US2254613A - Hydraulic press - Google Patents

Description

Sept. 2, 1941. l. F. MATTHYssE HYDRAULIC RESS Filed Allg. l5, 1938 INVENTOR. ERICK MYSSE /////l,lY

ATroRgEY.

Patented Sept. 2, 1941 UNITED STATES PATENT OFFICE HYDRAULIC PRESS Irving Frederick Matthysse, New York, N. Y.

Application August 13, 1938, Serial No. 224,820

3 Claims.

'I'he present invention relates to a portable hydraulic press in which the pump and reserve oil reservoir are combined with the press itself as a single assembly. A press of this type is Very useful in the electrical utility industry for use in conjunction with electrical connectors for making connections in transmission and distribution lines, both underground and overhead. In addition, it may be used for a Variety of other purposes-as a punch, as. a cable or bolt cutter, etc. Its usefulness is by no means limited to the electrical industry; it may be used for any one of the numerous applications which might call for a small portable press.

An efficient method of making electrical connections in electrical cables is to insert the ends of the cable into the ends of a close fitting tube and indent the tube onto the cable ends. This method has been used widely Where the cable connections have been made as factory assemblies and heavy stationary presses could be used to indent the connectors onto the cables. How.- ever, Where connections had to be made in transmission and distribution systems in the field, presses light enough to be conveniently used Were not available. The Weight of the press is of special importance Where connections must be made on overhead lines. A man Working on a pole top must have a light easily handled device to operate. In order to be readily used the press should Weigh less than ten pounds.

Therefore, one object of the present invention is to provide a complete, self-contained press, which is portable and which can be easily carried by a linesman to the tcp of a pole.

In making electrical connections underground, such connections must many times be made in small manholes or hand holes. Because of the lack of space in such hand holes any tool which must be used therein must be small and compact. Similarly, Where installations must be made overhead on live lines, it is important that the tool should not be as long as the clearance between phases. If the tool were that long, a careless lineman might short the phases with the tool and a serious accident might result.

Another object of this invention, therefore, is to provide a short, compact tool.

For each size of cable there is an indentation with an optimum depth of impression for efficient gripping of the conductor. The proper depth may be determined for each cable size by experimentation. Once this value is found, it is desirable that all indentations on the same cable sie be of the same depth. It is quite diicult for the lineman on a pole top or a splicer in an underground vault to know exactly how deep the punch has penetrated into the connector. Therefore, an automatic arrangement is necessary to relieve the pressure exerted by the tool when the punch has penetrated to the proper depth.

Another object of this invention, therefore, is to obtain a press whereby the length of travel of the punch is automatically determined.

Because of the awkward positions in which linemen or splicers, overhead or underground, mustV Work with this device, and the repeated indentations they must make with it, it must be easily operated. This requires a considerable mechanical advantage and a high eiciency. In order to reduce the relatively large losses due to friction, a hydraulically operated tool was found to be most efcient. In addition, the mechanical advantage of the tool can be easily regulated in a hydraulic device.

Another object of this invention, therefore, is to provide a hand actuated device which can be operated with a minimum of fatigue.

In order for a hydraulic press to function properly, air must be excluded from the portion containing fluid which is under pressure. Inasmuch as air is compressible, if it were to get into the pressure chamber, it would act as a lcushion and prevent 'the pressure from building up quickly. Unlike other hydraulic devices, where the pump is either a separate unit, or is permanently located so that the air cannot get past the fluid reservoir, this invention combines both pump and press and is designed to be used in any position and at any angle. To accomplish this, I have devised a follow-up piston which makes the entire hydraulic system a closed system, so that air cannot penetrate into either the pressure chamber or the reservoir.

Therefore, a still further object of my invention is to obtain a device which can be operated in any position and any angle without air getting into the pressure chamber and acting as a cushion.

In joining cables on end into a continuous length it must be possible to remove the tool after the connection has been made. This may be accomplished in a variety of Ways. The Working head of the tool may have a replaceable die which can be slipped out in order to permit removal of this tool from the joined conductor. Another Way is to make the working head in the form of a hook.

Another object of my invention, therefore, is

to obtain a device that can be readilyrem'oved from the conductor after the connection has been completed. i

After the indentation Is made and the hydraulic pressure released, it is desirable that the punch automatically recede into the pressure chamber. 'I'his eliminates the necessity of manually forcing the punch back, which is an awkward and time consuming operation.

Still another object, therefore, of my invention, is to provide a punch which will automatically recede when the fluid pressure in the pressure chamber is released.

Very often connections must be made in live electrical cables. In such cases it is desirable to work with an insulated tool. other object of my invention is to provide a portable hydraulic press that can be readily insulated.

Because of the awkward positions and cramped quarters in which my tool must often be used, I have made the working head rotatable to various angles. Therefore, another object of my invention is to provide a portable hydraulic press with a rotatable working head. v

My hydraulic tool is designed to exert pressures up to approximately 18,000`pounds. However, if pressures in excess of this figure were built up within the tool by continued pumping, damage might result to the packing of the tool or even to the metal parts. Another object of my invention, therefore, is to provide an automatic relief valve which will relieve the fluid pressure in the pressure chamber when excessive values are built up therein. This is the same valve whichcontrols the depth of penetration of the punch as previously described.

I accomplish these and other objects and obtain my new results as will be apparent from the device described in the following description, particularly pointed out in the attached claims, and illustrated in the accompanying drawing, in which:

Fig. 1 is a sectional, axial view through my A device.

Fig. 2 is a top view of the same.

Fig. 3 is a side view.

Fig. 4 is a partial, sectional view taken along the line 4-4 in Fig. l.

In the drawing, reference numeral I designates the portable pump, reservoir and press, illustrated in section in Fig. 1. The unique bellows-like action is accomplished by an integral handle II, a pivoted lever I2, a body I3, and a head I4.

A holding die I5, semi-cylindrically shaped as at I 3 to support the cable I1, enclosed in the Therefore, an-

mounted in the body I3. The piston is inserted into a cylindricaly recess 3|, provided with a shoulder 32, upon which is seated the packing washer 33, the packing 34, all retained in position around the piston by the packing nut 35 threaded into the mouth of the recess.

'I'he head of the piston is C shaped as at 33, engaging the piston pin 31, integrally attached to the lever I2, by means of a pair of bracket plates 38. A fulcrum pin 39, supported by fulcrum bracket 40, preferably formed integrally with the body I3, is carried by bracket plates 38, permitting the lever I2 to be pivotally mounted ony the body. The bracket plates 38 are shaped to form the stop 4I to engage the body.

The cylindrical chamber 3| to which the piston is closely fitted, terminates in a passageway 43 for allowing the oil to follow the piston in its outward motion. Transversely extending at the termination ofthe passageway 43 is a passage 44 into which is inserted vthe small ball valve 45, supported by shoulder 46 formed into the passageway, leading to channel 41, connecting the oil reservoir 48. An oil screen fllter 43, is placed against the opening into the reservoir to keep foreign matter from interfering with the operation of the ball valves.

Passageway 44 terminates in a channel 53,

forming shoulder 5I, carrying large ball valve sleeve I8, forming partA of the connector, not w. shown, is provided with shoulders I8, riding infr grooves 28, of the head I4. A retaining screw 2I, threadedly engaging tapped hole 22, holds spring 23, forced against ball 24, which in turn is forced against an indentation 24A, in the wall of the holding die I 5, to prevent the die from longitudinal movement with respect to the grooves 28.

'I'he indentation in the cable enclosed sleeve I8, is' accomplished by a ram 25 propelled under the oil pressure, to which is flttedan impression die 28 shaped with a projection 2 1 in the form desired. A die set-screw 23 holds the impression die to the face of the ram.

'Ihe unique bellows-like action of the device is accomplished by designing the compressing pis- 52. Valve spring 53 is made up with three sections, one section 54 of small diameter for engaging small ball valve 45 for keeping it shut when the tool is operated in positions where the force of gravity will not cause the ball to drop into the proper position.

Middle section 55 is of a diameter sufficient to maintain longitudinally the three sections in axial alignment within the passageway. The remaining section 56, is of a diameter to engage properly large ball valve 52. This novelly wound spring, it has been found, will align the spring in the passageway to properly engage the ball valves without jamming between valves and seats. Channel 50 contains spring r51 for seating ball valve 52, supported by spring retainer 58, threadedly engaging the end of channel 50.

The oil flowing through channel 50 enters the ram chamber 80, formed in the body I3 by the cylindrical` recess 6I, into which the ram 25 is slidablymoveable. The ram is provided with peripherally formed shoulders 82, supporting the ram packing 63, in turn covered by ram spring washer 64 and compressed by ram nut 85. threadedly engaging the end of the ram and provided with a central recess 68 substantially thesame diameter as a central recess 51 within the ram itself, extending longitudinally to a point near the ram face58 and terminating in the to the ram. Within the central bore 31 of the ram is housed the ram return spring 1I, carried about pin 12, having a flat head 13 integral therewith for supporting the spring 1I. 'I'he other end of the spring is supported on the head 55A of the ram nut 65, which is apertured as at 35B to permit the free flow of the oil therethrough. 'I'he pin 12 may be milled withtwo flat surfaces 12A to facilitate assembly of the ram to the body, I3.

The remaining end of the pin is longitudinally slotted as at 14 to permit the flow of oil therethrough (s ee Fig. 4) and threadedly engages a tapped channel 15 forming an oil return. VA guide screw 18 projecting through a tapped aper.

ture 11 in the side of head I4. provides a longitudinal guide for ram 25 by riding on slot 11A.

The head |4 of the press is internally threaded as at 18 engaging the externally threaded section 19 of the body |3. 'Ihe head and body are rotatably mounted thereon with head stop screw 80 inserted through a tapped aperture 8| in the head for engaging the two sides of a 90 degree cut-out (not shown) in the wall 82 of the body |3. A frictional movement of the head throug 90 degrees is thus provided.

In Fig. 4, the sectional view shown is normal to that shown in Fig. 1. Two attachments are there illustrated, namely a pressure relief or overload valve 90 and a manual release valve 9|. the latter of which controls the channel 15, the oil return. Connecting with channel is passageway 96 provided with a beveled shoulder 92 on which is seated the cone shaped valve 93, of stem 94, to which the manual release knob 95 is integrally connected.

The valve stem has a narrowed section 96, to

permit the oil to flow around it when the valve 93 is lifted oi its seat 92. The transverse recess 91 houses the valve stem 94, to which a channel 98 connects, permitting the oil to ow into the reservoir 48. In the upper portion of recess 99, are provided shoulders |00 into which is fitted valve packing |0|. A packing nut |02, externally threaded at |03, is provided with a tapped bore |04 permitting the upper threaded section |05 of the valve stem 94 to be threadedly inserted. The packing nut is inserted into the upper tapped bore |06 of recess 99 to compress the packing, rendering the valve leak-proof. A stop screw |01 is inserted into the packing nut through transverse threaded passage |08, to prevent the valve stem 94 from being completely removed. This is accomplished by allowing the narrowed section |09 of the stem to abut the stop screw |01 in its open position. When the stop screw |01 is completely inserted, it acts as a lock to prevent any movement of the valve stem.

The overload valve 90, comprises a cylindrical section |20, loosely fitted in the oil channel 2| having a cone-shaped valve |22 engaging the seat |23 extending therefrom and a guide stem |24 loosely tted in a tubular section |25 extending from nut |26 externally threaded at |21 into the threaded terminal |26 of the oil channel |2|. Apertures |29 in nut |26 allow the oil to ow through the oil channel |2| into the reservoir 48. A pressure spring |30 is supported at one end by nut |26 and the other end engages the shoulder |3| of the cylindrical valve section |20 forcing the valve |22 against seat |23. The tubular handle is hollow and is externally threaded at one end |40, to engage the internally threaded bore |4| of the reservoir cap |42. The body |3 is externally threaded to receive the threaded cap |42. Within the hollow handle is a filler cap |43 having a projecting threaded stem |44, for threadedly closing the threaded end |45 of vthe follow-up hollow piston |46. A washer |41, prevents leakage between the cap |43 and piston |46. The head |48 slidably fits the internal cylindrical reservoir 48, and on shoulders |49, is provided with packing compressed by packing nut |5|. Follow-up spring |52 forces the follow-up piston into the reservoir 48 against pin |53 inserted into holes |54 in handle Il, catching a coil of the remaining end of the spring.

` on the lines.

' chambers.

f load pressure.

Operaton The outward movement of piston 30 forces oil from the reservoir 48 past ball valve 46 into the piston chamber 3|. Downward movement of the piston forces the oil out of the piston chamber into the ram chamber 60, opening ball valve 52 against the action of its spring 51. The ram moves forward by the added volume of oil. This action continues until the desired indentation or tool action is completed.

When the tool is to be reset, the oil is released from the ram chamber by manually operating the release knob 95 which lifts the valve 93 from i its seat 92 permitting the ram return spring, 1|, to draw back ram 25, thus forcing the oil to flow from the ram chamber 60 back into the reservoir 48, through slots 14, channel 15 and 98.

In the event the pressure 'in the ram chamber- 60 exceeds the rated pressure. relief valve .opens against spring |30 to permit the oil to escape back into the reservoir, reducing the pressure to the capacity of spring |30. 'I'his action is automatic.

To avoid the entrance of air into the press, which might accumulate in4 the piston chamber 30 and effectively prevent the rapid pressure build-up, the follow up piston |46 is provided. It follows the reduction in volume in the reser-v voir under action of spring |52, permitting the oil to be withdrawn intcthe vpiston and ram Any type of expanding and contracting chamber for excluding air from the oil reservoir may be used, such as a flexible diaphragm, chamber or bellows.

A layer of insulating material |55 completely covers all exposed surfaces, as shown, to prevent electrical shock or short circuit. Shield |56, is provided as an additional precaution.

While the shoulder, 16A limits the depth of penetration permitting the oil pressure to automatically build up until the overload valve operates, the invention contemplates devices in which a lever connected with the ram, will trip valve 90 releasing the oil, without building up to the over- Furthermore, while a single piston is shown, a double acting piston, or a double piston may be used to accelerate the action. And whereas the handle is shown integral with the body, it may be made pivoted, as at 39, and connected with its own piston.

It can thus be readily seen' that I have accomplished all the foregoing objects of my invention. .Instead of a separate press and oil reservoir, hitherfore used for the foregoing purpose, I have combined them into a single assembly. The weight of the press described, and shown in the drawing, is approximately ten pounds-light. enough for any operator. It is small enough to t into any box or handhole where it is desired to compress a connector to a conductor. It is compactly and eiilciently designed to permit ease of operation from any position or angle, the bellows-like action facilitating manual operation of the lever and handle. It is short enough to permit clearance between phases Set screws and stops determine the maximum penetration, and in addition permit the head to rotate with respect to the handle, where required. An important result obtained is the complete exclusion of all air, which might result in loss of eiiiciency. The device is operable from any position or any angle without air leakage, and may be installed on the cable and readily removed therefrom after the connection has been made. After the properv pressure or depth of penetration has been reached, the punch will automatically recede. p

I have'thus described my invention, but I desire it understood that it is not coniined to the particular forms or uses shown and described, the same being merely illustrative, and that the invention may be carried out in other ways without departing from the spirit of my invention, and, therefore, I claim broadly the rightto employ all equivalent instrumentalities coming within the scope of the appended claims, and by 'means of which, objectsof my invention are at- Patent is as follows:

1. A hydraulic press comprising a body having an oil reservoir, a ram, a chamber therefor, a piston for forcing the oil from the reservoir into head rotatably mounted on said body for supporting the object to be pressed and attached to said ramA and rotatable therewith as a unit, independently of said body and withoutloosening therefrom. l

2. A hydraulic press comprising a body having an foil reservoir, a ram, a chamber therefor, a piston for forcing the oil from the reservoir into the ram chamber for propelling the ram, and a head rotatably mounted on said body for supporting the object to be pressed and having stop the ram chamber for propelling the ram, and a meansthereon for terminating the movement of the head with respect to the body, a predetermined amount in either' direction.

3. A hydraulic press comprising a body having an oil reservoir, a ram, a chamber therefor, a piston for forcing the oil from the reservoir into the ram chamber for propelling the ram; a spring for automatically returning the ram to its starting position and assembled to said ram and removable from thebody as an assembled unit; and a head for supporting the object to be pressed.

IRVING FREDERICK MAI'I'HYSSE'.l

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