RU2141922C1 - Seam sealing syringe and holder preventing leakage after delivery - Google Patents

Abstract

FIELD: mechanical engineering. SUBSTANCE: holder has tubular body, front pressure hole in front part of tubular body and rear wall installed for displacement inside tubular body. Seam sealing syringe has pan for placing holder and piston installed for displacement parallel to pan. Control lever is used to move rear wall inside tubular body forward to decrease volume of chamber in holder. Rear wall is free to slide inside tubular body owing to reduced diameter of rear wall relative to inner diameter of tubular body. Wall starts moving/backwards when volume of body decreases in radial direction after operation. As an alternative, holder body can be protected from expansion and can be positively clamped . EFFECT: prevention of leakage of sealing compound caused by reduction of body volume. 10 cl, 9 dwg

Description

 The invention relates to joint sealing syringes and to discharge cartridges and, in particular, to the type of complex blowers in which the cartridge is inserted into the syringe and the piston moves the plunger from the back of the cartridge forward, thereby reducing the internal space of the cartridge intended for the sealing composition, and squeezes the composition from an open tip located on the front of the cartridge.

 Syringes for sealing seams of this type have a drawback - unwanted leakage of the composition, that is, increased pressure still remains in the internal cavity of the cartridge, despite the fact that the plunger has already stopped moving forward and, as a result, additional amounts of the composition are squeezed out.

 Two main causes of leakage are recognized. Firstly, an ordinary thin-walled cartridge tends to expand during the operation of the plunger, and according to the law of physics, such systems always tend to relax and return to their original position. After stopping the movement of the plunger, the voltage of the wall of the cartridge weakens. Due to the fact that the back walls of cartridges in modern devices are designed in such a way as to maintain their forward position, and given that the syringe plunger for sealing the seams is usually stopped in order to prevent movement in the opposite direction, the relaxation of the cartridge wall leads to leakage, i.e. leakage through the discharge tip. Secondly, most sealing compositions have a high degree of viscosity and, at least, have low compressibility, which creates significant internal pressure during the operation of the plunger, which, after stopping the plunger, also leads to leakage of the composition through the discharge tip.

 In the context of the prior art, the aforementioned leakage problem is solved by quickly releasing the syringe plunger to seal the seams and push it back as soon as the necessary amount of composition has been squeezed out.

 In US Pat. No. 5,236,105, Geylex proposes a new system for preventing the release of a composition. In his system, ordinary syringes for sealing joints are modified by the introduction of several elements, namely: a female element, a male element, a return spring and a stopper. The spring is used as a forced action element that vigorously pulls the rear wall in the cartridge back and thus creates a relative vacuum inside the cartridge.

 In U.S. Patent No. 4,834,268, Kepler describes a plunger system in which an elastic o-ring abuts against the inner wall surface of a cartridge of a radial component of force that presses the plunger to move forward in the discharge mode. When the plunger stops moving, the o-ring loosens slightly and allows the plunger to reduce the internal pressure in the cartridge.

 The first of the above methods to prevent leakage is clearly unsatisfactory. The systems described in the two above patents are quite complex and therefore overly expensive.

 The aim of the invention, respectively, is to present a syringe and cartridge for sealing seams to prevent leakage after injection, which will eliminate the disadvantages of prior art devices and methods of this general type. The main goal is to develop a simple and inexpensive system that can be applied to a wide range of cartridges and syringes for sealing seams and which reliably prevents leakage and discharge of the composition.

 Considering the above and other purposes, in accordance with the invention, an improved weld sealing cartridge is provided which is of a type having mainly a tubular body, a front discharge opening on the front of the tubular body, a rear wall that can be moved inside the tubular body, a tubular body, having a wall with an inner surface of the wall defining the inner diameter of the tubular body, and a tubular body defining a size of the chamber bounded by this inner surface th walls, front part and back wall. The improvement is determined by the fact that the diameter of the back wall is smaller than the inner diameter of the tubular body for sealing the seams, and basically an free annular gap is determined between the inner surface of the wall and the contour of the back wall.

 In accordance with an additional feature of the invention, the gap may be at least 0.2 mm and may exceed 1.0 mm.

 In accordance with another feature of the invention, spacer protrusions are formed on the periphery of the rear wall in contact with the inner surface of the wall of the tubular body and determining the magnitude of the annular gap.

 Considering the above and other purposes, in accordance with the invention, a combined syringe for sealing seams and a cartridge are provided. The cartridge has a mainly tubular body, a front injection nozzle on the front of the tubular body, a rear wall with the ability to move inside the tubular body, a tubular body that determines the size of the chamber located between the front and the rear wall. Thus, the syringe for sealing the seams consists of a body forming a flow for placing the cartridge, and a piston with the possibility of moving it parallel to the tray to push forward the rear wall inside the tubular body and reduce the volume of the chamber in the cartridge. The tubular body has a wall with an inner wall surface defining the inner diameter of the tubular body, and a back wall having a diameter smaller than the inner diameter of the tubular body, and defining a substantially free annular gap between the inner wall surface and the rear wall.

 In accordance with another feature of the invention, means are provided that act in conjunction with the tubular body of the cartridge to prevent the expansion of the tubular body while the piston moves the rear wall forward. These protective means can be presented in the form of a rigid tubular sleeve tightly mounted on the tubular body, for example, by inserting a cartridge into the sleeve.

 In accordance with another feature of the invention, the tubular sleeve is made of a solid material selected from the group comprising polyvinyl chloride, fiber and metal.

 In accordance with another feature of the invention, a safety device is provided in the form of a clamping device located at the syringe tray for sealing the seams for selectively securing the tubular body of the cartridge.

 In accordance with an accompanying feature of the invention, the syringe for sealing the seams has a control lever that moves the piston forward when the sealing composition is pumped, and the clamping device is connected to the control lever of the syringe for sealing the seams so that the tubular body is clamped simultaneously with the piston moving the rear wall forward.

 Other features that are considered characteristic of the invention are set forth in the appended claims.

 Despite the fact that the invention is illustrated and described here in relation to the implementation in the form of a syringe and cartridge for sealing seams to prevent leakage after injection, however, it is assumed that its use is not limited only to the examples shown, since, without departing from the spirit of the invention and the limits of capabilities and the boundaries of the equivalents of the formula, modifications and structural changes are possible.

 However, a better understanding of the invention for practical use, taking into account additional goals and advantages, will be achieved after reading the following description of a specific embodiment of the invention using the accompanying drawings.

 In FIG. 1 is a perspective view of a prior art syringe seal.

 In FIG. 2 shows a longitudinal section through a cartridge for sealing joints.

 In FIG. 3 shows a longitudinal section through a seam cartridge according to a first embodiment of the invention.

 In FIG. 4 shows a vertical section through the back wall of a cartridge for sealing seams of a second embodiment of the invention (rear view).

 In FIG. 5 shows a section along line V-V of FIG. 4.

 In FIG. 6 shows a vertical section through a piston according to the embodiment of FIG. 4 and 5 (front view).

 In FIG. 7 is a longitudinal section through a rigid sleeve according to a third embodiment of the invention.

 In FIG. 8 is a schematic illustration of a syringe tray for sealing seams (front view).

 In FIG. 9 shows a vertical projection of a syringe for sealing seams with a clamping device (side view).

 Turning now to the consideration of the drawings and, first of all, to FIG. 1, which depicts a conventional syringe for sealing joints. The front of the housing 1 has a tray 2 for accommodating the discharge cartridge. The piston rod 3 pushes the head of the plunger 4 forward in the direction of the wall 5 of the front of the tray 2. The locking latch 6 prevents the rod 3 from moving in the opposite direction, and the spring 7 holds the latch 6 in the locked position. When the latch 6 is turned forward almost to the vertical unlocking position, the rod 3 is released and begins to move in the opposite direction.

 In FIG. 2 shows a conventional prior art syringe sealing joint that has a tubular body 8. The body is typically formed in the form of a cylindrical tube 8 of paper laminate, fiberboard, sheets of rolled metal from materials like them. The cylindrical tube 8 is relatively soft, and with increasing pressure in its inner chamber, it expands in the radial direction. On the front wall of the closure 10 there is a nozzle tip 9. The tightness of the pipe 8 in the rear is provided by the rear wall 11. The outer cylindrical flange 12 of the rear wall 11 has an outer radius that corresponds to the inner radius of the pipe 8. The flange 12 forms a movable seal between the inner surface of the pipe wall 8 and the rear wall 11. A ring ring 14 with a cylindrical the seal flange 15 is clamped to the trailing edge of the pipe 8. During storage, the rear wall 11 is located adjacent to the ring 14 so that the flange 12 is in a clamped position under the seal flange 15. Only after the front wall 10 is pierced and the nozzle tip 9 is cut off to form an injection hole, the rear wall 11 begins to move forward to pump the sealing composition 13.

 As soon as the rear wall 11 is pushed forward and the flange 12 begins to slide along the inner surface of the pipe wall 8, the sealing composition 13 is squeezed out of the discharge tip due to the increased pressure created in the pipe chamber. Simultaneously with the extrusion of the composition 13 from the pressure tip, the increased pressure also causes the expansion of the volume of the pipe body in the radial direction. In fact, it can be shown that the radial pressure on the wall of the cylindrical pipe is exactly two times higher than the axial pressure acting in the direction of the discharge hole. Such radial "breathing" of the pipe 8 causes leakage when the piston 4 stops, and the pipe 8 gradually reduces its increased diameter to its original state.

 In FIG. 3 shows a first embodiment of the invention when the outer diameter (OD) of the cylindrical flange 12 is less than the inner diameter (ID) of the pipe 8 by the size of the annular gap Δ D. The annular gap Δ D is selected depending on the sealing composition 13, that is, on the viscosity and reaction rate with air. In other words, the higher the viscosity of the composition, the greater the magnitude of the annular gap Δ D. Further, the more inert the composition with respect to the atmosphere, the larger the magnitude of the Δ D. In general, for pipes of organosilicon polymers, glycerol esters and resin acids and the like, the annular gap may be Δ D = 1 mm.

 Tubes for higher viscosity formulations may have Δ D ≤ 0.2 mm. The proper size of the annular gap can be selected by an experienced specialist.

 The flange 12 and the inner surface of the wall of the pipe 8 create a free seal due to the small amount of sealing composition seeping between them. Due to the fact that the area of the injection hole is much larger than the area determined by (approximately) the size of the annular gap times the circumference, only a small amount of the sealing composition can be seeped along this route. As soon as the pressure on the piston weakens and the piston begins to move in the opposite direction, wall 11 follows it until the pipe wall assumes its normal position. Since the sealing composition located in the annular gap between the flange 12 and the pipe is still fresh (its viscosity is almost at its maximum), the rear wall 11 slides easily. Shortly after the back wall has returned to its normal position (that is, after the voltage drops across the pipe body), the remaining sealing composition hardens by the action of air and thus creates an appropriate seal. The remaining composition in the chamber of the cartridge is located in a sealed space and is not exposed to air.

 After manufacture, that is, during storage on a shelf prior to first use, the rear wall 11 is sealed like conventional known systems.

 A sealing pipe system with an annular gap Δ D> 0.0 mm may seem illogical at first glance, since the compositions contained in such pipes are cured by contact with air, and any application does not correspond to common sense. However, the inventor was able to verify that after this system has been actuated, a sealing ring of hardened composition is formed between the flange 12 and the inner surface of the pipe wall 8. As the piston 4 pushes the back wall 11 forward during the next pumping operation, this temporary seal breaks and a sliding seal is created between the flange 12 and the inner surface of the pipe wall 8. The rod 3 is pressed against the piston 4 immediately after the end of the injection, the compressive force of the pipe 8 is able to push the back wall 11 back and not contribute to the formation of unwanted leakage.

 In FIG. 4 presents a second embodiment of the invention, which can be used in the first embodiment of the invention and which is determined by the feature of forced delay. On the flange 12 there are two opposite latches 16. As soon as the piston 4 extends to the position defined by the flange 12, it engages with the latches 16. With this type of engagement of the rear wall 11, it is possible to force the rear wall 11 back by pulling it on the rod 3. In a preferred embodiment of the invention (Fig. 6), the piston plunger 4 may have cutouts 17 that allow selective engagement of the piston 4 with latches 16.

 In FIG. 4, it can also be seen that the annular gap between the inner surface of the pipe wall and the flange 12 can be defined by the protrusions 19 formed on the periphery of the wall 11, that is, on the flange 12.

 In a third embodiment of the invention, the pipe 8 is prevented from expanding in the radial direction by a rigid sleeve 18 worn on the pipe 8. The sleeve 18 may be made of polyvinyl chloride, fiberglass, metal or any similar material. The inner diameter of the sleeve 18 is selected so that it matches the outer diameter of the pipe 8. Moreover, the sleeve 18 is made so thin that it can be inserted into the tray 2 of the syringe to seal the seams.

 In FIG. 8 shows that the rigid sleeve can be replaced by a top cover 20, which is pivotally mounted on the side of the tray 1 of the syringe body to seal the seams. Since the cap 20 is closed and secured with a hook 21, a rigid sleeve is formed for the pipe with the sealing composition.

 And finally, in the fourth embodiment of the invention, the pipe 8 is further crimped for the pumping operation by advancing the rear wall 11. The pressure from the pipe 8 is removed after the pumping is completed. In a preferred embodiment of the invention, a clamping device is also provided on the syringe for sealing the seams, which compresses the pipe while pushing the rear wall 11 forward. In FIG. Figures 8 and 9 show that the lid 20 is fastened with two films 22 connected on one side to the latch 21 and on the other hand to the housing 1 of the tray. When the control lever 23 is set to the position of the piston 4 in motion, the wedges 24 extend below the plates 22. As a result, the plates tighten the lid 20 more tightly and thereby forcefully clamp the sealing pipe 8. It is preferable that the lid 20 has a slightly larger diameter than the diameter of the tray . Due to this, the space in which the cartridge with the sealing composition is placed has a slightly oval cross section.

 The terms "syringes for sealing joints" and "sealing compounds" used in this material should be understood as terms generally accepted in the known field of technology, namely: any dispensing and metering devices with a piston that reduces the volume in tubular containers, and compositions of any type requiring solutions to the aforementioned leakage problems.

Claims (10)

 1. A cartridge for sealing joints, relating to a type having mainly a tubular body, a front pressure hole on the front of the tubular body, a rear wall with the ability to move inside the tubular body, a tubular body having a wall with an inner surface of the wall defining the inner diameter of the tubular body and a tubular body defining there a chamber bounded by an inner surface of the wall, a front part and a back wall, characterized in that the back wall has a smaller diameter than the inner diameter emp tubular body and defines a substantially annular free space between the inner wall surface and the contour of the rear wall.  2. The cartridge according to claim 1, characterized in that the aforementioned annular gap is at least 0.2 mm  3. The cartridge according to claim 1, characterized in that the aforementioned annular gap is at least 1.0 mm  4. The cartridge according to claim 1, characterized in that it further has spacer protrusions formed on the periphery of the dented rear wall, the spacer protrusions in contact with the inner wall surface of said tubular body and define said annular gap.  5. The combination of a syringe for sealing the seams and the cartridge, containing said cartridge having a basically tubular body, a front injection nozzle in the front of said tubular body, a rear wall that can be moved inside said tubular body, said tubular body defining a chamber between said front a part and a back wall, said syringe for sealing seams, including a housing forming a flow for accommodating said cartridge, and a piston with the possibility of movement in parallel said tray for pushing said rear wall forward inside said tubular body and reducing the volume inside said chamber in said cartridge, said tubular body having a wall with an inner surface defining an inner diameter of said tubular body, characterized in that said back wall has a smaller diameter than the inner diameter of the tubular body, and which defines a substantially free annular gap between the inner surface of the wall and the rear wall.  6. The combination of the syringe for sealing the seams with the cartridge, relating to the type in which the cartridge has a mainly tubular body, a front discharge hole on the front of the tubular body, a rear wall with the possibility of movement inside the tubular body and the syringe for sealing the seams has a tray for accommodating the cartridge and a piston with the ability to move parallel to the tray to push the back wall inside the tubular body and to reduce the volume inside the tubular body and reduce the volume inside the cartridge chamber, characterized in that it includes means acting in conjunction with the tubular body of the cartridge to prevent radial expansion of the tubular body when the piston extends the rear wall forward, and the rear wall of the tubular body has a diameter smaller than the inner diameter of the tubular body, and defines a substantially free annular the gap between the inner surface of the wall and the rear wall.  7. The combination according to claim 6, characterized in that the said protective means are determined by a rigid tubular sleeve tightly mounted on the tubular body.  8. The combination according to claim 7, characterized in that the said tubular sleeve is made of a solid material selected from the group comprising polyvinyl chloride, fiber and metal.  9. The combination according to claim 6, characterized in that the safety device is presented in the form of a clamping device located at the syringe tray for sealing the seams to selectively secure the tubular body of the cartridge.  10. The combination according to claim 9, characterized in that the syringe for sealing the seams has a control lever that moves the piston forward when the sealing composition is pumped, and said clamping device is connected to the control lever of the syringe for sealing the seams so that the tubular body is clamped simultaneously with the beginning the piston extends the rear wall forward.

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