US2336351A - Means for adjusting press gibs - Google Patents

Description

vDec. i, 1943., P. E. FLOWERS 2,336,351

MEANS FOR ADJUSTING PRESS GIBS Filed April 29, 1940 ELL. 4 A? /8 2s w my Tog? P 01 E. rmwms ATTORNEYS wear.

patented Dec. 7, i943 S'E'TES .aru FFlC V omens roa anms'rn'vo muss ems Application April 29,1949, Serial No. 332,178 it on. (or. sos s) The present invention relates in hydraulic presses and more particularly to mechanism for guiding the platen during its excursions between the head and the bed of the press.

Fydraulic presses are usually provided with a heavy framework which carries the actuating unit of the press at the top, and mechanical power is transmitted from this unit to the platen platen and therefore form a U shaped recess 'along two opposite edges of the platen which embrace the projecting U shaped portions of the compression members.

The platen and the gibs secured thereto reciprocate continuously during the 'operation ofthe press and the wear between the working surface of each gib and the adjacent compression memher is usually taken up by removing shims from under each gib, depending on the amount of However, it will be apparent that the adjustment obtained in this manner is crude since the adjustment is not obtained gradually and continuously, but rather abruptly as determined by the thickness of the shims. For example, if one shim were to be removed from under each gib the platen may still be too loose within its guideways, but if two shims were re-= moved the platen would be too tight and would bind. When the necessary amount of adjust ment is in terms of a few thousendths of an inch rather than the whole thickness of a shim an adjustment obtained by removing shims is not altogether satisfactory. v

The primary object of the present invention is to provide an improved structure by which an accurate adjustment of the gibs can be made with respect to the compression members of the press, and in particular to provide an improved structure by which the tightness with which the platen slides over the compression members can be adjusted without the use of shims. A still further object is to provide an improved means for adjustably spacing the gib and the press from the platen and for locking the gib in the adjusted position in order accurately to control and to maintain the control of the sliding fit with which the platen is guided along the compression members.

In the prior art it has been customary to bolt the gibs to the platen and to arrange these bolts in a single vertical line down through the middle of each gib in order to secure the gib to the platen. In the event that the gib is fairly wide, it is apparent that a single line of bolts does not give the proper amount of adjustment over the entire width of the gib. In accordance with another feature of my invention, I arrange theimproved spacing and locking means in a staggered relation over the entire width, as well as length of the gib so that proper adjustment may be obtained not only in a vertical direction over each gib, but also in a horizontal direction thereby providing the proper snugness of fit over the entire bearing surface between-the gib and the adjacent compression member.

The above objectives are carried out in brief by discarding the shims referred to hereinbefore and, instead, employing a screw member for spacing the gib from the compression member and maintaining this spacing effect by employing a locking screw contained within the screw member. The arrangement is such that before any adjustment can be made, the locking screw must first be loosened and then the spacing adjustment made, after which the locking screw is tightened so as to make the adjustment permanent. By staggering the spacing and locking screws throughout the entire area of the gib, not only is it possible to obtain a uniform spacing thruout the opposed surfaces of the gib and the adjacent compression member, but also a nonuniform spacing, if desiredwhich provides inthe compression member.

show the details of the improved spacing and locking screw and. the manner in which it openates to give a snug sliding fit between the gib and the compression member.

Figure 4 is a sectional view taken along line 4-4 in Figure 2 and considerably enlarged to show the operation of the wrenches employed in connection with the improved spacing and locking screw.

Referring to the drawing, numeral I designates a heavy block of metal which constitutes the head of the hydraulic press. This head is supported on the bed 2 of the press by means of two or more compression members 3 of angular configuration, and which usually surround and conceal a number of heavy strain rods. These rods pass up through the head and terminate in nuts 4. At the lower ends, the rods pass through the bed 2 and through the end portions of a bottom truss I, finally terminating in nuts 6.1

The head I carries any suitable form of hydraulic cylinder (not shown) containing a piston which is actuated by a pump of any suitable and well-known character (not shown), for example, a variable delivery rotary pump operated by an electric motor and in which the delivery is controlled by an ordinary shift ring (not shown). The plunger of the cylinder is designated I and the lower end thereof carries a platen 8. The platen is provided with a rabbeted portion 9 at each of its vertical comers. The platen is adapted to slide upwardly and downwardly between the compression members 3 and, on its downward or working stroke contacts with a die I0, which is secured to the bed of the press by means of bolts II.

During operation, a sheet of metal is placed on the die member ID and subjected to pressure by the platen 8 which either forms or cuts the metal to any desired shape, depending on the configuration of the lower surface of the platen. The downward and upward excursions are controlled by the shift ring of the pump either automatically or by an operator. In order accurately to control the points of contact between the lower surface of the platen and the metal work piece positioned on the die I0, it is necessary to control the manner in which the platen approaches the work piece. For this reason the platen is guided during its working and also during its upward stroke by the compression members.

The inner corner of the outside surface and compression members are beveled or chamfered at approximately 45 as indicated by the refer-- ence character I2 (Figure 3). A gib I3 is also .bolted to the platen 8. These gibs extend along each vertical edge of the platen and are positioned in the rabbet groove as shown in Figure 3. The gibs are usually made of case-hardened steel and of rectangular configuration, with a length greater than the width so as to extend the entire length of the platen. The edge of each gib adjacentthe beveled edge of the compression member is chamfered or beveled to an angle complementary of the angle of the compression member. -As the compression member is beveled at 45 the gib has a similar bevel.

The bolts by which the ,gib is secured to the platen member are shown more clearly in Figures 3 and 4. Each gib is provided with a large countersunk opening I3a which terminates in a threaded portion of smaller diameter, indicated at I4. This opening receives a large screw member I having a round head, a shoulder l6, and terminates in a threaded portion I! which rests against the lower fiat surface of the rabbeted portion 9. The head of the screw is provided with a hexagonal opening I 8.

Directly under the last mentioned opening there is a threaded opening in the platen which receives the shank of a screw I9, the head 29 of which is of slightly smaller diameter than the distance between the opposite fiat surfaces of the hexagonal opening I8. The head '20 of the smaller screw I9 is also preferably provided with a countersunk opening 2| of hexagonal configuration.

It will be noted from Figure 3 that the axes of the screws I5 and I9 coincide, and the position of this axis with respect to the gib and the platen and the distance between the axis and the inner edge of the platen are such as to leave a small space indicated at 22 between the gib and the side of the rabbeted portion which is shown vertical in Figure 3. It will be further noted that the screw l5 has been tightened and therefore bears against that portion of the rabbeted surface 9 which is shown horizontal in Figure 3, leaving The manner in which the spacing 9 is accurately controlled and maintained will be clear from a consideration of Figure 4. The hexagonal opening 2| of the bolt I9 is adapted to receive the hexagonal end portion indicated at 24 of the wrench 25. This wrench may be fabricated of hexagonal stock having the proper size snugly to fit the opening 2| and bent as indicated at 29 to form a handle. A special wrench 21, also formed of a piece of hexagonal stock, is adapted to be received by the hexagonal opening I8 of the screw I5. The wrench 21 has a round opening which is sufliciently large to permit the wrench 25 to be inserted and rotated therein. A handle 28 is secured to the wrench 21 as indicated in Figure 4.

In making the proper adjustment of the gib with respect of the platen, the lock screw I9 is first unloosened by turning the wrench 25 countar-clockwise (Figure 4), after which the wrench 21 is turned in such a direction as to give the required spacing 23 betwen the gib and the platen. This is usually determined by the amount of friction exercised at the beveled surface l2, and indicated by the load on the pump. When the proper spacing has been obtained to provide the required snugness of the sliding fit between the gib and the platen the wrench 24 is turned clockwise to lock the screw I5 rigidly in the adjusted position.

An analysis of the compression forces exercised between screws I5 and I9 Will show that until the lock screw I9 has been loosened so as to remove its head 20 from the shoulder, it is impossible to rotate the screw I5 in either direction. Consequently, assuming that the proper fit has been obtained at the beveled surface I2, or in other words, the proper amount of spacing 23, this adjustment is rigidly maintained by the screw I5 as long as the locking screw I9 is tight.

From the foregoing, it is evident that I have separated the operation of obtaining the proper fit at the bevel l2 into two functions, namely, the adjustment function which is exercised solely by the screw I5 and the maintenance of this adjustment by the locking screw I9. It is further apparent that the screws I5 and I9 may have difierent coarseness or fineness of thread to perform their individual function in the optimum degree.

While the combined adjusting and locking screw structure may be arranged as units in a single vertical line extending down the middle of each gib it, I prefer to stagger these structures over the entire width aswell as the entire length of each gib. Due to the fact that the screw it serves as a spacing member and bears against the platen, any one of these screws can also constitute a fulcrum about which the gib can be swung depending on the relative positions of the remaining screws I5. Consequently, the beveled edge of the gib is adapted to be swung outwardly and inwardly due to the fulcrum eflects of any line of bolts in order to introduce still further variations of adjustment and greater accuracy in the sliding fit between the gib and the compression member.

It will also be evident from Figure 4 that the spacing adjustment at 23 may be had simultaneously with the locking adjustment due to the manner in which the wrenches 2B, 28 can be manipulated. There is no necessity for shims between the gib and the platen and, furthermore, the spacing 23 can be controlled as accurately as may be desired depending on the fineness of the threads i4 and the angular movement through which the wrench handle 28 is turned.

This fineness and gradualness of adjustment is so pronounced that the same pressure may be brought to bear throughout the entire beveled surfaces which contact, so that the guiding effect of the gib is exercised not only equally by all of Y the compression members, but also equally throughout each beveled surface of each compression member.

It will be understood that I desire to comprehend within my invention such modifications as some within the scope of the claims and the invention.

Having thus fully described my invention, what 1 claim as new and desire to secure by Letters Patent, is:

1. In combination, a reciprocatory element and a guiding gib therefor, means for respectively spacing and locking the gib to said element, said means comprising an adjustable spacing member secured to the gib and bearing against the element, and a locking member extending through said spacing member for maintaining the spacing obtained by the adjustable spacing members.

2. In combination, a reciprocatory element and a guiding g'ib therefor, means for adjustably spacing and locking the gib to said element, said means comprising a hollow spacing screw threaded in the gib and bearing against the element, and a locking screw extending through said hollow spacing screw and threaded in the element.

3. The combination of a press having a press platen an a guideway for guiding said platen with a plate for slidably engaging said guideway, and means comprising a pair of screws, one screw being contained within the other for respectively adjustably spacing said plate from said platen and for locking said plate in its adjusted position, thereby controlling the pressure exercised by said plate on said guideway.

4. In combination, the platen of a press and a guiding gib, said gib comprising a plate adapted slidably to engage a guideway on a press, and means comprising a pair of concentrically arranged screws for adjusting the pressure, one of said screws being screwed into said gib and bear ing against the platen, and the other of said screws being screwed into the platen and having its shaft in slidable engagement with the other screw.

5 5. In combination, the platen of a press and a guiding gib, said gib comprising a plate adapted slidably to engage a guid'eway on the press, and means comprising a pair of concentrically arranged screws for respectively controlling the pressure exercised by the, gib on said guideway and for maintaining the adjustment of said screw relative to each other, the outer screw of said pair of screws being screwed into the gib and bearing against the platen and the inner screw of said pair of screws having one-portion of its shaft screwed into the platen and having another portion of its shaft supported by the other screw. 6. In combination, a pair of elements, guiding means for slidably engaging one of saidelements, a plurality of adjusting screws threaded in one of the elements in staggered arrangement and adapted to bear against the surface of the other of the elements, and a plurality of locking screws hearing against the adjusting screws and threaded into the element adjacent the. element which receives the adjusting screws, said adjusting screws and said locking screws being arranged concentrically with respect to each other. so '7. In combination, a pair of elements, means for securing said elements together and permitting adjustment between the surfaces of said elements, said means comprising a shouldered bore in one ofthe elements, the bore of smaller diameterbeing threaded, an adjusting screw with a threaded shank being adapted to be received by said threaded bore portion, said screw having a shouldered bore of smooth surface, a headed locking screw in the last-mentioned bore, the head of 40 the locking screw bearing againstthe shoulder of the bore, and said locking screw having a portion which is threaded into the element adjacent the element containing the adjusting screw.

8. In combination, a pair of metal elements, means for securing said elements together, said means comprising an adjusting machine screw threaded in one of the metal elements and adapted to bear against the surface of the other of the elements and a locking machine screw surrounded by said adjusting machine screw and bearing against the'adjusting screw, said locking screw being threaded into the element adjacent the element which receives the adjusting screw.

9. In combination, a reciprocatory element and a guiding gib therefor, means for respectively spacing and locking the gib to said element, said means comprising an adjustable spacing member secured to the gib and bearing directly against the element, and the locking member extending through said spacing member for maintaining the spacing obtained by the adjustable spacing members. i

10. In combination, a reciprocatory element and a guiding gib therefor, means for adjustably spacing and locking the gib to said element, said means including a hollow spacing screw threaded in the gib and bearing directly against the element, and a locking screw extending through said hollow spacing screw and threaded in the ele- 70 ment.

PAUL E. FLOWERS.

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