EP3950145A1

EP3950145A1 - Dual cartridge caulking gun

Info

Publication number: EP3950145A1
Application number: EP21151990.5A
Authority: EP
Inventors: Wei-Cheng Huang
Original assignee: Kai Shyun Enterprise Co Ltd
Current assignee: Kai Shyun Enterprise Co Ltd
Priority date: 2020-08-04
Filing date: 2021-01-18
Publication date: 2022-02-09
Anticipated expiration: 2041-01-18
Also published as: TWI762987B; EP3950145B1; TW202206192A

Abstract

A dual cartridge caulking gun (100) includes a gun body (10), a receptacle (20) for receiving a caulking gun caddy (1), a plunger unit (30) having first and second plungers (31, 32) longitudinally movable to expel material filled in first and second tubular barrels (101, 102) of the caddy (1), a trigger unit (40), and an adjusting unit (50) pivotably mounted on the receptacle (20) to be movable along an arcuate surface (27) on the receptacle (20) between two supporting positions where first and second wall surface segments (524, 525) support the second tubular barrels (102) with different diameters.

Description

The disclosure relates to a caulking gun, and more particularly to a dual cartridge caulking gun.
A conventional dual cartridge caulking gun is employed to receive two caulking, gluing or sealing materials that are mixed for use with a predetermined and varying mixing ratio. A dual cartridge caulking gun as disclosed in TW M439526 includes a gun body and a receptacle mounted on a front side of the gun body for supporting a caulking gun caddy with two tubular barrels. A clamp structure is provided and includes a U-shaped clamp body detachably anchoring the receptacle, and two adjusting clips sleeved on two dovetail portions of the clamp body and each having a stack of clip plates. With the selected clip plates attached to the dovetail portions, the clips are adjustable to support the tubular barrels with different sizes or shapes or volumes.
However, the clips must be removed from the clamp body during adjustment, which renders the operation inconvenient. The removed clips might be easily misplaced.
Another dual cartridge caulking gun as disclosed in TW I577456 includes a U-shaped clip body, two front arc sheets and two rear arc sheets . The clip body has a vertical plate and upper and lower side plates. The inner sides of the upper and lower side plates have inner and outer arc surfaces having different curvatures, respectively. The front and rear arc sheets extend from the outer arc surfaces of the upper and lower side plates. With arrangement of the front and rear arc sheets and their elasticity, and the curvatures of the arc surfaces, the caulking gun can hold the tubular barrels with different diameters. However, such clip structure is complicated in structure and arduous to manufacture and fabricate. Moreover, the clip structure is loosely disposed to the receptacle of the caulking gun for facilitating adjustment. As such, the clip might be easily undesirably removed and misplaced.
Therefore, an object of the disclosure is to provide a dual cartridge caulking gun that can alleviate at least one of the drawbacks of the prior art.
According to the disclosure, the dual cartridge caulking gun is adapted to mount a caulking gun caddy for expelling and dispensing material filled in the caddy. The caddy has a first tubular barrel and a second tubular barrel juxtaposed and coupled with the first tubular barrel in a longitudinal direction. The dual cartridge caulking gun includes a gun body, a receptacle mounted on a side of the gun body, a plunger unit mounted within and movable relative to the receptacle in the longitudinal direction, a trigger unit mounted on the gun body, and an adjusting unit. The receptacle has an accommodation space for receiving and supporting the caddy, and at least one arcuate surface which faces the accommodation space. The plunger unit includes a first plunger which is actuated by a triggering action, and a second plunger which is movable with the first plunger. The second plunger is elongated along a central line parallel to the longitudinal direction. The trigger unit is operable to drive movement of the plunger unit in the longitudinal direction toward the accommodation space. The adjusting unit is pivotably mounted on the receptacle to be movable along the arcuate surface, and has an arcuate first wall surface segment and an arcuate second wall surface segment which are angularly spaced apart from each other and which face the central line. The adjusting unit is turnable relative to the receptacle between a first supporting position, where a curvature center of the first wall surface segment meets the central line, and a second supporting position, where a curvature center of the second wall surface segment meets the central line. A distance between the first wall surface segment and the central line in the first supporting position is larger than a distance between the second wall surface segment and the central line in the second supporting position. The first and second wall surface segments support the second tubular barrels with different diameters.
Other features and advantages of the disclosure will become apparent in the following detailed description of the embodiments with reference to the accompanying drawings, of which:

FIG. 1 is a perspective view illustrating a first embodiment of a dual cartridge caulking gun according to the disclosure;
FIG. 2 is a fragmentary, enlarged perspective view of the first embodiment;
FIG. 3 is an exploded perspective view of the first embodiment;
FIG. 4 is an exploded perspective view of an adjusting unit of the first embodiment;
FIG. 5 is a sectional view of the first embodiment;
FIG. 6 is a sectional view taken along line VI-VI of FIG. 5;
FIG. 7 is a sectional view taken along line VII-VII of FIG. 5;
FIG. 8 is a sectional view taken along line VIII-VIII of FIG. 5;
FIG. 9 is a fragmentary schematic view illustrating the state when the adjusting unit is adjusted;
FIG. 10 is a sectional view taken along line X-X of FIG. 9;
FIG. 11 is a fragmentary sectional view illustrating a second embodiment of a dual cartridge caulking gun;
FIG. 12 is a fragmentary, exploded perspective view illustrating a third embodiment of a dual cartridge caulking gun; and
FIG. 13 is a fragmentary sectional view of the third embodiment.

Before the disclosure is described in greater detail, it should be noted that where considered appropriate, reference numerals or terminal portions of reference numerals have been repeated among the figures to indicate corresponding or analogous elements, which may optionally have similar characteristics.
Referring to FIGS. 1 to 3, a first embodiment of a dual cartridge caulking gun 100 is adapted to mount a caulking gun caddy 1 for expelling and dispensing material filled in the caddy 1. The caddy 1 has a first tubular barrel 101, a second tubular barrel 102 juxtaposed and coupled with the first tubular barrel 101 in a longitudinal direction (X), and a nozzle 103 connected with one end of each of the first and second tubular barrels 101, 102. The dual cartridge caulking gun 100 includes a gun body 10, a receptacle 20, a plunger unit 30, a trigger unit 40 and an adjusting unit 50.
The gun body 10 includes a mount 11 and a handle 12 connected to the mount 11. The mount 11 defines a receiving chamber 111 and an axial hole 112 communicating with the receiving chamber 111.
The receptacle 20 includes a first end wall 21 connected to a side of the mount 11, a second end wall 22 disposed opposite to the first end wall 21 in the longitudinal direction (X), a first lateral wall 23 connected between the first and second end walls 21, 22 and having an arcuate surface 27 to support the first tubular barrel 101 (see FIG. 6), a second lateral wall 24 connected between the first and second end walls 21, 22, disposed opposite to the first lateral wall 23 in a transverse direction (Y) that is transverse to the longitudinal direction (X) and having another arcuate surface 27, an arcuate slot 25 formed in the second lateral wall 24, and a retaining plate 28 disposed to the first end wall 21 to fasten the receptacle 20 to a side of the gun body 10. The first end wall 21, the second end wall 22, the first lateral wall 23 and the second lateral wall 24 cooperatively define an accommodation space 26 for receiving and supporting the caddy 1 such that the arcuate surfaces 27 of the first and second lateral walls 23, 24 face the accommodation space 26. The first end wall 21 has a first hole 211, an elongated round second hole 212 formed at one side of the first hole 211, and an auxiliary hole 213 formed at the other side of the first hole 211. The second end wall 22 has a slot 221 for the nozzle 103 to extend therethrough (see FIG. 5). With reference to FIGS. 2 and 6, the arcuate slot 25 is formed adjacent to the first end wall 21, and has a lower end 251, an upper end 252 opposite to the lower end 251, and two round holes 253 interposed between the upper and lower ends 252, 251.
The plunger unit 30 is mounted on the mount 11 and within the receptacle 20 and is movable relative to the receptacle 20 in the longitudinal direction (X). The plunger unit 30 includes a first plunger 31 which extends through the first hole 211 and which is actuated by a triggering action, a second plunger 32 which extends through the second hole 212 and which is movable with the first plunger 31, an auxiliary plunger 33 which extends through the auxiliary hole 213, a crosspiece 34 which is connected with one end of each of the first, second and auxiliary plungers 31, 32, 33, and a pull knob 35 which is fastened to the crosspiece 34 and the first plunger 31. A first plunger disc 36 is connected with the other end of each of the first and auxiliary plungers 31, 33. A second plunger disc 37 is connected with the other end of the second plunger 32. The first plunger 31 is elongated in the longitudinal direction (X) to be disposed in the receiving chamber 111 and the axial hole 112. In this embodiment, the second plunger 32 has a plunger rod 321 elongated along a central line (L) parallel to the longitudinal direction (X), and an enlarged end head 322 which extends transversely from and is integrally formed with an end of the plunger rod 321 such that the second plunger 32 has an L-shaped cross-section along the central line (L). The second plunger 32 is adjustable relative to the first plunger 31 in the transverse direction (Y). With reference to FIGS. 7 and 8, the plunger rod 321 has a width which is measured in an upright direction (Z) that is transverse to both the longitudinal direction (X) and the transverse direction (Y) and which is smaller than a width of the end head 322 which is measured in the upright direction (Z). The crosspiece 34 has a rectangular inner sliding hole 341 which is aligned with the central line (L), and an elongated round outer sliding hole 342 which is in spatial communication with the inner sliding hole 341 along the central line (L) and which is elongated in the transverse direction (Y). The outer sliding hole 342 has a width which is measured in the upright direction (Z) and which is smaller than a width of the inner sliding hole 341 that is measured in the upright direction (Z). The plunger rod 321 extends through the outer sliding hole 342 and the second hole 212. The end head 322 is slidably disposed in the inner sliding hole 341, and the plunger rod 321 is slidable in the outer sliding hole 342 in the transverse direction (Y).
The trigger unit 40 includes a trigger lever 41 pivotably connected to the mount 11, an actuated block 42 sleeved on the first plunger 31 and disposed in the receiving chamber 111, a first biasing spring 43 disposed between the actuated block 42 and the receptacle 20, a returning presser 44 sleeved on the first plunger 31 and disposed between the gun body 10 and the crosspiece 34, and a second biasing spring 45 disposed between the gun body 10 and the returning presser 44. The trigger lever 41 is pullable to actuate the actuated block 42 to move the first and auxiliary plungers 31, 33 forwards toward inside of the first tubular barrel 101 and to move the second plunger 32 forwards in the longitudinal direction (X) toward inside of the second tubular barrel 102. The returning presser 44 is pressed to actuate returning movement of the first, auxiliary and second plungers 31, 33, 32 in an opposite direction.
Referring to FIG. 4, the adjusting unit 50 is pivotably mounted on the receptacle 20 to be movable along the arcuate surface 27 of the second lateral wall 24. The adjusting unit 50 includes an adjusting piece 501 which is pivotably mounted on the retaining plate 28, a knob piece 502 which is rotatably connected to the adjusting piece 501, and a screw 503 which extends through the adjusting piece 501 and threadedly engages with the knob piece 502. The adjusting piece 501 has a flat plate portion 51 which is disposed adjoining and parallel with an inboard side of the first end wall 21 and is disposed within the accommodation space 26, and an arcuate plate portion 52 which extends from the flat plate portion 51 in the longitudinal direction (X) and which is movable on and relative to the arcuate surface 27 of the second lateral wall 24. The flat plate portion 51 has a pivot pin 511 which is journalled on either one of the retaining plate 28 and the first end wall 21, and a penetrating slot 512 which is registered with the second hole 212 for the second plunger 32 to extend therethrough. The penetrating slot 512 is elongated and round in shape, and has a round first end portion 514 and a round second end portion 515 opposite to each other. The arcuate plate portion 52 has a bearing wall 521 which has arcuate first and second wall surface segments 524, 525 for supporting the second tubular barrel 102 thereon, and an outer surface 522 radially opposite to the first and second wall surface segments 524, 525, two sliding feet 523 which extend radially and outwardly from the outer surface 522 of the bearing wall 521 and which slidably abut against the arcuate surface 27 of the second lateral wall 24, and a mount projection 526 which projects radially and outwardly from the outer surface 522 of the bearing wall 521 and between the two sliding feet 523. The first and second wall surface segments 524, 525 are angularly spaced apart from each other and face the central line (L). With reference to FIGS. 6 and 10, the adjusting unit 50 is turnable with the pivot pin 511 relative to the receptacle 20 between a first supporting position (see FIG. 6), where a curvature center of the first wall surface segment 524 meets the central line (L), and a second supporting position (see FIG. 10), where a curvature center of the second second wall surface segment 525 meets the central line (L). In this embodiment, a distance (d1) between the first wall surface segment 524 and the central line (L) in the first supporting position is larger than a distance (d2) between the second wall surface segment 525 and the central line (L) in the second supporting position. Therefore, the first wall surface segment 524 (FIG. 6) serves to support the second tubular barrel 102 when the second tubular barrel 102 has a larger diameter, and the second wall surface segment 525 serves to support the second tubular barrel 102 when the second tubular barrel 102 has a smaller diameter (FIG. 10). Additionally, the curvature center of the first wall surface segment 524 is located at a circle center of the first end portion 514 of the penetrating slot 512, and the curvature center of the second wall surface segment 525 is located at a circle center of the second end portion 515 of the penetrating slot 512. In this embodiment, a curvature of the second wall surface segment 525 is larger than a curvature of the first wall surface segment 524.
Referring again to FIGS. 3, 4 and 6, each of the sliding feet 523 projects from the outer wall surface 522 and is in the form of a curve wedge rib having a curve edge 5231 that extends around the pivot pin 511. The knob piece 502 has a rotating portion 53 which is slidably inserted into the arcuate slot 25 and is journalled on the mount projection 526 to permit rotation of the knob piece 502 relative to the adjusting piece 501, and an operating portion 54 which is connected with the rotating portion 53 to project from the accommodation space 26 through the arcuate slot 25. Referring to FIGS. 4 and 9, the rotating portion 53 has two flat surface segments 531 diametrically opposite to each other, and two curve surface segments 532 each interposed between the two flat surface segments 531 and diametrically opposite to each other. A length between the curve surface segments 532 is larger than that between the flat surface segments 531, and is not larger than a diameter of the round holes 253.
With reference to FIGS. 5 to 8, when a caulking gun caddy 1 has been placed within the accommodation space 26, the first tubular barrel 101 is supported by the arcuate surface 27 of the first lateral wall 23, and the second tubular barrel 102 is supported by the bearing wall 521 of the adjusting unit 50. As shown in FIGS. 5 and 6, when the adjusting unit 50 is in the supporting position, the first wall surface segment 524 supports the second tubular barrel 102 with a larger diameter, the second plunger 32 extends through the penetrating slot 512 and is aligned with the center of the first end portion 514, and the knob piece 502 is retained to the round hole 253 of the arcuate slot 25 adjacent to the lower end 251. As shown in FIG. 9, in this retained position, the curve surface segments 532 of the rotating portion 53 are parallel to the arcuate slot 25 to be retained in the round hole 253. The first and auxiliary plungers 31, 33 and the first plunger disc 36 are actuated to push the first tubular barrel 101, and the second plunger 32 and the second plunger disc 37 are actuated to push the second tubular barrel 102. By pulling the trigger lever 41 to actuate the actuated block 42, the plunger unit 30 is moved forwards along the longitudinal direction (X) toward the accommodation space 26 so as to expel materials filled in the first and second tubular barrels 101, 102 and to dispense the materials from the nozzle 103.
During adjusting operation, the caulking gun caddy 1 having the second tubular barrel 102 with a larger diameter is first taken out from the accommodation space 26. Subsequently, the operating portion 54 is turned to a slidable position, where the flat surface segments 531 are parallel to the arcuate slot 25 and the curve surface segments 532 are removed from the round hole 253. The rotating portion 53 of the knob piece 502 is permitted with a sliding movement along the arcuate slot 25 so as to turn the adjusting unit 50 about an axis of the pivot pin 511. The penetrating slot 512 is moved upwardly such that the second plunger 32 is moved with the penetrating slot 512 toward the first plunger 31, the end head 322 is slided in the inner sliding hole 341 (see FIG. 8), and the plunger rod 321 is slided in the outer sliding hole 342 and the second hole 212. At this stage, the second plunger 32 is aligned with the center of the second end portion 515 of the penetrating slot 512 (see FIG. 10). Subsequently, the operating portion 54 is turned back to the retained position to prevent movement of the adjusting unit 50 relative to the receptacle 20. A caulking gun caddy 1 having a second tubular barrel 102 with a smaller diameter is placed in the accommodation space 26. The second wall surface segment 525 supports the second tubular barrel 102 with a smaller diameter. As such, by the adjusting operation, the caulking gun can mount caulking gun caddies with different sizes and mixing ratios. That is, as shown in FIGS. 6 and 10, the second plunger 32 can be actuated to push the second tubular barrel 102 when the second tubular barrel 102 is supported by the first wall surface segment 524 and has a larger diameter and the second plunger 32 is at the first end portion 514 of the penetrating slot 512, and to push the second tubular barrel 102 when the second tubular barrel 102 is supported by the second wall surface segment 525 and has a smaller diameter and the second plunger 32 is at the second end portion 515 of the penetrating slot 512.
When it is needed to replace the caulking gun caddy 1 having an original size with that having a different size, the adjusting unit 50 can be turned to the desired supporting position without the need to remove any component part from the gun 100. The adjusting operation is convenient and easy to conduct, and misplacement of component parts is prevented.
Referring to FIG. 11, in a second embodiment, the end head 322' of the second plunger 32 of the plunger unit 30 is in the form of a flat head screw which is detachably fastened to the end of the plunger rod 321.
Referring to FIGS. 12 and 13, in a third embodiment, the operating portion 54 of the knob piece 502 of the adjusting unit 50 further has an inner end surface 541 formed adjacent to the rotating portion 53 and facing the mount projection 526, and two pairs of retaining recesses 542, 543 formed in the inner end surface 541. The retaining recesses 542, 543 of each pair are diametrically opposite to each other, and all the retaining recesses 542, 543 are angularly spaced apart from one another. The mount projection 526 has two pegs 527 which project to engage in selected ones of the retaining recesses 542, 543 to retain the knob piece 502 to the adjusting piece 501. The adjusting unit 50 further includes a biasing spring 504 which is disposed between the screw 503 and the adjusting piece 501 so as to bias the retaining recesses 542, 543 toward the pegs 527.
When the operating portion 54 is in the retained position, where the curve surface segments 532 of the rotating portion 53 are parallel to the arcuate slot 25 to be retained in the round hole 253, the pegs 527 are engaged in the retaining recesses 542 so as to prevent turning of the knob piece 502 relative to the receptacle 20. During the adjusting operation of the adjusting unit 50, the operating portion 54 is first pulled (the biasing spring 504 is compressed) to remove the retaining recesses 542 from the pegs 527, and is then turned to the slidable position, where the flat surface segments 531 are parallel to the arcuate slot 25 and the curve surface segments 532 are removed from the round hole 253 so as to permit sliding movement of the adjusting piece 501 along the arcuate slot 25 to the desired supporting position. Finally, the operating portion 54 is released to permit engagement of the retaining recesses 543 with the pegs 527 by means of biasing action of the biasing spring 504.

Claims

A dual cartridge caulking gun (100) adapted to mount a caulking gun caddy (1) for expelling and dispensing material filled in the caddy (1), the caddy (1) having a first tubular barrel (101) and a second tubular barrel (102) juxtaposed and coupled with the first tubular barrel (101) in a longitudinal direction (X), said dual cartridge caulking gun (100) comprising:
a gun body (10);

a receptacle (20) mounted on a side of said gun body (10), and having an accommodation space (26) for receiving and supporting the caddy (1), and at least one arcuate surface (27) which faces said accommodation space (26);

a plunger unit (30) mounted within and movable relative to said receptacle (20) in the longitudinal direction (X), said plunger unit (30) including a first plunger (31) which is actuated by a triggering action, and a second plunger (32) which is movable with said first plunger (31), said second plunger (32) being elongated along a central line (L) parallel to the longitudinal direction (X); and

a trigger unit (40) mounted on said gun body (10) and operable to drive movement of said plunger unit (30) in the longitudinal direction (X) toward said accommodation space (26), characterized by:
an adjusting unit (50) pivotably mounted on said receptacle (20) to be movable along said arcuate surface (27), and having an arcuate first wall surface segment (524) and an arcuate second wall surface segment (525) which are angularly spaced apart from each other and which face the central line (L), said adjusting unit (50) being turnable relative to said receptacle (20) between a first supporting position, where a curvature center of said first wall surface segment (524) meets the central line (L), and a second supporting position, where a curvature center of said second wall surface segment (525) meets the central line (L), a distance (d1) between said first wall surface segment (524) and the central line (L) in the first supporting position being larger than a distance (d2) between said second wall surface segment (525) and the central line (L) in the second supporting position.
The dual cartridge caulking gun (100) as claimed in Claim 1, characterized in that said receptacle (20) includes a first end wall (21) connected to said gun body (10), a second end wall (22) disposed opposite to said first end wall (21) in the longitudinal direction (X), a first lateral wall (23) connected between said first and second end walls (21, 22) and having one of said at least one arcuate surface (27) to support the first tubular barrel (101), a second lateral wall (24) connected between said first and second end walls (21, 22) and disposed opposite to said first lateral wall (23) in a transverse direction (Y) that is transverse to the longitudinal direction (X), and an arcuate slot (25) formed in either one of said first end wall (21) and said second lateral wall (24), said second lateral wall (24) having the other one of said at least one arcuate surface (27), said first end wall (21) having a first hole (211) for said first plunger (31) to extend therethrough, and an elongated round second hole (212) for said second plunger (32) to extend therethrough and permitting movement of said second plunger (32) in the transverse direction (Y) relative to said first plunger (31),
said adjusting unit (50) including a flat plate portion (51) which is mounted at a side of said first end wall (21) and in said accommodation space (26), an arcuate plate portion (52) which extends from said flat plate portion (51) in the longitudinal direction (X) and which is movable on and relative to said arcuate surface (27) of said second lateral wall (24), and an operating portion (54) which is connected with either one of said flat plate portion (51) and said arcuate plate portion (52) and disposed outwardly of said accommodation space (26), said flat plate portion (51) having a pivot pin (511) which is journalled on said first end wall (21), and a penetrating slot (512) which is registered with said second hole (212) for said second plunger (32) to extend therethrough, said arcuate plate portion (52) having a bearing wall (521) which has said first and second wall surface segments (524, 525) for supporting the second tubular barrel (102) thereon, and at least one sliding foot (523) which extends radially and outwardly from said bearing wall (521) and which slidably abuts against said arcuate surface (27) of said second lateral wall (24), said operating portion (54) projecting from said accommodation space (26) through said arcuate slot (25) .
The dual cartridge caulking gun (100) as claimed in Claim 2, characterized in that said arcuate slot (25) is formed in said second lateral wall (24) and adjacent to said first end wall (21), said flat plate portion (51) being disposed adjoining and parallel with an inboard side of said first end wall (21) and being disposed within said accommodation space (26).
The dual cartridge caulking gun (100) as claimed in Claim 3, characterized in that said arcuate slot (25) has a lower end (251), an upper end (252) opposite to said lower end (251), and at least two round holes (253) interposed between said upper and lower ends (252, 251), said adjusting unit (50) including an adjusting piece (501) which has said flat plate portion (51) and said arcuate plate portion (52), a knob piece (502) which is rotatably connected to said adjusting piece (501) and has said operating portion (54), and a screw (503) which extends through said adjusting piece (501) and threadedly engages with said knob piece (502), said arcuate plate portion (52) further having a mount projection (526) which projects radially and outwardly from said bearing wall (521), said knob piece (502) further having a rotating portion (53) which is slidably inserted into said arcuate slot (25) and is journalled on said mount projection (526) to permit rotation of said knob piece (502) relative to said adjusting piece (501), said rotating portion (53) having two flat surface segments (531) diametrically opposite to each other, and two curve surface segments (532) each interposed between said two flat surface segments (531) and diametrically opposite to each other, a length between said curve surface segments (532) being larger than that between said flat surface segments (531) and being not larger than a diameter of said round holes (253) such that said rotating portion (53) is turnable between a retained position where said curve surface segments (532) are parallel to said arcuate slot (25) to be retained in one of said round holes (253), and a slidable position where said flat surface segments (531) are parallel to said arcuate slot (25) to permit sliding movement of said rotating portion (53) along said arcuate slot (25).
The dual cartridge caulking gun (100) as claimed in Claim 4, characterized in that said operating portion (54) has an inner end surface (541) facing said mount projection (526), and at least two retaining recesses (542, 543) formed in said inner end surface (541) and angularly spaced apart from each other, said mount projection (526) having at least one peg (527) which projects to engage in a selected one of said retaining recesses (542, 543) to retain said knob piece (502) to said adjusting piece (501), said adjusting unit (50) further including a biasing spring (504) which is disposed between said screw (503) and said adjusting piece (501) so as to bias said retaining recesses (542, 543) toward said peg (527).
The dual cartridge caulking gun (100) as claimed in Claim 2, characterized in that said bearing wall (521) has an outer wall surface (522) radially opposite to said first and second wall surface segments (524, 525), said arcuate plate portion (52) having two of said sliding feet (523) each of which projects from said outer wall surface (522) and is in form of a curve wedge rib having a curve edge (5231) that extends around said pivot pin (511).
The dual cartridge caulking gun (100) as claimed in Claim 2, characterized in that said penetrating slot (512) is elongated and round in shape and has a round first end portion (514) and a round second end portion (515) opposite to each other, the curvature center of said first wall surface segment (524) being located at a circle center of said first end portion (514), the curvature center of said second wall surface segment (525) being located at a circle center of said second end portion (515), a curvature of said second wall surface segment (525) being larger than a curvature of said first wall surface segment (524), said second plunger (32) being movable along said penetrating slot (512), and being actuated to push the second tubular barrel (102) when the second tubular barrel (102) is supported by said first wall surface segment (524) and has a larger diameter and said second plunger (32) is at said first end portion (514), and to push the second tubular barrel (102) when the second tubular barrel (102) is supported by said second wall surface segment (525) and has a smaller diameter and said second plunger (32) is at said second end portion (515).
The dual cartridge caulking gun (100) as claimed in Claim 2, characterized in that said plunger unit (30) further includes a crosspiece (34) which is connected between said first and second plungers (31, 32), said crosspiece (34) having an inner sliding hole (341.) which is aligned with the central line (L), and an outer sliding hole (342) which is in spatial communication with said inner sliding hole (341) along the central line (L), said outer sliding hole (342) having a width which is measured in an upright direction (Z) that is transverse to both the longitudinal direction (X) and the transverse direction (Y), and which is smaller than a width of said inner sliding hole (341) that is measured in the upright direction (Z), said second plunger (32) having a plunger rod (321) which extends along the central line (L) and through said outer sliding hole (342), said second hole (212) and said penetrating slot (512), and an enlarged end head (322) which extends transversely from an end of said plunger rod (321) and which is slidably disposed in said inner sliding hole (341), said plunger rod (321) having a width which is measured in the upright direction (Z) and which is smaller than a width of said end head (322) that is measured in the upright direction (Z), and being slidable in said outer sliding hole (342) in the transverse direction (Y).
The dual cartridge caulking gun (100) as claimed in Claim 8, characterized in that said end head (322) is integrally formed with said plunger rod (321), and said second plunger (32) has an L-shaped cross-section along the central line (L).
The dual cartridge caulking gun (100) as claimed in Claim 8, characterized in that said trigger unit (40) includes a trigger lever (41) pivotably connected to said gun body (10), an actuated block (42) sleeved on said first plunger (31) and disposed outwardly of said receptacle (20), a first biasing spring (43) disposed between said actuated block (42) and said receptacle (20), a returning presser (44) sleeved on said first plunger (31) and disposed between said gun body (10) and said crosspiece (34), and a second biasing spring (45) disposed between said gun body (10) and said crosspiece (34) such that said trigger lever (41) is pullable to actuate said actuated block (42) to move said first and second plungers (31, 32) toward inside of the first and second tubular barrels (101, 102), and said returning presser (44) is pressable to actuate returning movement of said first and second plungers (31, 32).