US3006226A

US3006226A - Bench vise

Info

Publication number: US3006226A
Application number: US761036A
Authority: US
Inventors: John W Poysa
Original assignee: Individual
Current assignee: Individual
Priority date: 1958-09-15
Filing date: 1958-09-15
Publication date: 1961-10-31
Anticipated expiration: 1978-10-31

Description

Oct. 31, 1961 J. w. PoYsA 3,006,226

BENCH vIsE Filed Sept. 15, 1958 3 Sheets-Sheet 1 JOHN W. -POYSA IN VEN TOR.

Wawy/(lm.

A TTORNE Y Oct. 31, 1961 J. w. PoYsA 3,006,226

BENCH VISE 3 Shees-Sheel 2 5 air F/G. 6

Filed sept. 15, 1958 D 10a 7 I3 JOHN W. POYSA INVENTOR.

l//V/ I BY A TTORNE Y J. W. POYSA BENCH VISE Oct. 31, 1961 3 Sheets-Sheet 3 Filed Sept. 15, 1958 INVENTOR.

BY ATTORNEY i JOHN W. POYSA.

United States Patent O 3,006,226 BENCH VISE John W. Poysa, 3001 W. Verdugo Ave., Burbank, Calif. Filed Sept. 15, 1958, Ser. No. 761,036 2 Claims. (Cl. 81-3S) This invention relates to vises and particularly to manually operated vises for holding work items while being subjected to fabricating or repairing operations by hand operated tools.

The do it yourself trend in construction and repair work has created a demand for a vise for the home workship which is of low cost and simple construction, yet rugged and capable of holding large articles such as a wooden board as well as small articles such a nail. The conventional type of vise has a fixed jaw with a base member for attaching the vise to a solid fixture and a movable jaw for gripping and releasing the article to be worked on. Movement of the movable jaw is conventionally obtained by providing it with a screw which engages a nut xed to the body of the lixed jaw or engages threads formed on the body of the xed jaw itself. In the type of vise in which the nut is incorporated in the structure of the xed jaw and solidly secured thereto, one of the disadvantages lassociated with that construction is the difficulty of removing the nut for cleaning, oiling or replacement with a new nut. One of `the objects of the present invention is the provision of a vise in which the nut is securely and internally attached to the fixed jaw and yet is easily removable without disassembly of the `two jaws.

Another disadvantage of many previously known vises is that they have been limited in the size of the work items which may be gripped by the limits of movement of the movable jaw with respect to the fixed jaw. One object of this invention is the provision of a vise with attachments so constructed that they may be mounted on the xed and movable jaws and enable the vise to grip work articles of which the smallest dimension is greater than the maximum span between the movable jaw and the fixed jaw. The vise and attachments of this invention are capable of gripping articles having a dimension between the gripped surfaces greater than the maximum grip of fthe vise itself.

A further object of this invention is to provide a simple attachment which by its construction makes it possible `to securely grip round articles of both small and large diameters and which may be readily and solidly attached to the fixed and movable jaws.

The invention may of course take various forms of embodiment without departure from the essential nature of the invention. The details of construction of a preferred form of vise of this invention is shown in the drawings 4and described in the specification. It is to be understood however, that the invention may take other forms and yet come within the descriptive language of the appended claims.

In the drawings:

FIGURE 1 is a vertical longitudinal sectional view of a vise constructed in accordance with the invention.

FIGURE 2 is a bottom plan sectional view taken along the line 2 2 of FIGURE 1.

FIGURE 3 is a vertical sectional view taken along the line 3--3 of FIGURE l.

FIGURE 4 is a vertical sectional view taken along the line 4 4 of FIGURE 1.

FIGURE 5 is a fragmentary plan sectional view along line 5--5 of FIGURE 3 Showing details of the fixed jaw locking blocks and locking screws.

FIGURE 6 is a side elevational view of an attachment for gripping round articles.

ICC

FIGURE 7 is a vertical sectional view taken along the line 7--7 of FIGURE 6.

FIGURE 8 is a vertical section'al View taken along the line 8-8 of FIGURE 6.

FIGURE 9 is a vertical longitudinal sectional view of the attachment shown in FIGURE 6.

FIGURE 10 is a top plan sectional View taken along line 10-10 of FIGURE 9.

FIGURE l1 is a side elevational view of an attachment for holding articles larger than the maximum span obtainable between the xed and movable jaws.

FIGURE 12 is a top view of the attachment shown in FIGURE l1.

FIGURE 13 is a front view partially broken away to show the method of attachment of the clamping blocks to the top surface of the large article attachment.

FIGURE 14 is a Vertical longitudinal sectional view of this attachment.

FIGURE 15 is a perspective view of a clamping bar of this attachment.

FIGURE 16 is `a perspective View of the nut block.

The vise 11 of this invention has a xed jaw 12 (FIG- URE l) which extends upwardly and forwardly from a lixed body jaw 13 of `generally horizontal cylindrical shape. A horizontal disposed extension 14 projects forwardly from the lowermost portion of the body 13. The jaw, body and extension are preferably one integral piece of steel casting.

The body 13 is horizontally rotatably seated in a manner to be described, upon a circular base 15. This base 1.5 is securable to a work bench 16 or other solid supporting xture, as by bolts 17 with fastening nuts, the bolts projecting into the fixture 16 through apertures 10 in a circular disk 18 which is an integrally formed lower portion of the base 15. This disk 18 extends radially outwardly from a vertically disposed cylindrical central hub 19, of the base 15. The vertical cylindrical rim surface 20 of this hub 19 is provided with an annular recess 26, which presents in vertical cross section a lower horizontal surface or shelf 2S and an inwardly and downwardly inclined conically shaped surface 27, which at its lower edge joins at an acute angle the radially inner edge of the shelf 28.

A lower rounded portion 21V of -the jaw body 13 is formed with a vertically disposed cylindrical cavity 23 with an inside diameter such that it snugly fits over the hub 19. 'Ihe lower portion 21 of the jaw body is also formed with a lapped horizontal nether surface 25 which slidably rotatably engages a top surface 22 of the disk 1S. The top surface 29, of the hub 19, is spaced slightly below the nether surface 30 of the cavity 23, which allows free turning of the body 13 on the hub 19, in a complete circle.

In order to lock the lixed jaw 12 at any position of rotation about the base 15, a locking block 33 and a locking screw 34 on each of two diametrically opposite sides of the rounded portion of the lixed jaw body 13 are used as shown on the drawing .in a vertical sectional View (FIGURE 3) and in a fragmentary plan sectional view (FIGURE 5). The locking block 33 is contoured in such a way that its sloping face 31 and its Vertical face 35 fit closely against the conical surface 27 of the hub 19 and the lower annular portion of the vertical cylindrical surface 20 of the hub.

The body 36 of the locking block 33 is contoured to lit Within a cavity 37 having an arcuate rear wall 38, the cavity extending horizontally radially outwardly from the inner bore surface of cavity 2.3 in the rounded portion 21 of the xed jaw body 13. The locking screw 34 has its locking end 40 set in a socket 42 in the rear surface 39 of the locking block 33. Its threaded end 44 threadedly engages a threaded aperture 45 in the wall 43 of the rounded portion 21 of the fixed jaw body 13. Thus the locking screw 34 may be tightened against the locking'b'lock 33, forcing the locking block 33 against the hub 19 and so locking the fixed jaw 12 in any desired angular position on the base 15. Removal of the locking screws 34 from the wall 43 of the rounded portion 21 of the xed jaw 13, permits the disassembly of the fixed jaw from the base 15.

The body section 13 of the fixed jaw 12* has a central horizontal bore 46 in which is longitudinally slidably mounted a hollow tube or shaft 47. This tube 47 consttitutes a supporting body upon which is integrally mounted a movable jaw 48 which co-operates with the fixed jaw 12in the operation of the vise. The front extension 14 of the body 13- of the fixed jaw 12 is formed with an elongated slot 49 of a width to snugly receive a nut block 50. The bottom wall 74 of the hollow tube 47 is formed with a slot 73 in transverse registry with slot 49.- This slot 73 extends from a point near the front end of the tube 47 slightly more than half of the distance to the rear end of the tube. The nut block is normally held in position in the extension 14 in a Vmanner to be presently explained, with its upper portion projecting upwardly through the

slots

49 and 73 into the chamber of the bore of the tube 47 for engagement with the feed threads on an actuating rod 58 of the vise.

As seen in FIGURE 16, the nut block may be considered as consisting of a body 52, a horizontal rearward extension 53 of the lower portion of the body 52 of the same width as the body 52, a horizontally disposed barrel 56 of the same diameter as the width of the body, and extending from the forward end of the body to within a short distance from the rear end thereof, a neck 56 connecting the barrel and body which is of the saine length as the barrel, and with its side faces inset from the sidevfaces of the body, and with a short rearward extension 53 of its lower portion, terminating in a face 77 flush Iwith the rear face 52 of the body 52. The body, barrel, neck, and extensions of the body and neck are preferably machined from a single integral piece of steel.

TheV extension 53 of the nut block is rounded at its rear end, presenting a sernicircle in horizontal profile, and is formed with a hole 55 for the reception of a fastening screw 54. The upper threaded end of this screw is securable in a threaded hole 54 in an integrally formed web 21 projecting forwardly at an upper level from the forward side of the rounded portion 21 of the fixed jaw body 12, holding the rear end of the nut block against Vertical displacement. This rounded rear end of the nut block extension 53, abuts horizontally a matingly rounded surface 55 in the base portion 21 directly beneath the web 21'.` The nut block is thus locked against horizontal displacement rearwardly.

The front end face of the nut block is formed with a horizontal transverse groove 51 of arcuate vertical cross section which fits snugly against a convexly arcuate ridge 49' formed on a forward face of the extension 14, which face bounds the front end of the slot 49 in this extension, this ridge being shaped to conform to the curve of the groove V51. The rear surface 52 of the nut block body 52 and the rear surface 77 of the rear extension 53 of the neck 56 are also slightly arcuate in vertical cross section about a center which is approximately that of the arcs of the groove 51 and ridge 49. When the fastening screw 54 is removed, the nut block is free to drop downward, its rear end describing a short arc about its front end until the rear end of the neck 56 of the nut block clears theV web 21', whereupon it is free to drop clearof the vise assembly. It is free to be thus disassembled,.however, only when the nut block is not being engaged by the actuating screw of the actuating rod 58 in a mannento be now described.

Within the barrel 56 is pressed an internally threadedV bronze bushing 57. Threaded into the'bronze bushing 57 of the nut block barrel 56 is a matchingly threaded actuating rod 58. The rod 58 is rotatably mounted and fixed against endwise movement at both ends of tube 47 and moves as a unitary part of the movable jaw assembly. Fixed on the forward and unthreaded end 63 of the actuating rod 58 isa ball 59' with a circular anged shoulder 6i). rIhe shoulder 60 is rotatably seated in a circular recess 61 in the front portion 64 of the movable jaw 4S. For smooth rotation of the anged shoulder 60 of the ball 59 a slip washer 63 is inserted between the face 66 of the lianged shoulder 64) and face 65 of the recess 61.

The bore chamber of the tube 47 is'partially closed at its front end by an integrally formed internal ange 47 and at its rear end by a plug 71. The flange 47 and plug 71 are bored at 62 and 67 to provide bearings for the rotation of the rod 58. The forward portion of this rod isof somewhat larger diameter than the rearward portion and is threaded for engagement with the bronze bushing 57. The rearward portion is smooth surfaced, except at its rear end 66, which is threaded.

The actuating rod 58 is restrained from forward movement within the hollow tube 47 by a retaining nut 68 and a retaining nut locknut 69, on this threaded end 66 of the rod 58'. A slip washer 70 is placed between the retaining nut 68 and the rear face of the plug 71, for smooth rotation of the actuating rod 58. The ease of rotation of the actuating rod is determined by the degree to which the retaining nut 68 is tightened upon the threaded rear end 66 of the actuating rod 58.

Rotation of the actuating rod 58 is accomplished by rotation of a crank rod 89 which is snugly, but slidably inserted within bore 9i) centered through the ball 59 of the actuating rod 58. Crank rod balls 91 are pressed on each end of the crank rod 89 to prevent the crank rod 89 from slipping through the bore 9i)y of the ball 59.

Operation of the vise is as follows. Since the actuating rod 58 is threaded internally within the block 50, rotational movement of the actuating rod by means of the crank rod S9 will produce longitudinal movement of the actuating rod with respect to the nut block Sti. Since the nut block is longitudinally xed on the jaw assembly 12, and the actuating rod 58 is longitudinally fixed on the jaw assembly y48, longitudinal movement of the actuating rod 58 with respect to the nut block 50 produces an equal longitudinal movement of the movable jaw 48 -with respect to the xed jaw 12. A clockwise movement of the crank rod S9 in a vertical plane closes the vise jaws in a clamping action, and vice versa.

VYThe bottom face 75 of the front portion of the hollow tube 47 of the movable jaw 48 is plane surfaced. The bore 46 of the fixed jaw 12 is so centered in the fixed jaw body 13 that when the hollow ltube 47 of the movable jaw is inserted in the bore 46, the plane-surface 75 of the hollow tube 47 is held firmly against the plane-surfaced top face 72 of the front extension 14 of the fixed jaw 12. By this construction the movable jaw 48 is firmly held and prevented from a twisting rotation in -a vertical plane with respect to the fixed jaw 12,

The nut block also functions as a stop to limit movement of the movable jaw away from the fixed jaw 12. The slot 73 of the hollow tube 47'is so dimensioned longitudinally that the rear face 76 `of the slot 73 will Contact the rear face 77 of the nut block neck 56, stopping movement of the movable jaw 48 away from the fixed jaw 12 while a substantial area of the forward plane-surfaced bottom face 75 of the hollow tube 47 of the movable jaw `48 is still in contact with the plane-surfaced top face 72 of the front extension 14 of the fixed jaw 12. Thus the front plane-surfaced bottom face 75 of the hollow tube 47 is stopped from extending forward past the lip 78 of the front extension 14 of the fixed jaw 12.

The clamping grip 79 of the movable jaw 43 is at the tip of a relatively narrow curvilinear root or neck 82 on the front portion S6 of the hollow tube 47. The clamping grip 86 of the fixed jaw 12 istat the ti-p of a relatively narrow root or neck 88 on the upper body portion 87 of the fixed jaw 12. By the use of such construction articles shaped for example like a T, may be clamped with the narrow portion between the clamping grips 79 and 80, and with the wide portion disposed beneath the grips between the

roots

82 and 88 of the movable and fixed jaws respectively.

The gripping surfaces S4 and 85 of the

grips

79 and 80 are case hardened in the conventional manner.

The slot 73 in the bottom wall of tube 47 (FIGURE 2) has a narrower rearward portion 73a and a wider forward portion 7317. The forward portion has parallel sided portion 73C between its arcuate contoured ends, which is the length of the nut block vbarrel 56. The width of the rear portion 73a is sufhcient to snugly embrace the inset side surfaces of the neck S6 of the nut block. The width of the wider forward portion is sufficient to allow vertical passage of the barrel of the nut block in the course of its insertion or removal from the chamber of the tube 47. In removing the nut block, the nuts 68 and 69 are first removed and the actuating rod 58 is then turned in the nut block until it is disengaged from the nut block. The rod is then removed from the vise assembly. The movable jaw assembly is then slipped to its extreme rearward position '(if not already in that position) in which the slot portion 73c is directly below the nut block barrel. The nut block is then removed from the vise assembly in the manner which was earlier stated.

FIGURES 6 to l0 show the construction and method of attachment of two

auxiliary jaws

103 and 104 to the vise described in the foregoing part of the specification and shown in FIGURES l to 5 of the drawings. These auxiliary jaws which will be designated as a Whole as attachment A, are for gripping round objects such as pipes, shafts, `and other cylindrical or curvilinear surfaced work articles.

Jaws

103 and 104 are very similar in construction. Jaw 103 is attachable to the fixed jaw 12 of the vise. I aw 104 is attachable to the movable jaw 48. Jaw 103 has 'a body portion 105 from which gripping teeth 106 project forwardly and a pair of anchoring wings 107 project rearwardly. These wings 107 have horizontal straight line lower edges 108 which rest tightly against the upwardly facing surface of the main cylindrical portion 37 of the body 13.

The base body 105 of the auxiliary jaw 103 has a top and rearwardly sloping rounded convex surface 109 (FIGURE 9) vwhich fits tightly against the continuous concave forwardly facing surface 110 of the grip 80, root 88 and top portion 87 of the body 13. The bottom surface 111 of 105 is concavely rounded upwardly, longitudinally centrally of its width at 111:1 to nest solidly upon the convex cylindrical surface of the larger diametered forward end portion 47a of the tube 47 of the front jaw, when the two jaws of the vise are in closed position. FIGURE 6 shows the `dierent diameters of the two end portions 47a and 4'7b of the tube 47. If the two ends of the vise be brought together it is apparent from this FIGURE 6 that the nether surface 1110 would rest solidly upon the rear portion of the surface of 47a.

The wings are dished inwardly to t tightly and solidly against the side surfaces of the root 88 and are flared outwardly -to their lower edges 108 to similarly solidly engage the upper surface of the cylindrical portion 87 of the body of the xed jaw 12. In brief if the auxiliary jaw 103 be moved horizontally rearwardly into the rearmost position sho-wn in FIGURES 6, 9 and l0, one surface or other of the body and wings of the auxiliary jaw abuts solidly, either upwardly, rearwardly, downwardly or laterally, some surface of the jaw 12 and its body 13, leaving it free to move in one direction only, i.e. forwardly, as far as the adjacent contacting walls are concerned.

Movement in that direction is prevented by a pair of spring-urged flat-headed pins 112, which are mounted in small housing bosses 114 integrally formed on the outer sides of the wings, respectively, and which snap into holes 101 respectively so placed in the sides of the neck 88 that they become alined with the pins when the wings have reached their rearmost home position. In this position the wings, and with them the auxiliary jaw bodies and jaw grips are as immovably a part of the Vise main jaw to which they are attached as though they were solidly bolted to that main jaw, and for all operative purposes as solidly as though they were an integral part of the main jaw. And yet they are removable by the simple expedient of pulling the pins 112 away from each other by the fingers of the two hands of the operator and then with the fingers still on the fiat heads of these pins, pulling the auxiliary jaw forwardly toward the front of the vise. In the operative position it will be noticed that the auxiliary jaw is held in position beneath the grip of the main jaw, a relative position made possible by the relatively great height of the grips of the main jaws above the hollow tube or shaft 47 of the movable main jaw 48.

The movable auxiliary jaw 104, while otherwise similar in general shape to the fixed auxiliary jaw 103, has shorter wings 116 longitudinally of the vise and the wings 116 may be spaced slightly closer together at their lower edges than are the wings 107 due to the slightly smaller diameter of the forward portion 47a of the tube 47 of the main movable jaw than that of the top body portion 87 of the main fixed jaw 48. Since the roots 82 and 8S are of the same transverse width7 the spacing of the wings 116 at the location of the pins 117 (corresponding to the pins 112 of the other auxiliary jaw 103) is the same as that of the wings 107. The movable jaw 104 has a body 113, gripping teeth 115, and spring urged pins 117 housed in bosses 113 on the sides of the root 82, which are counterparts of the similar numbers on the fixed jaw. Pins 117 snap into holes 102 in the neck 82. The movable auxiliary jaw 104- also has its surfaces similarly tightly and solidly related to surfaces on the main movable jaw as is true of the fixed auxiliary jaw in the manner already related in describing the fixed auxiliary jaw 103.

The gripping

teeth

106 and 115 of

auxiliary jaws

103 and 104 respectively may be of any conventional or.

desirable type which satisfactorily grip and hold against rotation work items such as pipe and other objects of curvilinear section. The teeth of the auxiliary jaws shown in the drawing of this invention are integral extensions outwardly from the jaw bodies and 113 respectively. The teeth 106 are produced by first machining the outwardly projecting portion of the body 105 to present a plane surface sloping upwardly and outwardly from the transverse axis line 119 o-f the vise to the top surface of the body, a second plane surface sloping downwardly and outwardly from the axis line 119, a horizontal plane nether surface 120 and a vertical plane surface 121 set back from the vertical plane of the axis line 119 extending from the nether surface 120` to the nether surface 111:1 of the body 10S (see FIGURES 6 and 9). A first series of narrow kerfs 122 are then milled in the body 105 extending from the top surface 109 of the body downwardly and outwardly to the axis line 119: a second series of narrow kerfs 123 are then milled in the same planes as the kerfs 122 extending downwardly and inwardly from the axis line 119 to the surfaces 120 and 121. These machining operations leave a set of V-shaped teeth 106 with an obtuse angle of the V at the axis line 119 and the straight line legs of the V extending, one upwardly and outwardly, and the other downwardly and outwardly from this axis line. The teeth have approximately the 'same thickness as the width of the

kerfs

122 and 123.

The teeth of the movable auxiliary jaw are similarly formed, with, however, the teeth in the same planes as the

kerfs

122, and 123 of the teeth of the xed auxiliary jaw, the two sets of teeth being thus interleaved and transversely overlapping each other to provide a very effective and powerful grip on a rounded work article.

FIGURES ll to l show an attachment which will be designated as attachment B, comprising a pair of

auxiliary jaws

139 and 131 for holding articles of greater gripping width than the maximum span of the main jaw grips 79 and Si). Attachment B is especially suited for holding wooden boards, rails, etc. for woodworking operations thereon.

Auxiliary jaw 135 of attachment B has a top work holding plane-surfaced table 132 and a front depending ange or apron 133 integrally formed with the table 132 which when the jaw 13) is in working position on the vise is disposed in front of, and in contact with, the grip 80 of the fixed main jaw of the vise. The auxiliary jaw also has a rear upstanding transverse ilange 134 integrally joined to the table at its rear edge, and a pair of webs 13S spaced apart from each other and integrally formed at their upper edges with the table and at their front edges with the flange 133. These Webs 135 are braced with a transverse vertically disposed block 136, which is integrally joined at its two ends with the inner side faces of the webs 135 and is integrally joined at its uppermost portion with the under surface of the table 132. The block 136 is plane surfaced at its vertical rear face 139 and is concave on its forward face 140 this concave surface 14() beginning at the lower edge of its vertical rear face and terminating at the under surface of the table.

The rear lower portions of the webs 135 are formed with bosses 137 in which are seated spring urged flatheaded pins 138 like the `corresponding bosses and pins in attachment A. rlfhese pins are mounted on the webs in a position adapted for their entry into the holes 101 in the root portion 83 of the main jaw 12. The webs 135 rather snugly embrace the sides of the root 8?, and the concave surface 140 rests solidly upon the top surface of the root 88. The forward end portions of the webs are flared outwardly and upwardly to their upper forward ends where they are joined to the ange 133. The central portion of the flange 133, just under the table, is formed with a rectangularly outlined recess 141 of a vertical width and transverse length to snugly and solidly tightly receive the grip Si) of the main fixed jaw.

The auxiliary jaw 136 is attached to its main jaw for operative purposes by moving the auxiliary jaw downwardly until the plate 132, just to the rear of its ange 133, rests upon the grip 8G of the main jaw and the convex surface 140 of the block 136 rests upon the root SS. The pins 138 are grasped by the fingers of the two hands and pulled apart and then rearwardly until the main grip `80 enters the recess 1141 and solidly engages its wall surfaces and the pins 138 fall into place in the holes 101. The block now solidly engages the back of the root S8 and the arched rear portion of the body of the fixed main jaw. The auxiliary jaw now cannot move appreciably in any direction and becomes a xed part of the main jaw.

The movable auxiliary jaw 131 is formed similarly to the fixed auxiliary jaw 139 with a somewhat shorter table 142, a depending flange 143, an upstanding ange 144, a bracing block 145, a pair of webs 146, and a recess 147 for reception of the grip 79 of the main movable jaw. It is assembled on the main movable jaw in a manner similar to the manner of assembly of the auxiliary fixed jaw on the main ixed jaw.

The flanges y134 and 144 at the outer ends of the tables of the fixed and movable auxiliary jaws respectively serve as work grips for boards or other wooden work articles. In addition to these lianges each of the two tables 132 and 142 is provided with a

movable grip bar

148, 149, respectively which may be secured transversely of the table in any of a plurality of positions. For this purpose each table is formed with a number of rectangular apertures 1511 arranged in pairs, the apertures of each pair being transversely alined across the table. As shown in the drawing, table 132 has three such pairs of apertures and table 142 has two such pairs of apertures. The inner wall of each aperture extends from the table top vertically downwardly for a short distance, then is inclined inwardly toward the center of the vise for a further short distance and again extends vertically downward to the under surface of the table.

The grip bars 14S and 149 are identical in construction. Their length is the same as the width of the table. Each has an inner work-engaging vertical grip face 151 on a vertical leg 152 of the bar, a horizontal table en gaging face 153 on a horizontal leg 154 of the bar, and an end web 15S at each end of the bar. Depending from each bar are a pair of lugs 156, rectangular in cross section, one at each end of the bar. These lugs are spaced to register with the associated apertures and are of a rectangular shape, depth and size to snugly enter these apertures and thereby hold the bar against sliding lateral movement in any direction over the table. Each bar may be selectively secured to the table at the location of any pair of apertures.

To prevent unintended dislodgment of the bars from position on the table, the lugs are shaped on their inner transverse faces to conform to the shape of the apertures l t? and are rounded on their outer transverse faces to facilitate intentional withdrawal or placement of the bars. A bar will not move upwardly in a straight vertical path because of the hook-shaped lower lug end 157, but may be intentionally separated from the table by giving the bar a combined upward and rolling movement with respect to its longitudinal axis and thereafter lifting it from the table.

These bars malte it possible to provide a wide variety of work spans between jaw grips, for engagement with a wide variety of work articles having a wide variation in their grip spans. The maximum span of the auxiliary jaws between

flanges

134 and 144 is far greater than the maximum span of the main jaws, and yet the auxiliary jaws may be adjusted to grip very narrow boards or wooden strips, either between the bars at their innermost positions, or between the depending

flanges

133 and 143.

l claim:

l. ln a bench vise, the combination of: a stationary main jaw assembly, a movable main jaw assembly suitably disposed and related to the stationary main jaw assembly for gripping work objects between the two jaw grips of the two assemblies, an auxiliary stationary jaw assembly attachable to the stationary main jaw assembly, and an auxiliary movable jaw assembly attachable to the movable main jaw assembly, each of said auxiliary jaw assemblies comprising a table, a front ilange depending from said table, a pair of spaced webs depending from said table and extending rearwardly from said ange, a recess being formed at the juncture of said flange with said table and between said webs for snugly receiving therein the jaw grip of the respective main jaw assembly, a block depending from said table and rearwardly displaced with respect to said ilange for supporting said table on said respective main jaw assembly in substantially horizontal position, each of said main jaw assemblies having formed therein oppositely disposed, substantially aligned recesses, and resiliently urged pins carried by each of said webs and engageable in said recesses for holding the auxiliary jaw assembly against movement in one direction, and each of said tables having an upwardly extending auxiliary jaw grip and said auxiliary jaw grips being so disposed for gripping work objects of greater width than can be accommodated between the jaw grips of the two main assemblies.

2. The combination defined in claim l, in which the table of each of the auxiliary jaw assemblies has formed therein a plurality of pairs of vertical apertures arranged transversely of the table; and also includes a cross bar having a pair of pins sized and spaced to t Within said apertures.

References Cited in the le of this patent UNITED STATES PATENTS Stephens Oct. 20, 1874 Stoughton May 2, 1905 Blackmore Aug. 23, 1910 Strand Jan. 16, 1923 Rankin Mar. 14, 1933 Germany Oct. 1, 1921