CN1849250A - Improved caulking gun - Google Patents

Abstract

A caulking gun for dispensing caulking material from a standard caulk tube. The gun is manufactured in three basic parts: a trigger assembly, a trigger housing, and a barrel housing for holding the tube. The facing portions of the barrel housing and trigger housing are provided with cooperating structure which enables the gun to be easily assembled and disassembled for storage in a toolbox in use. A novel drip/no drip feature is provided wherein a cam actuator conveniently located on the trigger housing enables the operator to select between no drip operation and drip type operation when caulking material and application requirements warrant such requirements. A thumb release mechanism is provided on the rear of the trigger housing so that the operator can release the drive rod to insert another caulk tube when the unit is placed in the drip position.

Description

Improved Caulking Gun

This application claims the benefit of U.S. Application Serial No. 10/874,628, filed June 23, 2004, which claims priority over U.S. Application Serial No. 60/491,353, filed July 31, 2003 right.

technical field

The present invention relates to a hand-held material dispensing device, such as a caulking gun, and more particularly to a particular type of construction of a caulking gun.

Background technique

Hand-held caulk guns are known in the art and typically rely on the action of a piston to push fluid out of a container towards the application area. The movement of the piston is guided by the advancement of the piston rod in the direction of the container, which is advanced in the direction of travel by the squeeze of the operator engaged thereon.

One such fluid dispenser is disclosed in US Patent No. 4,461,407 to Finnegan. Finnegan's patent incorporates an automatic pressure release mechanism such as is typical in many caulk guns of the prior art.

In US Patent No. 4,081,112 issued to Chang, a caulking gun is disclosed that has a forwardly biased spring to urge the trigger back to the cocked position after an activation cycle. US Patent No. 4,033,484 issued to Ornsteen discloses a hot melt adhesive gun which operates in a conventional manner of the prior art.

US Patent No. 3,069,053 issued to Nilsson and US Patent No. 3,189,226 issued to Sherbondy each show caulking guns with alternating piston rod trigger engagement arrangements. In these references, the trigger pushes the piston rod towards the fluid container by means of a ratchet mechanism.

The patents cited above are merely examples of the many caulk guns that are known in the art. As can be clearly seen in these examples, a standard caulk gun is configured to receive and hold a tube of caulk material. The caulk tube has a pointed nozzle at its front end to dispense caulk as the driven backplate presses it down from the other end. A long push rod in the body of the caulking gun is used to actuate the back plate of the caulking tube to extrude the caulking material. A trigger mechanism at the rear end of the caulking gun is used to advance the push rod when triggered by the user. A push plate is mounted on the front end of the push rod to distribute the force from the rod to the back plate at the end of the caulk pipe.

US Patent No. 5,887,765 issued to Broesamle discloses a caulking gun that relieves pressure on the backing plate when the operator is no longer engaging the trigger. Therefore, non-drip performance can be obtained with a mechanism that allows the push rod to slide back slightly so as to stop further ejection of caulk material. However, some types of caulk for proper application require constant pressure against the backplate even when the trigger is not being pushed, ie a ratchet type mechanism.

Model CG-00122 caulk gun manufactured by Great American Manufacturing, Inc. of Sun Valley, CA 91352 is characterized by a ratchet type caulk gun in which the user can select dripless or no-drip drip) operation. The selector switch changes angle whereby the spring biased plate engages one of a plurality of notches provided along the piston rod. This obtains the alternative method of operation. The barrel housing does not rotate, but is riveted to the handle housing.

The Model SI300, manufactured by Dripless, Inc. of Santa Rosa, CA 95403, is a non-drip, selective-drip caulk gun. In this model, a stop is provided on the rear of the handle housing. A compression spring biases this stop and is also exposed on the rear of the handle housing, so the mechanism could be easily damaged by being bumped or by the accumulation of dirt.

No caulking gun is found in the prior art that can function as a dropless unit as taught by Broesamle, or as a device of the dripping type as described above, that is driven only by driving the caulking gun. A lever switch on the gun's handle selects no-drip or standard operating method and features a rotating barrel that allows it to be easily disassembled so that the caulking gun can be conveniently packed in a tool box.

Contents of the invention

Particular devices according to the invention include caulking guns for dispensing caulking materials commonly used in construction work as well as in repairs and remodeling of dwellings and other types of construction. The caulking material is typically provided in a cylinder or tube with a hollow tip from which it is extruded by the action of a piston or back plate from the rear of the tube towards the tip. Due to the length and weight of the caulk tube, it is not uncommon to provide a support ("fender") extending towards the front of the handle below the caulk tube. The caulking gun is designed to hold in a receiving housing a caulking tube, usually a barrel in the form of a half cylinder, in which is mounted a longitudinally movable rod having a piston member at its front end to apply the caulking Material pushes out of the caulk tube.

The caulking gun further includes a hand-held grip handle secured to the handle housing, a trigger pivotably mounted to the housing for co-operation with the handle, and for connecting the trigger to the lever so that when the trigger is squeezed, The drive mechanism that drives the rod forward. There is also a mechanism for detaching the trigger from the linkage when the trigger is released. By repeated operation of the trigger, the rod and piston assembly can be advanced in the direction of the caulking tube tip, thereby providing means for dispensing the contents of the caulking tube through the forward facing nozzle.

There is also a precision knife for cutting the tip of the caulk tube which is actuated when the trigger is squeezed. Inserting the tip through the opening in the handle to the desired length and angle to access the knife, then squeezing the trigger causes the blade, which is inside the handle and attached to the trigger, to cut the tip cleanly and easily.

The caulk gun handle also includes a cam switch operated lever that enables the device to operate so that the lever does not disengage from the trigger when the trigger is released.

Typical prior art caulking guns are manufactured with the elongated barrel being an integral part of the gun; that is, the barrel and trigger housing or handle are manufactured together as a single unit. This makes it difficult for a rather bulky tool to be placed in the toolbox with other tools and tends to bend or deform due to contact with other tools in the toolbox.

The present invention features a caulking gun provided with a thumb-actuatable cam lever that engages and disengages a dog mechanism so that a no-drop state or a standard operating state can be selected. In addition, an extra long purge lever is provided at the top of the handle. The clamp is ergonomically shaped with an integral soft overmolded cushion to prevent operator fatigue. The invention also features a detachable barrel that can be easily removed from the handle at the end of the job and stowed into a tool box or into other transport equipment. The barrel can also be easily and quickly reloaded when required.

Briefly stated, the particular device of the present invention consists of two main parts which can be easily fastened together or separated. When assembled, the connection between the long barrel portion and the handle portion is firm and rigidly formed. However, the structural configuration of the connecting joint is such that the two elements can be easily and quickly separated from each other and easily and quickly connected together. Therefore, each of the two elements has a flat planar surface at the end facing the other element. The front end of the handle portion thus comprises a circular flat base. Projecting from the front surface of this base is a circular flat disc connected to said base by a portion of reduced diameter relative to the flat disc. The disc and the base are spatially separated by a portion of reduced diameter. This configuration forms an annular groove that defines an annular flange around the disc.

The rear end of the caulking gun barrel is shaped to mate with the front end of the handle portion. Accordingly, the front end of the barrel is shaped with an inwardly projecting flange extending approximately 180° in circumference around the central opening of the U-shaped structure. This U-shaped flange engages the outwardly projecting flange of the handle portion by means of a flat disc received in an interlocking formation until the two elements are fully engaged. A flange on the barrel slides over a flange on the handle portion and locks in place while the plunger is inserted. This allows for easy assembly and allows for partial rotation of the barrel relative to the handle without the need for additional hardware. The friction feel of the rotation of the handle part and the barrel is accomplished by utilizing different material hardness. For example, in a preferred embodiment, the flange and the flat connection part of the handle portion are made of fiber reinforced nylon. Whereas the flange and adjoining surfaces of the barrel portion are made of polypropylene or polyethylene. Assembly of the gun is accomplished by placing a push plate on the front end of the push rod and securing it in place with a nut threaded onto the end of the push rod. The caulking gun can then be operated in the usual manner and repeated squeezes forward with the trigger mechanism engaged on the push rod cause material to be extruded from the caulking gun. This configuration advantageously allows the barrel and caulk tube to be rotated relative to the handle portion in a desired manner for better placement of the nozzle when squeezing the caulk.

The handle portion itself is formed by a number of features which constitute improvements over prior art caulking guns. A thumb-operable lever is positioned on the top surface of the handle so that the drip/no-drip position can be easily selected. Located entirely in the top of the handle at the rear is a compression spring incorporating a silicon washer that allows drip-free operation. In the middle of the inside of the handle is a cam actuation which operates a thumb releasable stop switch for providing a drip/no drip condition. A leaf spring is used to push the stop against the cam actuator. By using this leaf spring, the mechanism can be packed into a very small compartment, which would be experienced if a compression type spring had been used. The top of the handle section is provided with a thin pivot rod that is used to penetrate the nozzle of the caulking tube. The rod is adapted to be moved into a position in line with the adjacent handle portion. A retaining member protruding from the handle portion is provided for stowing the rod. Thereafter an L-shaped protruding guard is provided which receives the rod when stowed and protects the user's hand from being stabbed by the rod.

The handle itself is at least partially coated with a cushioning layer to relieve stress on the user's hand from repeated squeezing of the handle's trigger. This cushioning layer can be any elastic material, such as foam or sponge rubber, foam polyurethane and the like. Near the top of this cushioning layer is a generally U-shaped molded protrusion that extends around the rear of the handle. This helps the handle to rest in the user's hand by arresting the hand as it moves up the handle to the working position.

The trigger member is formed with three finger receiving portions extending downwardly from the upper end of the trigger. The first two are shaped to fit the first and second fingers of a typical user; the third, near the tip of the trigger, is shaped to accommodate the two fingers that would be the third and fourth fingers on the user's hand . This provides a fuller and more comfortable handle that better accommodates the user's hand.

Description of drawings

The present invention can be better understood from the following more detailed description taken in conjunction with the accompanying drawings, in which:

Figure 1 is a schematic perspective view taken from the left rear quarter of a particular arrangement of a caulking gun according to the present invention;

Figure 2 is an exploded view of the caulking gun of Figure 1 showing only the removable barrel features;

Fig. 3 is a schematic top view of the caulking gun in Fig. 1;

4A is a side cross-sectional view of the caulking gun of FIG. 1 taken along line 4-4 of FIG. 3;

Figure 4B is an enlarged view of the identified portion in Figure 4A;

Figure 5 is a perspective view of the handle portion of the caulking gun of Figure 1, showing the rod 40 in the use position;

Figure 6 is a side elevational view of the handle portion of Figure 5 taken from its right hand side;

7 is a perspective view of the barrel portion of the caulking gun of FIG. 1 with the handle portion removed; and

Figure 8 is a schematic front view of the barrel portion of Figure 7 taken from its left hand side.

Figure 9 is a perspective view of a drip switch stopper.

Fig. 10 is a perspective view of a leaf spring.

Figure 11 is a perspective view of the cam lever assembly.

Figure 12 is a top view of the precision tool.

Detailed ways

As shown in the drawings, and with particular reference to FIG. 1 , the illustrated preferred embodiment 10 includes a cylindrical tube housing 12 and a handle portion or trigger housing 14 . The cylindrical pipe housing 12 is cut away along the side wall 22 to allow easy insertion of the caulking tube into the pipe housing. This element 22 is a stiffening rib mounted longitudinally along the outside of the tube shell 12 to increase rigidity and to support the tube shell, in particular to support the edge portion of the semi-cylindrical. Another pair of stiffening ribs below the designated element 22 provides reinforcement to the tube shell at the lower center cut-off position shown in FIG. 7 .

Also shown in FIG. 7 (and in FIG. 2 ) is a pair of triangular members 27 located at the front end of the tube housing 12 to provide reinforcement to the front wall 25 attached thereto.

Passing through both housings is a piston rod 16 . Although the piston rod 16 is shown fitted in the trigger housing 14, it can be withdrawn from the rear end of the housing 14 for complete removal. With the piston rod removed, the two parts can be easily disassembled. When the caulking gun is fully assembled, the piston rod 16 passes through central holes 20A and 20B in the cylindrical tube portion and the handle portion, respectively. Still shown in FIG. 2 is a push plate 24 and a lock nut 26 for mounting on the threaded front end 28 of the piston rod 16 .

Positioned in the middle portion 66 of the seamless box design trigger housing 14 is a drip/no drip selection mechanism 60, which is described in detail below. A lever arm 90 (shown in FIG. 11 ) enables movement of the mechanism 60 to either the drip position 62 or the non-drip position 64 as indicated by markings provided on the trigger housing 14 . A thumb release portion 68 extending downwardly from the trigger housing 14 enables the operator to easily release the lever 16 so that it can be removed from the rear.

2, 5 and 6 are views of the handle portion 14 with the no-drip/no-drip mechanism 60 removed for clarity. These figures both show a circular flat bottom surface 30 and a connecting flange 32 displaced by an annular groove 34 . Also shown is a trigger 36 pivotably mounted in the handle housing 14 , which together with a downwardly extending portion 38 forms the handle of the housing 14 . The thin rod 40 is shown extending perpendicularly from the mounting member 42 . The rod 40 is provided to penetrate the nozzle of the caulking pipe or to clean the opening in the caulking pipe once the nozzle has been penetrated. The rod 40 is stowed by rotation about a pivot member 42 to a retaining member 41 extending along the side of the housing 14 .

Near the rear end of the housing 14 is an L-shaped protrusion 43 into which the end of the rod 40 fits when the rod 40 is stowed into the retaining member 41 . The protrusion 43 is a guard for protecting the user's hand from being stabbed by the end of the rod 40 when using the caulking gun.

Also shown in FIGS. 5 and 6 is the cushioning layer 37 along the back of the downwardly extending portion 38 . This layer 37 is adhered to the part 38, for example by melting during the molding process, and the part 38 has a U-shaped stop part 39 protruding outwards. Layer 37 and protrusion 39 are molded together and extend around the back of portion 38 and along both sides of portion 38 . The raised U-shaped member 39 helps position the caulking gun in the user's hand as the grip portion of the hand rests directly on the U-shaped protrusion 39 .

Along the length of trigger 36 is a series of finger indentations 35A and 35B. These finger indentations are shaped to fit the user's fingers; the upper two indentations 35A are shaped to receive the first and second fingers of the user's hand. The lowermost indentation 35B is longer to accommodate the third and fourth fingers of the user's hand. This configuration provides for a very comfortable, natural grip on the tool, by virtue of its shape enabling the user to keep the handle part in the hand without the possibility of the handle slipping from its natural position.

Figures 7 and 8 are views of the barrel. A U-shaped opening 23 in the front wall 25 of the barrel 12 is provided to allow the nozzle of the caulking tube to extend forwardly from the barrel. The rear end of the barrel 12 is formed with a planar surface 50 having an inner cavity 52 with a radially inwardly projecting edge 54 formed as an inverted U defining an inner flange. Shaped, the inner flange is adapted to engage with the outwardly extending flange 32 of the handle portion 14 . Edge 54 forms a circular groove that does not extend completely around central opening 20A.

FIG. 8 is an enlarged view of the barrel portion 12 depicted in FIG. 4 . Displacing the edge 54 of the cavity 52 from the inner end of the lumen 52 by separating the edge 54 from the front surface 56 by the semi-annular groove forms an inwardly directed flange to engage the flange 32 .

The barrel 12 is shaped to form a central groove 21 to hold the caulk tube. The barrel 12 is open over the groove 21 to allow rapid insertion of the caulking tube. When in place, the caulking tube extends into a groove 55 at the rear of the barrel 12 .

The barrel 12 of the present invention is a significant improvement over the prior art due to the construction of the two mating parts of the gun, which can be quickly assembled and disassembled when installed for use or stored in a tool box. The connecting parts between the two parts of the caulking gun have a specific configuration that creates the connection of strength and stiffness required to support the caulking pipe in use.

The barrel 12 can be configured to fit the size of a standard caulk tube or simply by adjusting the size of the barrel housing 12 to a larger quart size.

Referring now to Figures 4A, 4B, 9, 10, 11, the anti-drip/non-drip mechanism 60 of the present invention 10 is shown. The dropless mechanism functions similarly to that disclosed in US Patent No. 5,887,765, which is incorporated herein by reference. When the trigger 36 is pushed, the drive stop 74 biased by the compression spring 76 advances the rod 16, thus causing the caulk (not shown) to be squeezed. Silicon washer clamp 72 provides forward biasing of rod 16 . This mechanism biases the rod 16 in a forward direction by the clamping force of the clamping member 72 and the elastic force of the spring 78, preventing the rod 16 from moving rearwardly beyond what is required to relieve the tension in the caulking tube when the trigger 36 is released. pressure. The frictional clamping can be overcome by pushing the rod 16 back so that a new tube of caulk can be inserted.

The non-drip mechanism has three main elements: a cam lever actuator 61 , a drip switch dog 70 and a leaf spring 80 . When the cam lever actuator 61 is turned towards the non-dripping position 64, the invention 10 operates as explained above. However, when the cam lever actuator 61 is moved towards the drip position 62, a "dripping feature" is provided. The leaf spring 80 is urged against the drip switch stop 70 . The rod 16 passes through the opening 92, which has sharp edges. Preferably, the stopper 70 has a glossy galvanized coating. When in the non-dripping position, the cam 74 makes the stop 70 substantially perpendicular to the rod 16 , allowing the rod 16 to pass through the hole 92 unimpeded. When in the drip position, cam 74 engages the edge of opening 92 with rod 16 as shown in FIG. . To release the cam 74 , the operator simply pushes the thumb release 68 of the stop 70 . The stop 70 is fitted into the slot 71 by means of a rivet passing through an opening 84 in the stop 70 and an opening 82 in the leaf spring 80 and is biased by the leaf spring. As shown, the entire drip/no-drip mechanism 60 is housed in the middle portion 66 . Using leaf spring 80 instead of compression springs such as springs 78 and 76 reduces the amount of space needed to house this mechanism.

As shown in Figure 12, a precision knife 102 is provided to cut through the tip 100 of a caulk tube (not shown). The knife 102 is connected to the trigger assembly 36 so pushing the trigger causes the knife 102 to slide forward thereby severing the tip 100 which has been inserted into the opening 99 of the trigger housing 14 .

While certain exemplary embodiments of this invention have been described herein for illustrative purposes, it will be obvious to those skilled in the art that modifications may be made therein without departing from the spirit and scope of the invention.

Claims (17)

CLAIMS 1. A caulking gun for dispensing a caulking material enclosed in a tube having a nozzle, said caulking gun comprising: A rotatable barrel housing that holds the caulking tube; a trigger housing releasably connected to the barrel housing; a trigger assembly pivotally connected to the trigger housing; a piston rod positioned longitudinally extending in the barrel housing and slidably connected to the trigger housing; a push plate releasably connected to the piston rod for pressing the caulk out of the caulk by moving the push plate in the caulk tube when the trigger assembly is squeezed tube, and when the push plate is removed from the piston rod, the barrel housing can be disengaged from the trigger housing, whereby the caulking gun can be compared to the barrel housing It is easier to stow when attached to the trigger housing. 2. The caulking gun of claim 1, wherein said caulking gun further comprises attachment means for releasably attaching said barrel housing to said trigger housing. 3. The caulking gun of claim 1, wherein said trigger housing further includes a precision knife assembly coupled to said trigger assembly for cutting away said caulk when said trigger assembly is squeezed the tip of the tube. 4. The caulking gun of claim 1, wherein the trigger housing further includes a pivotable lever connected to the trigger housing, the lever operable to pierce the nozzle of a caulking tube, and The rod is stowed in the L-shaped raised guard when not in use to prevent injury. 5. The caulking gun of claim 1, wherein the trigger housing further includes a handle at least partially covered with a cushioning layer to relieve strain on an operator's hand when repeatedly squeezing the trigger assembly. pressure. 6. The caulking gun of claim 1, wherein said trigger assembly has an upper end, and further includes a finger receiving portion, said finger receiving portion having three indentations extending downwardly from the upper end, wherein The first indent is used to support the index finger of the operator's hand, the second indent is used to support the middle finger of the operator, and the bottommost indent is used to support the ring finger and little finger of the operator's hand. 7. A caulking gun for dispensing caulking material enclosed in a tube having a nozzle, the caulking gun comprising: The barrel housing, which is used to hold the caulking tube; a trigger housing connected to the barrel housing; a trigger assembly pivotally connected to the housing; an uncut piston rod positioned longitudinally in the barrel housing and slidably connected to the trigger housing; a push plate connected to the piston rod; drive means connected to the trigger assembly for forcing the caulk material out of the caulk tube by moving the push plate within the caulk tube when the trigger assembly is squeezed; forward biasing means to prevent the piston rod from moving rearwardly more than is necessary to reduce the pressure in the caulk tube when the trigger assembly is released, thereby providing "no drip" operation; a stop means for preventing the piston rod from moving backwards when the trigger assembly is released, thereby providing a "dripping" operation; wherein the stop means is located along the piston rod between the drive means and the between the forward biasing devices described above. Actuating means for selecting between "no drip" operation and "dripping" operation, wherein said actuating means disengages the stop means. 8. The caulking gun of claim 7, wherein said trigger housing further includes a precision knife assembly coupled to said trigger assembly for cutting said caulk when said trigger assembly is squeezed the tip of the tube. 9. The caulking gun of claim 7, wherein the trigger housing further includes a pivotable lever connected to the trigger housing, the lever operable to pierce the nozzle of the caulking tube, and The rod is stowed in the L-shaped raised guard when not in use to prevent injury. 10. The caulking gun of claim 7, wherein the trigger housing further includes a handle at least partially covered with a cushioning layer to relieve strain on an operator's hand when repeatedly squeezing the trigger assembly. pressure. 11. The caulking gun of claim 7, wherein the trigger assembly has an upper end, and further includes a finger receiving portion, the finger receiving portion having three indentations extending downwardly from the upper end, wherein the first One indent supports the index finger of the operator's hand, the second indent supports the middle finger of the operator's hand, and the bottommost indent supports the ring and little fingers of the operator's hand. 12. A caulk gun for dispensing caulk material enclosed in a tube having a nozzle, the caulk gun comprising: a rotatable barrel housing for holding the caulking tube; a trigger housing releasably connected to the barrel housing; a trigger assembly pivotally connected to the trigger housing; a piston rod positioned longitudinally extending in the barrel housing and connected to the trigger housing; a push plate releasably connected to the piston rod so that when the push plate is removed from the piston rod, the barrel housing can be disengaged from the trigger housing, thereby the caulking gun can be stowed more easily than when the barrel housing is attached to the trigger housing; drive means connected to the trigger assembly for forcing the caulk material out of the caulk tube by moving the push plate within the caulk tube when the trigger assembly is squeezed; A forward biasing device which serves to prevent the piston rod from moving rearwardly more than necessary to reduce the pressure in the caulk tube when the trigger assembly is released, thus providing "no drip" operation ; stop means for preventing rearward movement of the piston rod when said trigger assembly is released, thereby providing a "drip" operation; Actuating means for selecting between "no drip" operation and "dripping" operation, wherein said actuating means disengages the stop means. 13. The caulking gun of claim 12, wherein said caulking gun further comprises attachment means for releasably attaching said barrel housing to said trigger housing. 14. The caulking gun of claim 12, wherein said trigger housing further includes a precision knife arrangement coupled to said trigger assembly for cutting said caulk when said trigger assembly is squeezed the tip of the tube. 15. The caulking gun of claim 12, wherein the trigger housing further includes a pivotable lever connected to the trigger housing, the lever operable to pierce the nozzle of the caulking tube, and The rod is stowed in the L-shaped raised guard when not in use to prevent injury. 16. The caulking gun of claim 12, wherein the trigger housing further includes a handle at least partially covered with a cushioning layer to relieve strain on an operator's hand when repeatedly squeezing the trigger assembly. pressure. 17. The caulking gun of claim 12, wherein the trigger assembly has an upper end, and further includes a finger receiving portion, the finger receiving portion having three indentations extending downwardly from the upper end, wherein the first One indent supports the index finger of the operator's hand, the second indent supports the middle finger of the operator's hand, and the bottommost indent supports the ring and little fingers of the operator's hand.

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