Tool Kit for Watch Strap Replacement

The present invention relates to a work table and tool kit for removing and attaching a watch strap, band and the like to the lugs of a watch case.

At the present time, wrist watch straps, bands and bracelets are secured to the spaced projecting lugs on a wrist watch case by means of a spring bar connector. The spring bar connector customarily employed comprises a tubular housing within which is mounted a pair of pintles that are spring urged outwardly. This type of connector has found almost universal acceptance in the field. Typically, the connector is inserted in a loop or other passage at each end of the watch strap. To attach the strap to the watch lugs, one projecting pintle of the connector is inserted in a hole provided in each lug and then the other pintle is first retracted into the tubular housing, aligned with the hole in the other lug and released so that the pintle is urged into the hole by spring action. Retraction of the projecting pintle is usually accomplished by pushing the end of the pintle inwardly until it is retracted sufficiently to align the spring bar in proper position relative to the lug holes. The overall operation of inserting the spring bar connector in position between the lugs of the watch case is a tedious one and is often quite difficult because of the shape and contour of the watch and the limited space available. The projecting pintles of the connector are also quite small and difficult to retract without some type of tool. Of course, removal of the end attachment is likewise fraught with difficulties.

In the past, tools of various types have been used in attempts to facilitate removal or attachment of the watch strap having spring bar type connectors. For example, the consumer who purchases a replacement watch strap has frequently used the blade of a penknife to effect removal of the old watch strap and attachment of the new strap. This technique, of course, presents certain safety hazards and is not entirely satisfactory. Jewelers on the other hand, have employed a special tool for this purpose. The tool typically has a pin on one end for watch lugs having through-holes, i.e. extending completely through the lug, and a forked-portion on the other end for watch case lugs having holes extending only partially therethrough. Removal of the watch strap in the former instance is accomplished simply by inserting the pin of the tool into the through-hole of one lug and pushing the end of the spring bar connector to retract its spring-urged pintle sufficiently to release the connector from that lug. The connector and strap are then easily freed from the other lug. In the latter instance, the forked-portion of the tool is inserted between one of the watch case lugs and the pintle of the spring bar connector, straddling the spring bar connector. The forked end is tapered and portions thereof contact an annular shoulder typically formed on the retractable pintle of the connector. When the forked-end is pushed onto the connector, the tapered portion compresses the retractable pintle slightly to partially disengage it from the lug hole. The tool must then be twisted or pushed to free the connector and strap from that lug. The connector and strap are then easily freed from the other lug.

There is still recognized a need to provide a device or other tool with which the spring bar connector of a watch strap can be easily removed from and fastened to the spaced lugs of a watch case, especially by unskilled individuals.

The Linnbaum U.S. Pat. No. 246,522 issued Aug. 30, 1881 and the Flip U.S. Pat. No 2,679,776 issued June 1, 1954 disclose horological tools apparently intended for uses other than removing a spring bar connector from the watch case lugs. The Niel U.S. Pat. No. 2,700,910 issued Feb. 1, 1955 discloses a plier-like tool having a bifurcated lower jaw with tapered claws for effecting removal of a sheet metal spring nut from a stud without damaging either component.

It is an object of the present invention to provide a work table adapted for assisting in the removal and attachment of a watch strap connector of the spring bar type between the spaced inner lug surfaces of a watch case.

It is another object of the invention to provide a tool kit which can be used by unskilled retail clerks, consumers and others to easily remove and attach a watch strap or band with spring bar type connectors.

A typical work table of the invention includes a working surface, preferably horizontally oriented, carrying watch support pad means thereon. The watch support pad means is suitably sized to accommodate various sizes and shapes of watches and is made of a soft, nonabrasive material which will not harm the watch finish when the watch is placed on the pad means for strap or band removal as described hereinbelow. The work table also includes as an important feature a pintle-compressing member typically in the form of an upright plate-like member having a first side wall and a second side wall, preferably with an elongated recess therein, connected together at one end by a narrow end wall of selected thickness. The elongated recess provided in the second side wall extends toward and terminates at the end wall for purposes which will become evident. The thickness of the end wall of the plate-like member is selected to compress a pintle of the connector when the plate-like member is interposed between the facing inner lug surfaces with the first side wall immediately adjacent one inner lug surface in partial overlapping relation thereto such that a portion of the adjacent lug surface extends past the end wall and with the second side wall in spaced, facing relation to the other inner lug surface with the spring bar connector therebetween. In this arrangement, one (free) pintle of the connector is engaged in the recess in the second wall of the pintle-compressing member while the other pintle is engaged against the facing inner lug surface. Attachment of the free pintle of the watch strap connector to the free inner lug surface adjacent the first side wall is achieved simply by sliding the pintle along the elongated recess in the second side wall toward and past the end wall of the pintle-compressing member such that the pintle will expand and enter the mating lug hole located in the prealigned free inner lug surface when the end wall is passed. Attachment of the watch strap connector is thus completed since the other pintle has already been engaged with the mating lug hole located in the other inner lug surface.

The work table also preferably includes one or more storage compartments for storing one or more strap removal/attachment tools when not in use. Detent means associated with the work table extends into the storage compartments to releasably hold the tools therein.

The tool kit of the invention includes the work table described hereinabove and one or more removal/attachment tools housed in storage compartments of the work table. Each tool usually is in the form of a shaft having handle means at one end and a bifurcated, chisel-shaped blade at the other end. The blade may be straight or angled. Preferably, the handle means includes a first groove at the inner end adapted to engage the detent means extending into the storage compartment of the work table to releasably hold the tool in the compartment and a second groove at the outer, exposed end to facilitate manual removal of the tool from the storage compartment. The tools are useful in removing watch strap connectors in which the spring-urged pintles have an annular shoulder near their ends and the majority of spring bar type connectors used today have such pintles. Removal of a watch strap is accomplished by placing the watch on the work table with the watch crystal located on the watch support pad to expose the backside of the watch. While holding the watch on the pad, the dismantling tool is simply placed over the spring bar connector (straddling the connector) at one end thereof with the flat first surface of the tool blade adjacent the inner surface of one of the watch case lugs and the tapered second side adjacent the shoulder of the spring-urged pintle engaged to that lug. The dismantling tool is then simply pushed toward the watch support pad of the work table causing the tapered second surface of the tool blade to exert an axial camming action on the pintle shoulder away from the lug and causing sufficient retraction of the pintle from the lug to effect release. With one of the spring-urged pintles released, the other is easily freed to remove the watch strap from the watch case lugs.

The tools are also useful in attaching metal type bands or bracelets that may be difficult to assemble using the pintle-compressing member of the work table. Attachment of such bands or bracelets with the tools is generally the reverse procedure from removal.

A cover member is also preferably provided as part of the tool kit to engage over the work table to provide a neat, compact device. The cover member preferably is configured to capture the exposed handle means of the tools stored in the compartments of the work table to prevent accidental tool loss.

FIG. 1 is a top elevational view of a typical prior art wristwatch.

FIG. 2 is a top elevational view of a typical prior art spring bar connector.

FIG. 3 is a perspective view of the tool kit.

FIG. 4 is a close-up perspective view of the support wall of the work table.

FIG. 5 is a cross-sectional view showing a detent spring extending into the storage compartments in the work table to engage the inner groove in the tool handle.

FIG. 6 is a perspective view of a tool with a straight chisel-shaped blade.

FIGS. 7a and 7b are enlarged elevational views of the straight chisel-shaped blade of the tool.

FIGS. 8a through 8d are perspective views showing the chisel-shaped blades of the four tools of FIG. 3.

FIGS. 9a and 9b are enlarged elevational views of the curved chisel-shaped blade of another tool.

FIGS. 10a and 10b are perspective views showing steps in the removal of a watch strap with a tool.

FIGS. 11a and 11b are perspective views showing steps in the attachment of a watch strap with the work table member.

FIG. 12 is a perspective view showing attachment of a watch band with a tool having an angled chisel-shaped blade.

FIG. 13 is a partial perspective view showing how the curved blade of a tool is used to compress the end of the spring bar connector for strap attachment.

Referring to FIGS. 1 and 2, there are shown a conventional wristwatch 2 and spring bar connector 4, respectively. The wristwatch comprises a case or bezel 2a having spaced, facing lugs 2b between which the spring bar connector is inserted. Each lug includes a blind hole 2c extending from the inner lug surface 2d toward the outer lug surface 2e (see FIG. 10a). Of course, if desired, the holes may extend through each lug as is the case with some wristwatches. The wristwatch is illustrated as having a dial plate 2f which in combination with the rotating hands 2g, 2h, 2j provide time information. Of course, the other types of time display schemes may be employed; for example, time could be displayed in digital form using well known electrooptical displays such as liquid crystal displays or in hybrid digital-analog form using electro-optical displays alone or in conjunction with a dial plate and rotating hands.

The spring bar connector is shown as comprising a tubular housing 4a formed of bent sheet metal and spring-urged pintles 4b inserted into opposite ends of the housing. Each pintle typically includes an outer small-diameter pin 4c with ends 4f for engagement in the holes 2c of the watch case lugs and an inner, larger-diameter shaft 4d which slides within the tubular housing. An annular shoulder 4e is formed between the outer pin and inner shaft. Although not shown, a coil spring or other suitable spring means is placed in the tubular housing between the pintles 4b to urge them outwardly into engagement with the lug holes and at the same time allow them to be at least partially retracted into the tubular housing during strap removal or attachment. Of course, the spring bar connector 4 is usually received within a loop formed at the end of the watch strap, band or bracelet 6, for example, as shown in FIG. 10a. As used hereinafter, "strap" is intended to include straps, bands, bracelets and the like made of leather, plastic, metal and other materials.

The tool kit of the invention includes the work table 8 and tools 10-13 shown in FIG. 3. The work table member comprises a rectangular base 8a of metal, plastic or other suitable material having a top working surface 8b. Disposed in a recess in the working surface is a watch support pad 8c on which the wristwatch is placed during strap removal or attachment as described herebelow. The watch support pad is made of soft nonabrasive material such as rubber, vinyl, felt and the like which will not mar or otherwise damage the finish of the watch when placed thereon as described below. Although the watch support pad 8c is shown as having a circular cross-section, it is apparent that other shapes and sizes may be employed as well to accommodate the range of watch sizes and shapes in use today. Machined, molded or otherwise formed in the work table preferably at one end 8d thereof are four or other suitable number of cylindrical storage compartments 8e adapted to receive the tools. The tools are held in position in the storage compartments by means of a spring detent 7 extending inside the compartments (FIG. 5) acting on an inner groove provided in the handle of each dismantling tool as described hereinafter. Of course, other types of spring detents can be employed.

Supported above the working surface 8b by support blocks 8f and 8g is pintle-compressing member 9 (FIG. 4) in the form of a small metal plate having a first side wall 9a and a second side wall 9b with a recess 9d held against the end of support block 8g for example by interference fit in slot 8h in support block 8f or by adhesive, screws and the like. It is apparent that a portion of the first side wall 9a extends past support 8g to provide room for positioning one of the watch case lugs thereagainst as described hereinbelow. The side walls 9a and 9b are connected together by an end wall 9c of selected thickness at which the elongated recess 9d in the second side wall terminates as shown. The dimensions of the metal plate 9 typically are 0.750 inch in length, and 0.250 inch in width with the recess being 0.012 inch in depth and 0.125 inch long and 0.110 inch wide. Thickness of the pintle-compressing plate refers to the distance between the first side wall and second side wall and in the embodiment described is selected as 0.012 inch.

The work table 8 is small and compact in size, for example, the base 8a is only 4.75 inches long and 2.75 inches wide so that the work table can be conveniently employed in association with a counter-top display such as those used to display wristwatches for sale in retail and drug stores. The work table may, if desired, be permanently affixed to the counter-top display in a customer-accessible location to allow customers to conveniently replace their own watch straps. Or, a non-slip pad 8m may be attached to the bottom of the base, FIG. 5 to minimize unwanted movement of the work table. Of course, other shapes and sizes of work tables may be used.

FIGS. 6 and 7a-7b illustrate one tool useful in conjunction with the watch support pad on the work table for strap replacement. The tool 10 comprises a shaft 10a having a handle 10b at one end and a bifurcated, chisel-shaped blade 10c at the other end. The handle has inner circumferential groove 10d adapted to be engaged by spring detent 7 in the storage compartment of the work table and outer circumferential groove 10e provided to facilitate removal of the tool from the compartment by providing a tactile gripping area on the exposed end of the tool. The blade includes on one side a flat, first surface 10f and on the other a tapered or bevelled second surface 10g and a third tapered or bevelled surface 10h, both of which intersect a flat, third surface 10j. Slot 10k extends upwardly from the tip of blade to in effect define a pair of claws each with a flat first surface and a tapered second surface. The width of the slot 10k is selected to allow the tool to straddle the spring bar connector 4 as shown in FIG. 10a with the flat first surface 10f adjacent the inner face 2d of one of the watch case lugs 2b and with the tapered second surface 10g adjacent the shoulder 4e of the spring-urged pintle engaged to that lug. Removal of the pintle from the watch case lug is effected simply by placing the wristwatch on the work table with the watch crystal 2k supported on the watch support pad 8c and while holding the watch on the pad, pushing the dismantling tool toward the pad. During movement of the tool past the strap connector, the tapered second surface 10g exerts a camming action on the shoulder 4e of the pintle in an axial direction away from the adjacent lug to cause the pintle to retract out of the lug hole and thus be released, FIGS. 10a and 10b. Should the blade of the tool contact the watch support pad, it will not be harmed. The watch strap and connector are then easily pulled from the other lug to effect total disengagement from the watch case.

FIGS. 8a-8d show the chisel-shaped blades of all four tools 10-13 for direct comparison. It is seen that there are provided two tools 10 and 11 with straight blades 10a and 11a which differ from another merely in the width of the blade and blade slot to permit different sized spring bar connectors to be gripped. Two tools 12 and 13 are provided with curved blades 12a and 13a which differ from one another in blade width and blade slot width as well as in the severity of curvature imparted to the blade. FIGS. 9a and 9b show the curved blade 13a of tool 13 enlarged. The selection of blade sizes and shapes is of course determined by considering the different sizes and shapes of watch cases, spring bar connectors and straps to be attached or removed. By providing multiple tools with different blades, the user can select the particular tool most suitable for his or her watch. The tools 10-13 are typically made of hardened and tempered steel suitably machined and bent, although other materials may of course be used.

Attachment of the replacement watch strap is illustrated in FIGS. 11a and 11b. The first step, FIG. 11a, involves inserting the pin 4c of the right-hand spring-urged pintle 4b into the right-hand lug hole and placing the pin of the left-hand (free) pintle in the recess 9d of the second side wall 9b of the pintle-compressing member. Then, the left-hand (free) lug is positioned adjacent the first side wall 9a in partially overlapping relation such that a portion of the inner lug surface extends longitudinally past the end wall 9c, FIG. 11b. In effect, this step partially compresses the pintles of the spring bar connector as will be appreciated from FIG. 11b. The thickness of the end wall 9c is preselected to provide sufficient compression of the pintles to allow the strap connector to fit between the watch case lugs; e.g. a thickness of 0.012 inch has been foundsatisfactory. The watch strap connector is then simply pushed toward the end wall 9c to slide the free pintle along the slot 9d and past end wall 9c, the slot guiding the pintle movement. As soon as the pintle passes the end wall 9c, it expands against that portion of the inner lug surface extending past the end wall and into engagement therewith. If the hole of the free lug is properly aligned, the pintle will snap directly into the hole. If there is some misalignment, it may be necessary to lift or depress that end of strap slightly to move the pin of the free pintle into engagement with the lug hole. One side of strap attachment is thus completed since the other pintle has already been engaged in the mating lug hole located in the other inner lug surface. Preferably, the watch lugs 2b are supported on the top surface of support block 8d during the attachment operation just described. Total strap attachment is completed by repeating the above described steps with the other end of the watch strap.

As depicted in FIG. 12, the tools described hereinabove are also useful in attaching a metal type band or bracelet having a spring bar connector to the watch case lugs 2b. Use of the tool in lieu of the pintle-compressing member of the work table may be necessary as a result of the configuration of the metal band and/or the case in the vicinity of the attachment end. Attachment is effected by selecting the tool 10, 11, 12 or 13 which is most suitable for the band and case used, e.g. tool 13 in FIG. 12. Then, one end of the spring bar connector is inserted into the hole in one lug, e.g. the rear lug in FIG. 12. The other end of the spring bar connector is then positioned into the slot 13k in the blade 13a of the tool (FIG. 13) with the pintle end 4f engaging tapered or bevelled surface 13h and the end of the spring bar connector is compressed by pushing the tool axially toward the spring bar connector. The watch band is then pivoted toward its mating lug until the compressed end of the spring bar connector is guided into alignment with the hole in the lug. The tool is then removed by retaining the spring bar end of the watch strap with one finger while lifting the tool upwardly away from the pintle, allowing the pintle to snap outwardly into engagement with its mating lug hole. Attachment of the watch band in this manner is best performed on the work table with the watch crystal resting on the work support pad 8c.

It is thus seen that the tool kit of the invention satisfies the long felt need for means enabling simplified watch strap replacement, including strap removal and attachment, by unskilled retail clerks and consumers.

A cover member 14 may also be used in conjunction with the components already mentioned as shown in FIG. 3 to provide a compact and neat device. The cover member may be molded plastic bearing an appropriate legend, instructions, trademark, tradename, etc. The cover member is configured to capture the exposed ends of tools 10-13 (FIG. 3) when it is placed over the work table and thereby prevent loss of the tools during transporting. It is also envisioned that the tools 10-13 may be connected to the work table by elongated connector means (not shown) such as a cord, strand, wire or the like to prevent tool loss.

While there have been described herein preferred embodiments of the invention, it is to be understood that various modifications and substitutions can be made in them within the scope of the amended claims which are intended to also include equivalents of such embodiments.