op erations and assembly.

Other objects will appear as tion proceeds.

In this specification and the annexed drawings, the invention is illustratedin. the form considered to be the best, but it is to be understood that the invention is not lim ited to such form because it may be embodied in other forms, and it is also to be this descripe 1924. Serial No. 718,630.

understood that in and by the claims following the description it is desired to cover the invention in whatever form it may be embodied.

y In the accompanying three sheets of drawings:

Figure 1 is a top plan View of my unit;

Fig. 2 is an elevation of my uniton the end of which power is applied;

Fig. 3 is a bottom plan View of said unit;

Fig. 4 is a section taken on the line IV IV-of Fig. 2;

' Fig. 5 is a section taken on line VV of Figs. 1 and 1; and

Fig. 6 is a section taken on line VI-VI of Fig. 3.

Referring to the drawings, the numeral 1 indicates, in its entirety, my pressure accumulating and regulating unit. This unit serves as a reservoir for liquid and also a housing for all moving parts of the system.

Power is applied to my unit through a shaft 2, which, in this case, represents the power take-01f shaft of an automobile, the unit 1 being attached to the said power take-off housing as by screwsthrough holes 3 in a flange 4, Fig. 2.

Any suitable source of power will operate the unit hereinafter described, and while said unit is of particular utility in automobilrbraking, it is useful for other puroses.

The shaft 2 extends into a chamber 6 within the unit 1. A'disc 7 secured to shaft 2', Figs. 4 and 6, carries a pin 8 which is eccentric to said shaft. Freely mounted, on said pin 8 is a roller 9.

Thus, each rotation of shaft 2 raises and lowers the roller 9 as indicated'in dotted lines. This movement is used to depress a piston 11, Fig. 4:, slidable in a bore 12 in unit 1. This piston is returned by a spring 13 which bears at one end against the shoulder 14, and at the other end againsta flange '16 on piston 11. The piston 11 serves as a pump, liquid being drawn from chamber 6 into bore 12 through an intake passage 17, Fig. 4, on the upstroke of said piston, unseating a check valve 18, guided by pins 19, quadrilaterally disposed in a plug21. The valve 18 isurged to seat by a spring 22. The downstroke of piston 11 unseats v a similar check valve 18 and forces said liquid through a discharge passage 23 communicating with a passage 24, Figs. 3 and 5, leading to a line check valve 18". The unseating of this valve 18 by the pump 11 forces liquid through a passage 26 in a nipple connecting member 27. This nipple is connected as by a union 28 to a pipe 29 leading to a pressure tank 31. r

A quantity of air is trapped and compressed in tank 31 by the introduction of liquid, furnishing an expansive medium for forcing said liquid back through pipe 29,

passage 26,- to a passage 32, Figs. 3 and 6.

As all work performed on the hydraulic circulation system, of which my unit is a part, will be supplied from tank 31-, an automatic cut-out for pump 11, which is responsive to pressure fluctuation in said tank, must be provided.

Therefore, I show, Figs. 3 and *4, a passage 33 connecting passage 32 with a bore 34. The cut-out mechanism is best shown in Fig. 4. This feature of my present disclosure is made the subject matter of a separate application for patent filed on even date herewith At 36 I show a boss on the floor of chamher *6. This boss is bored and tapped as indicated at 37, to receive a bushing 38, and

this bore is reduced at 39 to slidably contain a piston .41.

The piston 41 acts as a valve on each end, the upper end being enlarged and tapered as indicated at 42 to seat on a shoulder 43 in bushing 38, and the lower end of said piston being reduced indiamete'r and tapered to seat on the shoulder 44 at the end of bore 34. The limit of travel of said piston 41 is between said seats.

Slidable in the smaller bore of bushing 38 is a plunger 46, rounded on the end adjacent to piston 41 for contact therewith, and threaded at the opposite end for engagement with a sleeve portion of a member 47. This member 47 is slotted as indicated at 48 to admit therethrough a lever 49, pivoted on apin '51, Figs. 1 and 4, protruding from a boss 52, integral with the unit 1.

This leveris of thethird kind, the fulcrum being at '51 at one end, the work being done at the opposite end and power applied therebetween. The lever is raised by a button 52 urged by a spring 53, which bears at one end against said button and at the other end against plunger 46.

By reason of this structure, a rise in pressure in tank '31 will raise piston :41, plunger 46, and the lever 49 will be raised to the dotted line position shown in Fig. 4, In

order to cause this elevation of lever 49., to

arrest the pumppiston 11 in inoperative positi-on, I provide a finger 54 which is bifurcated and suspended from the roof of chamher 6 and is pivotally mounted in lugs 56.

The finger 54 is normally held in the full line position shown in Fig. 4 by a spring 55 coiled around a bushing 57 surrounding a pin 58 which extends through the lugs 56.

The bore in bushing 57 is eccentric to the periphery thereof in order to afford a means of adjustment of the operative length of finger 54. on bushing 57 to engage one of the bifurcated members of finger 54. This secures any adjustment after it is made.

When lever 49 is raised, due to a rise in pressure, said lever will throw finger 54 to the dotted line position because of the oblique bearing between the abutting portions of lever 49 and finger 54.

When in said dotted line position, a notch 59 in the end of said finger engages the flange 1 6 on piston 11 and prevents further reciprocation thereof until relciasedby the restoration of lever 49 to its initial position.

The finger 54 is positively held in this engagement with piston 11 by the abutment of the end oflever 49 with the flat portion on the side of finger 54 remote from said piston, as clearly shown in dottedlines, F ig. 4.

I will now describe automatic means, re

sponsive to a fall of pressure, for lowering the lever 49, and releasing finger 54 from engagement with piston 11, leaving said piston free to operate.

At '61, Fig. 4, I show a plug threaded at '62 into the roof of chamber 6. This plug 61 is centrally bored to form a guide for a stem 63 integral to the member 47.

At 64, I show a coiled spring hearing at one end against plug '61 and at the opposite end against aflange 66 on member 47. The threaded plug 61 affords a means for adjusting the pressure of spring 64 and predetermining the. degree of pressure a-twhich the cut-out will render the pump inoperative.

Operation.

Assuming that my unit is connected to a power take off housing of an automobile transmission, and that shaft 2 is constantly rotated, the pump 11 will be depressed at each revolution of said shaft and raised by spring 13 until such time as said pump has forced a suflicient quantity of liquid into tank 31 to compress air therein until said pressure, acting on the reduced end of piston 41 is sufficient to overcome the urge of spring 64., slightly raising said piston, introducing pressure to the full piston area, as represented by bore 39, whereupon, (due to this increase of effective area), the piston 4i will immediately move to its upward limit of travel where it seats on shoulder 43.

At 58 I show a lock nut threaded- The piston 41 will be held firmly on its 11 by finger 54 is only possible when said piston is inits lowermost position. Should the action of piston 41 (just described) take place when said piston 11 is in any other position, flange 16 thereon would prevent the movement of finger 54 and lever 49. In order to provide a yieldable element whereby the cut-out action may be delayed until piston 11 reaches its lowermost position, 1 provide spring 53 and button 52.

When pressure raises piston 41, the abutting plunger 46 and member 47 rise therewith. If the parts all assume the full line position shown in Fig. 4, the oblique abutment of lever 49 with finger 54 will at once move said finger to its dotted line position and effect a cut out of thepump.

However, should the piston 11 be up, the flange 16 thereon will prevent said move ment of finger 54, and instead the spring 53 will be compressed as member 47 rises until said piston 11 reaches its downward limit, at which time the'urge of the compressed spring 53 will throw lever 49 and finger 54' to their-dotted line positions, rendering the pump inoperative until pressure subsides to a degree Where pressure admitted through a by-pass 67 from bore 39.to bore 37 is insufficient to overcome the urge of spring 64.

When pressure has subsided to a point Where spring 64 depresses member 47 and piston 41, and also lever 49, thus permitting finger 54 to return to its full line position in response to the urge of spring 55, the pump will resume operation. It will be seen that when the pressure is no longer sufficient to keep the larger end seated, the piston descending seats firmly on the smaller end.

It is obvious that a greater reactive force will be required to unseat the smaller valve, and this fact affords an interval of time and range of pressure between cutting in and cutting out operations.

In Fig. 6, I show the outlet 68 from the unit 1. This communicates with a bore 69 which is a reduced portion of a bore 71. These bores enclose my control valve which is not claimed per se in this application, but is made the subject matter of another application filed on even date herewith. At- 72 I show the entrance to bore 71 of passage 35 through which liquid under pressure is admitted from tank 31.

The function of the control valve is to admit liquid under pressure from tank 31 past a valve seated at 73 to a brake line'connected to outlet 68, and under conditions release said liquid from said brake line by return through passage 68, thence past a valve seated at 75, through a port 74, to the source of supply (chamber 6), thus completing the liquid circuit.

The control valve is manipulated to admit pressure from'tank 31 to the brake line by a pull rod 76 connected at one end to a foot pedal 80, hand lever or the like, and at the opposite end to one end of a spring 77 which isconuected at the opposite end to one end of an elbow lever 78 pivoted at 79 in a bracket 81 on the unit 1. The end 82 of elbow lever 78 remote from spring 77 is designed to depress a plunger 83 slidable in bore 69. This plunger is centrally bored to form a passage 84 communicating with port 74 and forming the valve seat 73. The downward movement of plunger 83 is communicated to a valve 86 secured to a stem 87 integral with avalve 88, which last named valve is thus unseated.

The unseating of this valve releases liquid from a chamber 89 faster than it can be replaced through a passage 91 which connects with passage 35, through passage 92, and ports 93, thus releasing pressure behind a piston 94.

, The cross-sectioned area of piston 94 is greater than that of the seat 73, therefore the valve will be forced from its seat by pressure at 72, and liquid will pass seat 73, through passage 68, to the brake line, until pressure in the brake hue rises to a degree at which the pressure on the inner end of plunger 83,

transmitted through elbow lever' 78, will overcome the urge of spring 77.

When the spring 77 is thus overcome, the stretch of said spring admits the rise of plunger 83. Valve 68 follows the plunger up, being urged to its seat 73 by pressure,

As the stem of and also by. a spring 96. valve 88 is connected to valve 68, it will rise at the same time and seat, preventing further pailsage of liquid from chamber 89.

Pressure is promptly accumulated in chamber 89, through passage 91, ports 93, and passage 92, from passage 35, thereby balancing pressure on the opposite ends of piston 94.'

When so balanced, this piston 94, urged by a spring 97 and the flow of liquid at 72, seats and closes communication between'pressure tank and the brake line connected to passage 68. So long as the tension on spring 77 remains unchanged, the pressure in the brake line acting on plunger 83 will balance the effect of spring 77," and said pressure will be retained in said line, maintaining the brake application.

To effect a release of said brakes, a backward movement of the foot pedal relieves the lUf) only until such time as the pressure in the brake line (acting on the bottom of plunger 83 balances with the remaining tension on spring 77. It will be seen that the release of'pressure on the brakes will be directly proportionate to the releasing movement of the foot pedal by the driver.

The same is true when brakes are applied. A'forward pull on rod 7 6 increases tension of spring 77 and brakes will be applied until pressure in the line balances said tenrich, the degree of said application being vdirectly proportionate to thctravel of the foot pedal.

This makes my invention adaptable to conventional automobile controls, as the action, 're-action and resistance corresponds to that produced by mechanical means.

Another distinct advantage of my invention lies in the fact that any number of wheels or brakes may be served by the brake line without requiring additional effort to operate, as the foot pedal operates only the control valve, the Work being performed hydraulically.

At 98 I show an inspection plate for access to chamber 6.

At 99 I show a plug for the introduction of liquid, 100, for a reserve supply for the pump.

At 101, Fig. 1, I show a safety valve threaded into a boss, 102, Fig. 3, on the floor of chamber 6, and adapted to exhaust into said chamber from the pressure tank 31, being connected with passage 82 by a pas sage 103. Obviously, my unit might be so constructed that the component parts would be associated in such relation that the assembly Would form part of the transmission housing and thus dispense with the reservoir 6. In this case the reserve liquid supply would be the oil in the transmission proper.

I claim:

1. A hydraulic unit for attachment to a source of power comprising a reservoir adapted to contain'liquid and provided with a connection leading to a pressure tank, a pump in said reservoir adapted to force liquid therefrom to said tank, a mechanism in said reservoir, responsive to fluctuat on of pressure in said tank, for intermittently operating said pump from said source of power, said connection provided with an outlet for communication with a work line, and a control-valve in said reservoir and associated with said connection, adapted to regulate the passage of liquid to and from said work line.

2. A hydraulic unit for attachment to a source of power comprising a reservoir adapted to contain liquid and provided with a connection leading to a pressure tank, a pump in said reservoir adapted to force liquid therefrom to said tank, a mechanism in said reservoir, responsive to fluctuation of pressure in said tank, for intermittentiy operating said pump from said source of power, said connection provided with an outlet for communication with a work line, a control valve in said reservoirand asso ciated with said connection, adapted-to regulate the passage of liquid to and from said work line, and av safety valve ins-aid reservoir, said pump, said mechanism, said control valve. and said safety valve so arranged that each will waste within "said reservoir. 3. A hydraulic unit for attachment toa source of power comprising a reservoir adapted to contain liquid and provided with a connection leading to a pressure tank, a pump in said reservoir adapted-to force liquid therefrom to said tank, a mechanism in said reservoir, responsive to fluctuation of pressure in said tank, for intermittently operating said pump from saidsource of power, said connection provided with an outlet for communication with a work line, a control valve in said reservoir and associated with said connection, adapted to regulate the passage of liquid to and from said work line. and manually operated means, operable from without said reservoir, for actuating said control valve. V

4. A hydraulic unit for attachment to a source of power comprising :a reservoir a'dapted'to contain liquid and provided with a connection leading to a pressure tank, a pump in said reservoir adapted to force liquid therefrom to said tank, a mechanism in said reservoir, responsive to fluctuation of pressure in'said tank, for intermittently operating said pump fromsaid sourceof power, said connection provided with an out let for communication with a Work line a control valve in said reservoir and associated with said connection, adapted to reignlate the passage of liquid to and from said work line, manually operated means,'operable from without said reservoir, for actuating said control valve, and a resilient member, interposed between said manual means and said control valve. I I

5. A hydraulic unit for attachment to a source of power comprising a reservoir adapted to contain liquid and provided with a connection leading to a pressure tank, a pump in said reservoir adapted to force liquid therefrom to said tank, mechanism in said reservoir, responsive to fluctuation of pressure in said tank, forintermittentlv operating said pump from said source of power, said connection provided with an outlet for communication with a work line. a control valve in said reservoir and associated with said connect-ion, adapted to regulate the passage of liquid to and from said work line, manually operated means, operable from without said reservoir, for actuating said control valve, and a resilient member, interposed between Said manual means and said control valve, whereby said control valve will be responsive to said manual means in one direction and will be responsive to pressure in said work line in the opposite direction.

6. A hydraulic unit for attachment to a source of power comprising a reservoir adapted to contain liquid and provided with a connection leading to a pressure tank, a pump in said reservoir adapted to force liquid therefrom to said tank, a mechanism in said reservoir, responsive to fluctuation of pressure in said tank, for intermittently operating said pump from said source of power, said connection provided with an outlet :tor communication with a work line, a control valve in said reservoir and associated with said connection, adapted to regulate the passage of liquid to and from said work line, manually operated means, operable from without said reservoir, for actuating said control valve, and a resilient member interposed between said manual means and said control valve, whereby said control valve will be responsive to said manual means in one direction and will be responsive topressure in said work line in a reverse direction until such time as said pressure is equal to the urge of said resilient member. 7

7. A hydraulic unit for attachment to a source of power comprising a reservoir adapted to contain liquid, a pressure tank, a connection between the reservoir and the pressure tank, a pump adapted to force liquid from the reservoir to the tank, mechanism responsive to fluctuation of pressure in the tank for intermittently operating the pump from said source of power, a work line communicating with the said connection, and a control valve between the work line and the connection adapted to permit and regulate the passage of liquid from the tank to the work line and from the work line to the reservoir.

8. A hydraulic unit for supplying a work line with fluid under pressure consisting of a reservoir, a pressure tank, a pump for transferring liquid from the reservoir to the tank, a connection between the tank and the work line, and a manually operable control valve adapted to permit and regulate the passage of liquid from the tank to the work line and from the work line to the reservoir.

In testimony whereof I afiix my signature.

JOY S. REYNOLDS.

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