WO2022122106A1

WO2022122106A1 - Dispenser tool and robot with such tool

Info

Publication number: WO2022122106A1
Application number: PCT/DK2021/050362
Authority: WO
Inventors: Hicham ALI SAOUD; Magnus ÁRNASON
Original assignee: Onrobot A/S
Priority date: 2020-12-09
Filing date: 2021-12-09
Publication date: 2022-06-16
Also published as: EP4259343A1; DK180911B1; DK202001387A1

Abstract

A front-loaded dispenser tool (1) for dispensing viscous paste construction material from a cartridge (8) and an automated robot (21) for the tool (1). A pair of arms (7A, 7B) on opposite sides of an insertion opening (6A) for the cartridge (8) are arranged rotationally for reducing the size of the opening (6A) by the rotation and thereby locking the cartridge (8) inside the tool (1).

Description

Dispenser tool and robot with such tool

FIELD OF THE INVENTION

The present invention relates to a dispenser tool for a cylindrical dispenser cartridge, as used in caulking guns. The invention also relates to a robot with such dispenser tool.

BACKGROUND OF THE INVENTION

Caulking gun is a term used for a device that comprises a cylindrical container, for example a cylindrical tubular cartridge, containing a pasty substance and comprising a front-end nozzle for expelling the pasty substance as well as a piston that can be moved from the rear towards the front-end for pressing the pasty substance out through the nozzle. A typical pasty substance for which such guns are used is sticky repair paste or glue, for example silicone. For practical reasons and for ease of re-use, traditional caulking guns are loaded with replaceable one-time-use cartridges of the type as illustrated in FIG. 6, the cartridge having a nozzle 9 at the front-end of a cylindrical tube 8A and a piston 8B at the rear. Once loaded into the frame of the caulking gun, the piston 8B is pushed forward by an actuator, for example comprising a push rod, pressing on the piston for advancing the paste towards the front end and out of the nozzle 9. For manual operated caulking guns, a handle is squeezed manually for advancing the push rod. Alternatively, the piston of the cartridge is advanced by an electrically or pneumatically driven actuator. Examples are numerous in the prior art, ranging from simple manual devices to advanced models that are operated by a robot, for example as illustrated for repair of wind turbine blades in US patent applications US2017/239682 or US2020/238324.

Some types of caulking guns are front-loaded. Examples are disclosed in US3987939 and US6926177, in which the locking mechanism for securing the cartridge inside the gun comprises a front-end latch or cap that is pivotal between a lock orientation, in which the cartridge is held in place inside the gun by the latch or cap, and a release orientation, in which the latch or cap is pivoted away from the front end, and the cartridge can be inserted or taken out of the gun. For the front-loaded types, the operation of the locking and releasing is a simple operation when done manually. For example, in US3987939, the latch comprises two hinged arms that have to be squeezed towards each other when the latch is pivoted in or out of the locking orientation, and which upon release of the squeezing action lock into a recess and hold the cartridge in place by the arms extending around the nozzle and pressing against the front-end, largely along the rim of the cartridge.

This mechanism is not only difficult to operate manually but, also, and in particular, unsuitable for operation by a robot, as it requires simultaneous squeezing and pivoting of relatively thin resilient wires, which is highly complex even for automatic operation.

Another type of front-loaded caulking gun is disclosed in European patent application EP0092607, in which the cartridge is held in place by a plurality of arms, illustrated as 12 arms, which extend forward and which are resiliently moving sideways during insertion of the cartridge into the cavity and which, after insertion of the cartridge, are pressed towards the cartridge by sliding a sleeve forward around the arms so that inwardly extending projections of the arms are held around the front edge of the cartridge. This principle has a number of disadvantages in that the sleeve has a tendency to get stuck after a certain time of use and can be difficult to slide manually. For the same reason, the mechanism is relatively difficult to use in automated systems.

W020171610173A1 discloses abattery powered dispenser for one and two components foils and cartridges., The dispenser has a useful closing mechanism. The dispenser, however, is not well suited for operation by a robot.

Accordingly, for caulking guns, especially when operated by robots, there is a need for improvement.

DESCRIPTION / SUMMARY OF THE INVENTION

It is therefore an objective of the invention to provide an improvement in the art. In particular, it is an objective to provide an improved or alternative locking mechanism for cartridges in dispenser tools, in particular front-loaded caulking guns, especially when operated by a robot. A further objective is to provide a locking mechanism for such a dispenser tool, which is simple but efficient and easy and quick to operate, for example operated by a robot. These and further objectives will be explained in the following. One or more of the objectives is solved by a dispenser tool as described in the claims and in the following, in particular a robot-operated dispenser tool.

In short, with an offset in front-loaded caulking guns for dispensing viscous paste construction material from a cartridge, the dispenser tool comprises two rotationally arranged arms on opposite sides of an insertion opening for the cartridge and arranged for reducing the size of the opening by the rotation of the arms towards each other on and about a rotation axle and thereby locking the cartridge inside the tool.

Details are explained in the following.

The dispenser tool is front-loaded for receiving a cartridge into a cavity of a cartridge holder. It also comprises a dispenser actuator acting on the piston from the rear end of the cartridge, for pressing a viscous paste, typically sticky, as a construction material out of the cartridge for dispensing it onto a surface. For example, the paste is a glue or a filler material for surfaces, the surfaces being of various kind, including plane or curved surfaces, or formed as edges, slots, or recesses.

The cartridge comprises a rigid cylindrical tubular wall having a longitudinal cylinder axis and having a cartridge front and, oppositely, a cartridge rear. It comprises a nozzle at the front and a piston slidable inside the tubular wall. The piston is accessible from the rear for pushing towards the front end and thereby pressing the paste material out of the cartridge through the nozzle. Advantageously, the cartridge is of a standard type with specific standard dimensions and available with various contents of construction materials. Standard types are known as, for example, lOoz or 29oz cartridge types.

A front-load opening is provided at a front of the cavity for insertion of the cartridge into the cavity with the rear end of the cartridge being inserted through the opening and into the cavity first, after which the remaining part of the cartridge is inserted, until the cartridge is inside the cavity but not the nozzle, which is extending from the front end of the cartridge. After insertion, the cartridge is held in place by a locking mechanism at the cavity front for locking the cartridge inside the cavity and preventing the cartridge from being pressed out of the cavity when the actuator is pushing the piston towards the front end of the cartridge.

Typically, the cavity is elongate with a longitudinal cavity axis. When a cartridge is inserted, the cylinder axis of the cartridge is parallel with the longitudinal cavity axis.

The locking mechanism comprises a pair of arms with the two arms being arranged on opposite sides of the front opening for moving between a release state, in which the cartridge is movable through the front opening, and a locking state, in which the arms are blocking part of the opening and preventing the cartridge from leaving the cavity.

In comparison with some of the prior art, particularly EP0092607, it has been found useful that the locking mechanism has only two arms that are configured for blocking part of the opening and preventing the cartridge from leaving the cavity. Using only two arms yields a system that is simple to produce and simple and reliable in function.

Each of the arms is mounted rotationally on a rotation axle for toggling the arms between the release state and the locking state by rotation of the two arms about the axle. In particular contrast to the above-mentioned US3987939, the rotation axle is not perpendicular but parallel to a longitudinal axis of the cavity and parallel to the cylinder axis of the cartridge. Due to the axle and its orientation, the arms are arranged for toggling between the release state and the locking state by rotation of the two arms relatively to each other in opposite directions in a lateral plane perpendicular to the rotation axle.

Several possibilities exist for actuating the two arms, including various principles known from gripper tools where two arms are moved towards each other and away from each other, depending on whether the arms should go into a locking state or a release state. In the locking mechanism, similar principles apply, although the arms are not gripping the cartridge but are moved in front of the cartridge, thereby decreasing the passage in the opening and preventing the cartridge from moving out of the cavity. Optionally, the two arms are rotated on and about the same axle. Alternatively, each arm has its own axle.

In some practical embodiments, the two arms are arranged according to a scissor mechanism with an extension of each arm on the opposite side of the axle, the two extensions of the two arms forming opposite jaws, which when pressed apart move the pair of arms away from the opening to switch from the closed to the release state.

In order to move the arms in rotation about the axle or axles, a locking mechanism is provided with a lock actuator. In practical embodiments, the lock actuator comprises a mechanical switch that is accessible on an outer side of the lock module and which when activated manually or by the arm of a robot rotates the arms into a release orientation.

Optionally, an actuator part in mechanical extension of the switch is arranged between the jaws for by translation or rotation of the switch correspondingly translating or rotating the actuator part and thereby mechanically pressing the opposite jaws apart by the actuator part.

For example, in order to move the jaws apart, the actuator part is elongate, for example elliptical, or comprises a cam, for pressing the jaws apart by rotation.

In some concrete embodiments, the actuator part is conical with a symmetry axis and with a linear direction of movement along the symmetry axis. The conical actuator part is configured for pressing the jaws by the movement. In practical embodiments, the conical part is located between the jaws and only a portion of it is abutting the jaws for pressing the jaws apart by movement of the conical part from a first position, in which a narrow portion of the actuator part is located between the jaws, to a second position, where a wider portion of the conical part is abutting the jaws and pressing them apart (from each other).

Optionally, the switch is a press-activated button and provided in linear extension of the actuator part and arranged for pushing the actuator part along the symmetry axis by press on the button. Advantageously, the actuator part, be it translational or rotational, is pre-stressed against activation by a return spring.

Optionally, as an alternative or in addition to the spring force that pre-stresses the actuator part, the locking mechanism comprises a return spring arrangement with at least one return spring in mechanical contact with the pair of arms and acting on the pair of arms for prestressing the pair of arms into the locking state. For example, the return spring arrangement comprises two return springs, each one acting on one arm, or particularly on one of the jaws for pre-stressing the jaws together.

It has been found useful that the arms are curved in the lateral plane to extend along opposite portions of the rim of the opening. The arms, when in locking state, are oriented such that they are positioned against the front end or just at the front end of the cartridge to secure it inside the cavity.

Advantageously, each of the arms has a rear side towards the cavity and an opposite front side, wherein the rear side is arranged for abutting the front end of the cartridge and locking the cartridge in the cavity. For example, the rear side is flat and perpendicular to the cavity axis and, thus, also perpendicular to the cylinder axis of the cartridge. However, optionally, the rear side is inclined inwards and backwards towards the rear of the cavity for acting as a hook against the front end of the cartridge.

Optionally and for ease of insertion of the cartridge by its rear end, the front side of the bent arms is inclined towards the central axis and towards the rear of the cavity in order to press the arms apart by the rear end of the cartridge when the cartridge is inserted into the cavity through the opening. In this case, it is not necessary to force the arms into an open state before the cartridge is inserted into the cavity, as the rear end of the cartridge at contact with the front side of the bent arms is pressing on the inclined front side of the arms and thus exerting also a lateral force on the arms, which when overcoming any pre-stressing force, such as spring force, move laterally away from the opening due to the exerted force and give way for insertion of the cartridge.

The fact that the arms extend laterally to the cavity axis and the pressing has to overcome the pre-stressing spring only, causes that the action of pressing the arms apart during insertion of the cartridge requires much less force than in the system of the aforementioned EP0092607. In EP0092607, 12 parallel extending arms act as springs and have to be pushed aside against their internal resiliency, in addition to the fact that a sleeve is arranged to keep the arms in place. Accordingly, the principle as described herein is more user-friendly and faster with respect to reloading a cartridge into the cavity.

Such a dispenser tool with its cartridge holder is suitably held by a robot arm of a robot. Optionally, the robot arm comprises an extension that is configured for activating a release button or release lever of the locking mechanism. In the latter case, the simple mechanical principle of the locking mechanism and its ease of use for release of the cartridge from the cavity is an advantage, as the programming of the robot arm or its extension can be made simple, especially when the locking mechanism is deactivated by a press button or rotational button or lever.

SHORT DESCRIPTION OF THE DRAWINGS

The invention will be explained in more detail with reference to the drawings, where FIG. 1A illustrates a front-end of a dispenser tool;

FIG. IB illustrates the operation of loading a cartridge into the cavity of the dispenser tool,

FIG. 1C illustrates the dispenser tool when a cartridge is inserted;

FIG. 2 is an enlarged, semi-transparent view of the front mount of the dispenser tool, FIG. 3A is a view into the lock module in the locking state;

FIG. 3B is a view into the lock module in the unlocked, release state;

FIG. 4A illustrates details of the locking mechanism in locking state;

FIG. 4B is a perspective view of the locking mechanism;

FIG. 4C is a perspective view of the locking mechanism from an opposite perspective;

FIG. 5 illustrates details of the locking mechanism in unlocked, release state;

FIG. 6 illustrates the dispenser tool attached to a robot arm;

FIG. 7 illustrates a prior art dispenser cartridge for a caulking gun. DETAILED DESCRIPTION / PREFERRED EMBODIMENT

FIG. 1A illustrates a drawing of a dispenser tool 1 with a front-load mechanism for a dispenser cartridge 8. The dispenser tool 1, functioning as a caulking gun, comprises a cartridge holder 2 that has a cavity 6 into which the cartridge 8 can be inserted.

For example, the cartridge 8 may be of the type as illustrated in FIG. 6 with a nozzle 9 and a piston 8B arranged slidably inside a tubular wall 8A for pressing viscous paste out of the nozzle 9 when advanced towards the nozzle 9. Optionally, the cartridge is of a standard type, which is commonly used in caulking guns. The dimensions of the dispenser tool are not limited to any particular size and can equally well be constructed for various sizes of cartridges, for example standard cartridges of the lOoz or 29oz types.

The cartridge 8 is inserted into the cavity 6 and slides past a locking mechanism 5, which is arranged in a lock module 4 mounted on a front mount 3. The locking mechanism 5 is configured for locking the cartridge 8 inside the cavity 6 so that the cartridge 8 is not pressed out of the cavity 6 when an actuator pushes the piston 8B forward towards the nozzle 9.

For holding the cartridge 8, a pair of arms 7 lock the cartridge 8 in place. This pair of arms 7 and the locking mechanism 5 are described in greater detail with reference to FIG. 2, which is a semi-transparent view of the lock module 4, and FIG. 3, which shows a view into the lock module 4 from the rear side.

As illustrated in FIG. 2 and FIG. 3A, and in better detail in FIG. 4A, each of the two arms 7A, 7B is hinged in a rotation axle 18 for rotation about the axle 18. In extension of the first arm 7A and in extension of the second arm 7B, respectively, a first jaw 14A and a second jaw 14B are provided. The pair of arms 7 and the pair of jaws 14 function according to a scissor principle due to the rotation axles 18.

Between the pair of jaws 14, a conical actuator part 13B of a lock actuator 13 is provided. Moving the conical actuator part 13B in one direction along a central axis 13D of the conical actuator part 13B squeezes the jaws 14A, 14B apart, which is illustrated in FIG 3B and FIG. 5. In order to advance the lock actuator 13, a press button 13A is pushed against the force of a helical counter- spring 16, which extends around a guiding rod 13C, the latter being held in stabilized orientation in a corresponding bearing in a socket 22 in the lock module 4, as illustrated in FIG. 2.

When a pressing force on the press button 13A of the actuator part 13 is released, the conical actuator part 13B moves back, and the jaws 14A, 14B as well as the arms 7A, 7B are returning to a close orientation. Return springs 15 are pressing on the jaws 14A, 14B in order to provide a force on the jaws 14A, 14B in a direction towards the actuator part 13B.

Best illustrated in FIG. 4A, the jaws 14A, 14B are advantageously provided with an inclined contact surface that is abutting the conical actuator part 13B. The contact surface may further be bent so that the shape of the contact surface 23 follows the conical actuator part 13B and provides an easy sliding and minimal wear on the conical actuator part 13B.

As illustrated in FIG. 4B, the arms 7A, 7B have a front side 17A, which is inclined, optionally conically inclined. The front side 17A is directed outwards from the cavity 6 so that insertion of a cartridge 8 into the cavity 6 contacts the inclined front side 17A and pushes the arms 7A, 7B apart during advance of the back end of the cartridge 8 in the direction into the cavity 6.

As illustrated in FIG. 4C, the arms 7A, 7B have a rear side 17B that is oriented towards the cavity 6 and which is flat in a plane perpendicular to the rotational axle 18. The flat rear surface 17B secures the cartridge inside the cavity. When a cartridge 8 is inserted into the cavity 8 by pressing the arms apart 7A, 7B, the arms 7A, 7B will return to their original spring-loaded rest-position as soon as the front of the cartridge 8 passed the pair of arms 7.

It has been found useful that each of the arms 7A, 7B is shaped as a circular arch, spanning more than 90 degrees of a circle. Both arms in combination, thus, hold against the circular front end of the cartridge by more than half of its circumference, resulting in a stable securing action. As illustrated, the movements of the arms 7A, 7B and the jaws 14A, 14B are only in a plane perpendicular to the rotation axles 18 for the pair of arms 7 and the pair of jaws 14, as well as perpendicular to a longitudinal axis of the cavity 6 and perpendicular to a longitudinal axis of the rotational symmetric cylindrical tubular cartridge 8. This two- dimensional rotational movement only in a single plane makes the locking principle simple and efficient at the same time.

FIG. 6 illustrates a dispenser tool 1 with a cartridge holder 2 as described above and which further comprises an actuator 19 that extends inside the cavity 6 and interacts with the piston 8B of the cartridge 8 for advancing the piston from the rear towards the nozzle 9 and thereby pressing paste out of the nozzle 9 of the cartridge 8.

Advantageously, the dispenser tool 1 is held by an arm 20 of a robot 21. From the robot arm 20, an extension 23, which is only shown stylistically in FIG. 6, connects to the press button 13 A for pressing it to operate the lock actuator 13 in case the cartridge 8 shall be released from the dispenser tool 1 and removed from the cavity 6.

In the shown embodiment, the lock actuator 13 is illustrated as a press button with a linear movement. Alternatively, the lock actuator is rotational and is formed with a cross section that is elliptical when measured in a plane perpendicular to its longitudinal axis. Rotating such elliptical lock actuator would move the jaws back and forth depending on the orientation of the ellipse. As a further alternative for a rotational lock actuator, it may be provided with cams that press the jaws apart when the lock actuator is rotated about the longitudinal axis. A press button for actuation by being pressed is a simple mechanism for a robot. However, a rotation of a lever or button is equally simple. In the latter case, the button would typically have a connector for controlling the rotation, for example similar to a prior art screw head, including one of a variety of slots for receiving a male screwing tool or one of a variety of heads with an edged circumference for being rotated by a corresponding female tool gripping around the cooperating head.

The invention is simple to produce and use, takes up little space in the longitudinal direction, and is efficient for rapid exchange of one-time-use cartridges. List of reference numerals

1 - Dispenser tool

2 - Cartridge holder

3 - Front mount

4 - Lock module

5 - Locking mechanism

6 - Cavity for cartridge 8

7 - Pair of arms of locking mechanism 5 for locking the cartridge inside the cavity 6

7A - First arm

7B - Second arm

8 - Cartridge

8 A - Tubular wall of cartridge 8

8B - Piston in cartridge 8

8C - Cylinder axis

9 - Nozzle

10 - Flange of front mount 3

11 - Screw holes in flange 10

12 - Screw canal

13 - Lock actuator of locking mechanism 5

13A - Press button of lock actuator 13

13B - Actuator part of lock actuator 13

13C - Guiding rod of lock actuator

13D - Longitudinal axis of the lock actuator 13

14 - Jaws of locking mechanism 5

14A - First jaw

14B - Second jaw

15 - Return spring for jaws 14

16 - Return spring for lock actuator 13

17A - Inclined front sides of arms 7

17B - Flat rear sides of arms 7

18 - Rotation axle for arms 7

19 - Dispenser actuator

20 - Robot arm

21 - Robot 22 - Socket in lock module 4 with bearing for guiding rod 13C

23 - Extension of robot arm 20

Claims

1. A front-loaded dispenser tool (1) for dispensing viscous paste construction material onto a surface, wherein the dispenser tool (1) comprises an elongate cavity (6) having a longitudinal cavity axis (6B) and being configured for receiving and holding a cylindrical dispenser cartridge (8) having a front nozzle (9) and rear-operated piston (8B), wherein the cavity (6) has an opening (6A) at a cavity front for insertion of the cartridge (8) into the cavity (6) with the rear end of the cartridge (8) being inserted through the opening (6a) and into the cavity (6) first; wherein the dispenser tool (1) comprises a dispenser actuator (19) configured for driving the piston (8B) from a cavity rear towards the nozzle (9), wherein the dispenser tool (1) at the opening (6 A) comprises a locking mechanism (5) that comprises a pair of arms (7) having its two arms (7A, 7B) arranged on opposite sides of the opening (6A), and wherein each of the two arms (7A, 7B) is mounted rotationally on a rotation axle (18), and wherein the locking mechanism (5) is configured for rotationally toggling the two arms (7A, 7B) between a locking state, in which the two arms (17A, 17B) are blocking part of the opening (6A) for preventing the cartridge (8) from leaving the cavity (6), and a release state, in which the cartridge (8) is freely movable through the opening (6A), wherein the rotation axle (18) for each of the arms (7A, 7B) is parallel to a longitudinal axis (6B) of the cavity (6) and the two arms (7A, 7B) are arranged for toggling between the release state and the locking state by rotation of the two arms (7A, 7B) in opposite directions in a lateral plane perpendicular to the rotation axle (18), where the locking mechanism (5) has only two arms (7A, 7B) that are configured for blocking part of the opening (6A) and preventing the cartridge (8) from leaving the cavity (6), characterised in that the two arms (7A, 7B) are arranged as a scissor mechanism with an extension on each of the two arms (7A, 7B) on the opposite side of the axle (18), the two extensions of the two arms (7A, 7B) forming opposite jaws (14A, 14B) which when pressed apart move the pair of arms (7) apart for switching from the locking state to the release state; wherein the locking mechanism (5) comprises a lock actuator (13) that comprises a movable switch (13A), accessible from outside the cavity (6), and an actuator part (13B) in mechanical extension of the switch (13 A) and arranged between the jaws (14A, 14B) for by movement of the switch (13 A) causing corresponding movement of the actuator part (13B) and mechanically pressing the opposite jaws (14A, 14B) apart by the movement of the actuator part (13B).

2. Dispenser tool according to claim 1, wherein the actuator part (13B) is conical with a symmetry axis (13D) and with a linear direction of movement along the symmetry axis (13D), wherein the conical actuator part (13B) is configured for pressing the jaws (14A, 14B) apart by the movement.

3. Dispenser tool according to claim 2, wherein the switch (13 A) is a press-activated button and provided in linear extension of the actuator part (13B) and arranged for pushing the actuator part (13B) along the symmetry axis by press on the button, wherein the actuator part (13B) is pre-stressed against the press by a return spring (16).

4. Dispenser tool according to any preceding claim, wherein the locking mechanism (5) comprises a return spring arrangement with at least one return spring (15) in mechanical contact with the pair of arms (7) and acting on the pair of arms (7) for prestressing the pair of arms (7) into the locking state.

5. Dispenser tool according to claim 4, wherein the return spring arrangement comprises two return springs (15), each one acting on one of the jaws (14A, 14B) for pre-stressing the jaws (14A, 14B) together.

6. Dispenser tool according to any preceding claim, wherein the arms (7A, 7B) are curved in the lateral plane to extend along opposite portions of the rim of the opening (6A), wherein each of the arms (7A, 7B) has rear side (17B) towards the cavity (6) and an opposite front side (17A), wherein the rear side (17B) is arranged for abutting the front end of the cartridge (8) and locking the cartridge (8) inside the cavity (6), and wherein the front side (17A) is inclined towards the longitudinal axis (6B) of the cavity (6) and towards the rear of the cavity (6) in order for the arms (17A, 17B) to be pressed apart by the rear end of the cartridge (8) when the cartridge (8) is inserted into the cavity (6) through the opening.

7. An automated robot (21) comprising a robot arm (20) holding a dispenser tool (1) according to anyone of the preceding claims. 15

8. Robot according to claim 7, wherein the robot arm (20) comprises an extension (23) configured for operating the locking mechanism (5).