Hand extruder, in particular for welding components made of plastic

Abstract

A hand extruder, particularly for welding parts made of plastic, has a main body supporting an extrusion device for extruding plastic material, an actuation device for actuating the extrusion device, a heating device for heating the plastic material, a preheating device for preheating the parts to be welded, and a control device for controlling the hand extruder; a grip member removably connected to the main body by an interconnection device, which is predisposed to pass from a coupling configuration, in which the grip member is coupled to the main body, to a decoupling configuration, in which the grip member is decoupled from the main body; the interconnection device has an electrical fitting device of the plug-socket type, which electrically and removably connects at least part of the devices supported by the main body to electrical control devices arranged on the grip member.

Description

Technical Field

[0001] The invention relates to a manual extruder, in particular for welding components made of plastic. Background Art

[0002] Manually operated portable extrusion welding units, known as "hand extruders", are generally used to weld objects such as pipes, sheets and films by adding thermoplastic material.

[0003] Manual extruders generally have a screw extrusion system actuated by an electric motor and fed by a suitable system for feeding the added material.

[0004] The manual extruder has a system for heating the added material and a system for preheating the parts to be welded.

[0005] EP1637234A1 discloses a handheld extrusion welding device having a housing with a cooling member whose air inlet is located on the side of the extruder screw. The cooling member is configured as a central supporting base member for holding the housing wall, drive system, screw cylinder and hot air unit.

[0006] JP2000225082A discloses a vacuum cleaner and a suction port assembly, comprising a vacuum cleaner body, a suction nozzle, a hand handle, a connecting pipe, and a suction port body. The hand handle is provided with a switch for releasing a fixing device of a first pipe body and for fixing the sliding of a second pipe body.

[0007] DE 3131695 A1 discloses a screw extruder for welding thermoplastics and having a heating device controlled by a temperature sensor. A switch-on inhibit is provided for the screw drive motor, which can only be canceled when the heating air is heated within a predetermined temperature range and the melting chamber is heated within a predetermined temperature range.

[0008] EP 0 594 889 A1 discloses a welding device for processing thermoplastic materials, comprising a heatable conveying chamber, a drive for a conveying element and an air heater for preheating air; the drive is also coupled to a fan arranged axially in series for supplying the air heater.

[0009] In the most common form, substantially all of the aforementioned components are combined into a single body that is provided with a grip, the primary purpose of which is to facilitate user manipulation of the manual extruder.

[0010] However, manual extruders are often used in confined spaces or particularly awkward positions, in which case the grip constitutes a space-consuming element that restricts and constrains the user rather than facilitating his or her work. Summary of the Invention

[0011] The object of the present invention is to provide a manual extruder, in particular for welding components made of plastics material, which overcomes the disadvantages of the cited prior art.

[0012] Within the scope of this aim, a particular object of the invention is to provide a manual extruder the size of which can be reduced while maintaining functionality and reliability.

[0013] Another object of the present invention is to provide a manual extruder that is lightweight, practical to operate, and efficient from an operability standpoint.

[0014] Another object of the present invention is to provide a manual extruder that can provide maximum reliability and safety in use due to its special structural characteristics.

[0015] Yet another object of the present invention is to provide a manual extruder that is highly versatile and competitive from an economic point of view.

[0016] This object and these purposes, as well as other purposes that will become apparent hereinafter, are achieved, as claimed, by a manual extruder, in particular for welding components made of plastic. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Other characteristics and advantages will become more apparent from the description of a preferred but non-exclusive embodiment of the hand extruder of the invention, illustrated by way of non-limiting example in the accompanying drawings, in which:

[0018] Figure 1 is a perspective view of a manual extruder according to the present invention in a decoupled configuration;

[0019] Figure 2 is a perspective view of a manual extruder according to the present invention in a coupled configuration;

[0020] Figure 3 is a perspective view of the manual extruder according to the present invention in another coupled configuration;

[0021] Figure 4 is a perspective view showing the coupling operation of the manual extruder;

[0022] Figure 5 is a perspective view of the manual extruder in a coupled configuration;

[0023] Figure 6 is a perspective view of the manual extruder in a decoupled configuration;

[0024] Figure 7 is a perspective view of the manual extruder in another decoupled configuration;

[0025] Figure 8 is an exploded perspective view of a manual extruder according to the present invention;

[0026] Figure 9 It is a partially cutaway stereoscopic view of a manual extruder;

[0027] Figure 10 is a longitudinal sectional view of a manual extruder according to the present invention. DETAILED DESCRIPTION

[0028] With reference to the cited figures, a manual extruder according to the invention is indicated generally by the reference numeral 1 and comprises a body 2 forming a cavity 3 .

[0029] In the example shown, the body 2 has a generally oval shape.

[0030] The main body 2 is preferably composed of two half shells 2a and 2b, for example made of plastic, and detachably coupled to each other.

[0031] The upper area of ​​the manual extruder 1 is provided with a movable hook 4, for example for fastening a shoulder strap. The movable hook 4 is located in the space occupied by the main body 2 and is in an inactive position.

[0032] A lighting device 5 , preferably in the form of a ring, is provided on the front of the manual extruder 1 , ie the portion facing the component to be welded during use.

[0033] The cavity 3 at least partially accommodates an extrusion device 10 for extruding plastic material, an actuating device 20 for actuating the extrusion device 10 , a heating device 30 for heating the plastic material, a preheating device 40 for preheating the parts to be welded and a control device 50 for controlling the manual extruder 1 .

[0034] In the specific case, the extrusion means 10 preferably take the form of a single-screw extruder 11 , which essentially consists of a screw, not shown, which rotates with a very precise fit inside a cylindrical body 12 protruding from the front of the body 2 .

[0035] The single screw extruder 11 heats the raw material to a melting point and extrude the raw material, preferably polymer filaments, with the aid of a heating device 30. The polymer filaments are introduced into the single screw extruder 11 through a feed port 13.

[0036] Extrusion of the molten plastic material takes place at an outlet nozzle 14 arranged at an axial end of the cylinder 12 , providing a weld bead on / between the parts to be welded.

[0037] The heating device 30 may, for example, be constituted by a substantially helical resistor which is mounted coaxially with the cylindrical body 12 .

[0038] The actuating device 20 is axially mounted on the single-screw extruder 11 and, in a specific case, is constituted by a first electric motor 21 and a transmission member 22 interposed between the electric motor and the single-screw extruder 11 .

[0039] The preheating device 40 preferably includes a fan 41 rotated by a second motor 42 .

[0040] The fan 41 draws in external air through the opening 6 provided in the main body 2 and guides the air onto the electric heating resistor 43 .

[0041] In the specific case, the resistor 43 is formed by a litz wire, for example made of nickel-chromium, wound on a heat-resistant support 44 and mounted coaxially with the cylinder 12 .

[0042] The sucked-in air jet is heated by the resistor 43 and then blown onto the parts to be welded via the opening 45 , this air jet being fed by a cylindrical duct 46 arranged coaxially on the support 44 .

[0043] The manual extruder 1 is controlled by a control device 50 consisting of an electronic board managed, for example, by a microprocessor.

[0044] The control device 50 controls, in particular, the operating temperature and time of the heating device 30 for heating the plastic material and the preheating device 40 for preheating the parts to be welded.

[0045] It is obvious to a person skilled in the art that, depending on specific requirements, the body 2 , the extrusion device 10 , the actuation device 20 , the heating device 30 , the preheating device 40 and the control device 50 may be different from those shown and described, but technically equivalent thereto.

[0046] According to the present invention, the manual extruder 1 includes a grip 60, 160, which is detachably connected to the main body 2 via an interconnection device 70, 170, and the interconnection device 70, 170 is preset to enter a decoupling structure in which the grip 60, 160 is mechanically and functionally connected to the main body 2 from a connection structure in which the grip 60, 160 is mechanically and functionally connected to the main body 2.

[0047] The interconnection means 70 , 170 have a male-female mechanical cooperation means, which in certain cases is constituted by a coupling portion 71 protruding downwards from the body 2 and a corresponding coupling seat 72 , 172 formed on the gripping member 60 , 160 .

[0048] The coupling portion 71 and the coupling seat 72 , 172 preferably have a substantially Ω-shaped cross-section that allows them to slide fit along the coupling / decoupling direction 80 .

[0049] In more detail, the coupling portion 71 has a peripheral edge 73 that is at least partially complementary to the peripheral edge 74 , 174 of the coupling seat 72 , 172 and is configured to adhere thereto in the coupled configuration.

[0050] Those skilled in the art will recognize that the arrangement of the coupling portion 71 and coupling seats 72, 172 described herein is merely one example, and that many other shapes and sizes are possible without departing from the present invention.

[0051] Advantageously, the mechanical cooperation means also comprise a locking element 75 associated with the body 2 so as to be able to translate therewith, and a corresponding recess 76 , 176 formed on the gripping element 60 , 160 .

[0052] The locking element 75 is movable in a locking / unlocking direction transverse to the coupling / uncoupling direction 80 and, in the coupled configuration, projects from the coupling portion 71 into engagement with a recess 76 , 176 arranged in the coupling seat 72 , 172 .

[0053] In this way, the transition from the coupled configuration to the decoupled configuration is only possible when the locking element 75 is disengaged from the recess 76 , 176 .

[0054] A button 77 protruding downwards from the body 2 allows the unlocking movement of the actuating locking member 75 to be activated.

[0055] Resilient contrast means, not shown in the figures, act on the button 77 and, during the transition from the uncoupled configuration to the coupled configuration, move the locking element 75 so as to bring it into engagement with the recess 76 , 176 automatically or by a quick movement.

[0056] In contrast, in the coupled configuration, the elastic contrast means keep the locking element 75 in continuous engagement with the recess 76 , 176 .

[0057] In addition to the mechanical mating means, the interconnection means 70, 170 also include electrical mating means, for example of the multi-pole plug / socket type, which allow at least some of the electrical components of the manual extruder 1 supported by the main body 2 to be electrically connected in a detachable manner to the electrical control means arranged on the grip 60, 160.

[0058] The electrical control device comprises at least one on / off button 7, 107 and a control member 8, 108 for adjusting the speed of the actuating device 20, however, it is obvious to a person skilled in the art that the electrical control device may also comprise other types of devices according to specific requirements.

[0059] By way of example, the electrical mating device is constituted by a female member 78 arranged on the body 2 , preferably on the rear of the coupling portion 71 , and a male member 79 , 179 arranged on the grip 60 , 160 , preferably on the rear of the coupling seat 72 , 172 .

[0060] In this manner, the male member 79, 179 and the corresponding female member 78 may be connected to the coupling portion 71 and the corresponding coupling seat 72, 172 substantially simultaneously during the transition from the decoupled configuration to the coupled configuration.

[0061] In the first embodiment, the grip 60 substantially has the shape of a handle 61 extending transversely to the coupling / uncoupling direction 80 and provided with a portion of the interconnection means 70 .

[0062] A power on / off button 7 and a speed adjustment control 8 are arranged on the front of the handle 61 to allow the user to operate the manual extruder 1 in a completely known manner.

[0063] In the second embodiment, the gripping piece 160 substantially has the shape of a plate 161 extending substantially parallel to the coupling / decoupling direction 80 so as to have a limited spatial footprint.

[0064] In the drawings, components of the grip 160 that are identical and / or equivalent to components of the grip 60 are indicated by the same reference numerals increased by 100.

[0065] The rear portion of the plate 161 is provided with a power on / off button 107 and a speed adjustment control 108 , which has a curvature that facilitates ergonomic grip and also functions as a user manipulating the manual extruder 1 by gripping its entire body 2 in this case.

[0066] The use of the hand extruder according to the invention is apparent from the above description.

[0067] In particular, under normal working conditions, where the available space is sufficiently large, the operator can use the grip 60 which, by means of the handle 61 , ensures excellent operability of the manual extruder 1 .

[0068] If, on the other hand, the operator has to work in a confined space or in a particularly awkward position, the grip 60 can be replaced by a grip 160 which, by means of the plate 161 , makes the hand extruder 1 very compact from a structural and spatial point of view and at the same time makes it optimally grippable from an ergonomic point of view.

[0069] To remove the handle 61 , the user simply presses the button 77 , moves the locking element 75 out of the recess 76 , 176 , and then slides the grip 60 in the coupling / uncoupling direction 80 until it is completely separated from the body 2 .

[0070] To mount the plate 161 , the user must simply insert the coupling portion 71 into the corresponding coupling seat 172 and slide the grip 160 in the coupling / uncoupling direction 80 until the elastic contrasting means move the locking element 75 so that it automatically, i.e. by a quick movement, engages the recess 176 .

[0071] By repeating these steps in reverse order, it will be apparent that grip 60 may be substituted for grip 160 .

[0072] In practice, it has been found that the invention achieves the intended aim and objects, providing a manual extruder allowing a reduction in space occupation while maintaining unchanged functionality and reliability.

[0073] Furthermore, the manual extruder according to the present invention is lightweight, practical to maneuver and efficient from an operational point of view.

[0074] Another particularly advantageous aspect of the invention is that the manual extruder itself is very versatile and can be used in different situations without having to carry out complex adaptation operations.

[0075] Yet another advantage of the manual extruder according to the invention is the complete safety and reliability of the grip coupling / decoupling system.

[0076] The materials used, as well as the dimensions, may be any according to requirements and the state of the art.

[0077] This application claims the benefit of Italian Patent Application No. 102020000017731, filed on July 22, 2020, the subject matter of which is incorporated herein by reference.

Claims

1. A manual extruder for welding parts made of plastic material, the manual extruder comprising: a main body supporting an extrusion device for extruding the plastic material, an actuation device for actuating the extrusion device, a heating device for heating the plastic material, a preheating device for preheating parts to be welded, and a control device for controlling the manual extruder; A gripping member, the gripping member being detachably connected to the main body via an interconnection device, the interconnection device being preset to enter a decoupling configuration in which the gripping member is coupled to the main body from a coupling configuration in which the gripping member is coupled to the main body; the manual extruder is characterized in that the interconnection device includes a plug-and-socket type electrical matching device, the electrical matching device electrically and detachably connecting at least a portion of the device supported by the main body to an electrical control device arranged on the gripping member, The holding member has a plate shape, and the plate extends parallel to the coupling / decoupling direction.

2. The manual extruder according to claim 1, characterized in that The interconnection means comprises mechanical engagement means which removably connects the grip to the body.

3. The manual extruder according to claim 2, characterized in that The mechanical engagement device comprises at least one coupling portion protruding from one between the body and the gripping member and at least one corresponding coupling seat formed on the other between the body and the gripping member.

4. The manual extruder according to claim 1, characterized in that The at least one coupling portion is slidably engaged with the at least one coupling seat along a coupling / decoupling direction.

5. The manual extruder according to claim 1, characterized in that The at least one coupling portion and the at least one coupling seat have an Ω-shaped cross section.

6. The manual extruder according to claim 2, characterized in that The mechanical mating device includes a locking member and at least one corresponding recess, wherein the locking member is associated with one between the main body and the holding member so that it can move along the locking / unlocking direction, and the at least one corresponding recess is formed on the other between the main body and the holding member, and when the locking member is disengaged from the recess, it can transition from the coupling structure to the decoupling structure.

7. The manual extruder according to claim 6, characterized in that The manual extruder comprises a button for actuating the locking member and elastic contrast means for maintaining the locking member in engagement with the recess in the coupled configuration.

8. The manual extruder according to claim 6, characterized in that The locking / unlocking direction is transverse to the coupling / uncoupling direction.

9. The manual extruder according to claim 1, characterized in that The electrical control means includes at least one on / off button and a control for adjusting the speed of the actuating means.

10. The manual extruder according to claim 1, characterized in that The electrical mating device includes at least one male member disposed on one between the body and the grip, and at least one corresponding female member disposed on the other between the body and the grip.

11. The manual extruder according to claim 1, characterized in that The at least one male member is slidably engaged with the at least one female member along the coupling / decoupling direction.

12. The manual extruder according to claim 3, characterized in that The at least one male member and the at least one female member of the electrical mating device are adapted to be simultaneously connected to at least one coupling portion and at least one coupling seat of the mechanical mating device during transition from the decoupled configuration to the coupled configuration.

13. The manual extruder according to claim 1, characterized in that The gripping member includes a portion shaped like a handle and extending transversely to the coupling / uncoupling direction.

14. The manual extruder according to claim 1, characterized in that The gripping member includes a plate-shaped portion extending parallel to the coupling / decoupling direction.

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