WO2025217670A1

WO2025217670A1 - Vacuum dent pulling tower

Info

Publication number: WO2025217670A1
Application number: PCT/AU2025/050351
Authority: WO
Inventors: Clem Cuschieri
Original assignee: Individual
Current assignee: Individual
Priority date: 2024-04-18
Filing date: 2025-04-11
Publication date: 2025-10-23
Anticipated expiration: 2026-10-18

Abstract

A vacuum dent pulling tower comprises a base with a peripheral seal assembly surrounding a central vacuum space. Outer and inner rails define a channel retaining a compliant seal and at one or more protective friction pads. The friction pads shield the seal from abrasion when the base is dragged across a floor, while the metallic rails prevent inward collapse under suction, allowing the system to maintain high vacuum forces. The seal may protrude slightly to ensure vacuum engagement but remains protected between harder friction pads, which are preferably removable and U-shaped for ease of maintenance. A carriage assembly may be integrated within the vacuum space to lift the base when vacuum is released, enabling lateral movement on wheels. This arrangement enhances durability, vacuum performance, and serviceability, addressing the limitations of conventional adhesive sponge pads prone to damage and difficult to replace.

Description

Vacuum Dent Pulling Tower

Field of the Invention

[0001 ] The present invention relates to the field of automotive repair equipment, and in particular to vacuum-based dent pulling towers used to remove dents from vehicle panels. The invention concerns an improved vacuum anchoring system having a peripheral seal assembly protected by friction pads and optionally incorporating a retractable carriage system.

Background of the Invention

[0002] A vacuum dent pulling tower is an advanced tool used in the automotive repair industry for removing dents from vehicle panels. It consists of a base equipped with a vacuum system that secures it to the floor, a tower supporting a winch unit, and a winch line with adapters or pulling tabs for engaging and pulling dents out of vehicle surfaces. The vacuum system creates a strong seal against the floor, enabling the tower to exert the necessary force without shifting its position. To enhance this system's functionality, a compression pad, often made from closed-cell rubber sponge, is applied to the undersurface of the baseplate. This pad induces a vacuum and increases frictional contact with the floor, providing additional resistance against shear forces that occur during the dent pulling process.

[0003] However, while the closed-cell rubber sponge is effective in enhancing the vacuum dent pulling tower's grip on the floor, its soft and non-durable nature makes it susceptible to wear and damage. This is particularly true under the intense shear forces applied during use and when the base is dragged across the floor. Replacing these rubber sponges presents a challenge; they are typically affixed to the baseplate with an adhesive backing, which must be painstakingly scraped off and cleaned before a new pad can be installed. This process can be time-consuming and laborious, detracting from the overall efficiency of maintenance and repair operations involving the vacuum dent pulling tower. [0004] It is to be understood that, if any prior art information is referred to herein, such reference does not constitute an admission that the information forms part of the common general knowledge in the art, in Australia or any other country.

Summary of the Disclosure

[0005] The described vacuum dent pulling tower comprises a base supporting a tower, wherein the base includes a peripheral seal assembly surrounding a central vacuum space within which a vacuum is induced in use. The peripheral seal assembly comprises outer and inner rails that define a channel, with a seal installed within the channel to provide vacuum sealing capability. At least one friction pad covers an exposed edge of a respective rail, to protect the more compliant seal from abrasion. [0006] This arrangement addresses the durability and maintenance issues associated with conventional sponge pads by locating the seal in a protected, recessed position with respect to at least one abrasion-resistant friction pad.

[0007] The friction pads, which are preferably harder than the seal, withstand shear and scraping forces when the base is moved or dragged across the floor, thereby prolonging the life of the sealing element. The rail, which is preferably metallic, reinforces the structure and resist inward collapse of its respective friction pad under vacuum pressure. This enables the tower to maintain high vacuum adhesion — such as in excess of 90 kPa — while reducing the risk of seal damage. Moreover, the seal is able to operate between the rails to conform to the floor surface during vacuum engagement, allowing a peripheral sealing configuration to be used without requiring full coverage beneath the base. This simplifies construction, improves vacuum efficiency, and reduces the area of wear-prone material. The arrangement also facilitates easier maintenance, as the friction pads may be removably attached to the rails without adhesives, avoiding the labour-intensive scraping procedures required for replacement in prior art systems.

[0008] Preferably, outer and inner friction pads are provided to cover the outer and inner rails respectively, further enhancing protection of the seal and resistance to shear forces. The seal is preferably more compliant than the friction pads, enabling it to conform to floor irregularities while the pads absorb abrasive contact. The seal may comprise a foam-like material, preferably a closed-cell foam such as ethylenevinyl acetate (EVA), which provides vacuum sealing performance and resilience under repeated compression.

[0009] The friction pads may comprise a harder material such as rubber, optionally having a hardness exceeding Shore A 70, thereby offering enhanced durability against wear from movement across floor surfaces. The outer and inner rails are preferably metal flanges extending perpendicularly from a base plate and may be welded thereto, ensuring structural rigidity. In preferred embodiments, the seal is adhered directly to the base plate to maximise sealing integrity.

[0010] In some embodiments, the seal may protrude slightly beyond the friction pads to initiate vacuum sealing contact with the floor surface. The friction pads are preferably U-shaped and removably fitted over the rails, optionally by hand, to simplify replacement and maintenance. Each friction pad may include sides and a web forming a channel that fits around the respective rail, with the web having a flat exterior surface to assist sealing, and the sides having flat inner surfaces and flat edges that abut the base plate to minimise leakage paths.

[0011 ] In a further preferred form, the tower includes a carriage assembly interfacing the base and configured to assume a raised position wherein the base is lifted away from the floor surface when no vacuum is applied, and a lowered position wherein the peripheral seal assembly contacts the floor surface during use. The carriage assembly may be installed within the vacuum space, thereby maximising the usable sealing area.

[0012] Preferably, a pair of carriage assemblies are provided at opposite ends of the vacuum space, enabling lateral movement of the base when not secured. Each carriage assembly may comprise an elongate chassis, such as a rectangular hollow section (RHS) bar, retaining bearings that may be wheels for unidirectional repositioning or alternatively spherical or castor bearings for multidirectional manoeuvring. A jack may connect the chassis to the base plate and be biased by compression springs to lift the base when the vacuum is not applied. One or more stopper posts may be included to define the jack's maximum extension in the raised position.

[0013] These features combine to provide a robust, reliable, and maintainable vacuum anchoring system for dent pulling operations that improves sealing effectiveness, reduces wear on key components, and simplifies replacement and repositioning between uses.

[0014] Other aspects of the invention are also disclosed.

Brief Description of the Drawings

[0015] Notwithstanding any other forms which may fall within the scope of the present invention, preferred embodiments of the disclosure will now be described, by way of example only, with reference to the accompanying drawings in which:

[0016] Figure 1 shows a perspective view of a vacuum dent pulling tower in use.

[0017] Figure 2 shows an underside view of the base, including a peripheral seal assembly.

[0018] Figure 3 shows a lateral cross-sectional view of the base.

[0019] Figure 4 shows a detailed cross-sectional view of the peripheral seal assembly. [0020] Figure 5 shows the underside of the base with an integrated carriage assembly.

[0021 ] Figure 6 shows a side view of the carriage assembly in the raised position.

[0022] Figure 7 shows an end of the carriage assembly in the lowered position.

Description of Embodiments

[0023] Figure 1 shows a vacuum dent pulling tower 100 comprising a base 102 supporting a post 103. The post 103 may support a winch unit 104, which retracts a winch line 105 having adapters or pulling tabs 106 at a distal end thereof. In use, the tower 100 is placed on a floor surface adjacent a vehicle to be repaired, and a suction force is induced under the base 102 (typically by a Venturi using a commonly available compressed air system) to secure it to the floor surface and thereby resiliently support the post 103 against lateral traction forces applied by the winch unit 104. [0024] Figure 2 shows an underside of the base 102 comprising a peripheral seal assembly 107 surrounding a central vacuum space 108. In the embodiment shown, the base 102 is generally rectangular, and the peripheral seal assembly 107 closely follows the edges of the base 102, thereby maximising the size of the central vacuum space 108 and thus the suction adhesion to the floor surface in use. In this regard, the peripheral seal assembly 107 may comprise straight sections running along respective edges of the base 102 and rounded corners transitioning around the corners of the base 102. The vacuum space 108 is preferably devoid of any other objects, such as rubber friction pads or the like, allowing for an increased cross- sectional area and enhanced vacuum efficiency.

[0025] Figure 3 shows a lateral cross-sectional view of the base 102, and Figure 4 shows a more detailed cross-sectional view of the peripheral seal assembly 107.

[0026] With reference to Figure 4, the peripheral seal assembly 107 comprises an outer rail 109A and an inner rail 109B defining a channel 1 14 therebetween. A seal 110 is installed within the channel 1 14 around the central vacuum space 108. Furthermore, at least one friction pad 1 11 covers an exposed edge 112 of a respective rail 109. In the embodiment shown, the base 102 may comprise a baseplate 1 13, typically metallic such as aluminium, and the rails 109 may be planar and extend perpendicularly from the baseplate 113. With reference to Figure 2, these rails 109 may run generally parallel with respect to each other around the periphery of the base 102, thereby defining the peripheral channel 114 surrounding the vacuum space 108. [0027] According to the preferred embodiment shown in Figure 4, an outer friction pad 11 1 A covers the exposed edge 1 12 of the outer rail 109A, and a separate inner friction pad 1 1 1 B covers the exposed edge 1 12 of the inner rail 109B.

[0028] Preferably, the seal 110 is more compliant than the friction pads 11 1 and may comprise a sponge or foam-like material, especially a closed-cell foam-like material such as ethylene-vinyl acetate (EVA) foam. The friction pads 111 may comprise a less compliant or harder material, such as rubber. Preferably, the rubber has a hardness exceeding Shore A 70. Further preferably, the rails 109 are metal and may be welded directly onto the baseplate 1 13. [0029] The friction pads 1 1 1 protect the more fragile seal 1 10. When the base 102 is dragged across the floor surface, the more resilient friction pads 1 1 1 withstand abrasion whilst protecting the more compliant seal 110 located between them. The rails 109, preferably metallic, resiliently prevent the friction pads 1 11 from collapsing under suction force, thereby allowing the base 102 to withstand substantial vacuum force, such as in excess of 90 kPa.

[0030] However, when a vacuum is induced within the vacuum space 108, the more compliant seal 110 is able to operate between the friction pads 1 11 to conform to the floor surface and seal the vacuum space 108. According to this arrangement, the seal

I I 0 need not cover the entirety of the vacuum space 108 as in prior art arrangements, and its peripheral configuration is sufficient to effectively seal around the vacuum space 108.

[0031 ] Figure 4 shows that the seal 1 10 may extend slightly beyond the friction pads

I I I to ensure that it makes initial floor contact to commence vacuum induction, although it can be compressed in between the protective friction pads 11 1 when pressed against the floor surface without sustaining substantial damage or abrasion. [0032] According to the preferred embodiment shown in Figure 4, the friction pad 1 11 may be substantially U-shaped, defining sides 115 with an intervening web 116 that forms an interior channel therebetween to receive the rail 109. This configuration allows the friction pads 11 1 to be easily removed from the rails 109 by hand for replacement, requiring no specialised tools for maintenance.

[0033] The friction pad 11 1 is preferably continuous round the entire periphery of the vacuum space 108 and its web 116 preferably defines a flat exterior surface 1 17 so that it can press flat against the floor surface, enhancing the vacuum seal. Furthermore, the sides 115 preferably define flat inner surfaces which press flat against respective planar sides of the rail 109, thereby preventing air leakage between the rail 109 and the friction pad 1 11.

[0034] Further preferably, the sides 115 contact the baseplate 1 13, thereby enhancing the vacuum seal and preventing air loss between the sides 1 15 and the baseplate 113. The sides 115 themselves may define flat edges 1 18 that interface flat against the baseplate 1 13, further enhancing the seal between the sides 1 15 and the baseplate 1 13.

[0035] These friction pad shapes and geometries enhance the seal formed by the seal assembly 107.

[0036] Figures 6 to 7 illustrate an embodiment wherein the tower 100 comprises a carriage assembly 119, which is configured to lift the base 102 from the floor surface when no vacuum is applied, enabling the tower 100 to be wheeled. Specifically, the carriage assembly 119 interfaces with the base 102 and is configured to assume a raised position wherein the carriage assembly lifts the base 102 away from the floor surface when no vacuum is induced in the central vacuum space 108, and a lowered position wherein the carriage assembly lowers the peripheral seal assembly 107 to the floor surface.

[0037] In the embodiment of Figure 5 showing the underside of the base 102, the carriage assembly 119 is installed within the vacuum space 108, thereby maximising the size of the vacuum space 108 within the confines of the base 102.

[0038] Furthermore, the embodiment of Figure 5 illustrates a pair of carriage assemblies 1 19 installed at respective ends of the vacuum space 108, configured for lateral movement of the base 102. Each carriage assembly 119 may comprise a chassis 120, which may be elongate and narrow, such as being an RHS bar. The chassis 120 retains bearings 121 , preferably a quadrant of bearings 121 on both sides and ends of the chassis 120. In the embodiment shown, these bearings 121 are wheels for unidirectional repositioning of the tower 100, although they could alternatively comprise spherical bearings or castor wheels for multidirectional manoeuvring.

[0039] A jack 122 may interface the chassis 120 between raised and lowered positions. In the embodiment shown, compression springs 123 bias the jack 122 away from the chassis 120, and stopper posts 124 may limit the position of the jack 122 in the raised position. The jack 122 may comprise a plate which attaches to the undersurface of the baseplate 1 13 and which may abut the chassis 120 when in the lowered position. [0040] As such, when no vacuum is induced within the vacuum space 108, the compression springs 123 bias the jack 122 away from the chassis 120, overcoming the weight of the base 102 and post 103, thereby allowing the tower 100 to be wheeled on the bearings 121. However, when a vacuum is induced within the vacuum space 108, the suction force overcomes the resilience of the compression springs 123, allowing the seal assembly 107 to contact the floor surface.

[0041 ] In an example method of use, the vacuum dent pulling tower 100 is transported to a desired location adjacent a vehicle panel requiring dent removal. With reference to Figure 1 , the operator positions the base 102 flat on the floor surface, typically a concrete or similarly hard and flat substrate, such that the post 103 is oriented upright and generally perpendicular to the floor surface.

[0042] Initially, the carriage assemblies 119, described in Figures 5 to 7, are in the raised position, whereby the compression springs 123 urge the chassis 120 downward relative to the jacks 122, causing the bearings 121 to support the weight of the base 102 and elevate the peripheral seal assembly 107 from the floor. In this configuration, the tower 100 may be wheeled laterally to fine-tune its position with respect to the vehicle.

[0043] Once correctly positioned, a compressed air line is connected to the Venturi device associated with the base 102. The operator then activates the Venturi, which induces a negative pressure within the central vacuum space 108. As suction develops, the vacuum force acts through the vacuum space 108, drawing the peripheral seal assembly 107 — including the seal 110 and the friction pads 1 1 1 — into sealing engagement with the floor surface. The suction force is sufficient to overcome the upward bias of the compression springs 123, thereby retracting the jacks 122 into the chassis 120 and allowing the full underside of the baseplate 1 13 and the seal assembly 107 to come into direct contact with the floor surface. In this state, the base 102 is firmly secured to the floor and capable of resisting substantial lateral forces.

[0044] The compliant seal 110, as described in Figure 4, deforms to accommodate any minor irregularities in the floor surface, thereby ensuring an airtight seal around the vacuum space 108. The friction pads 11 1 on the outer rail 109A and inner rail 109B, being harder than the seal 1 10, bear the brunt of any abrasive contact during positioning or accidental movement and protect the more delicate seal 110 from damage.

[0045] With the base 102 now firmly anchored to the floor, the operator engages the winch unit 104 mounted to the post 103. The winch line 105 is extended and attached to a pulling tab or adapter 106, which is previously bonded or attached to the dented portion of the vehicle panel. Once secured, the operator activates the winch unit 104 to retract the winch line 105, thereby applying a pulling force to the dent.

[0046] The lateral traction force generated during this process is transmitted through the post 103 to the base 102. The rigid structure of the baseplate 1 13, combined with the firm vacuum seal established by the seal assembly 107, ensures that the tower 100 remains in a fixed position during operation. The friction pads 1 11 also provide lateral resistance against shifting or sliding, particularly during high-force pulls.

[0047] Upon completion of the dent repair process, the vacuum is released by deactivating the Venturi system. As the negative pressure dissipates, the seal 110 and friction pads 1 11 disengage from the floor surface. The compression springs 123 once again act to extend the jacks 122 upwards, raising the base 102 and enabling the operator to wheel the tower 100 away for repositioning or storage.

[0048] The foregoing description, for purposes of explanation, used specific nomenclature to provide a thorough understanding of the invention. However, it will be apparent to one skilled in the art that specific details are not required in order to practise the invention. For example, whereas the preferred embodiment shown in Figure 4 comprises a pair of rails 109 and a pair of respective friction pads 11 1 , in alternative embodiments, the tower 100 may comprise a pair of rails 109 with only one friction pad 1 1 1 installed on one of these rails 109. Furthermore, in some embodiments, the seal assembly 107 may comprise only a single rail 109 with a respective single friction pad 11 1 located on its inside or outside edge. Even in such configurations, the friction pad 11 1 provides abrasion resistance fo r the more fragile seal 1 10, thereby preserving sealing integrity and protecting against wear during dragging or repositioning of the base. Such arrangements may reduce manufacturing complexity or material costs while still delivering improved durability and vacuum performance over prior art designs. Thus, the foregoing descriptions of specific embodiments of the invention are presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms disclosed as obviously many modifications and variations are possible in view of the above teachings. The embodiments were chosen and described in order to best explain the principles of the invention and its practical applications, thereby enabling others skilled in the art to best utilize the invention and various embodiments with various modifications as are suited to the particular use contemplated. It is intended that the following claims and their equivalents define the scope of the invention.

Claims

1 . A vacuum dent pulling tower comprising: a base supporting a tower; wherein the base comprises a peripheral seal assembly surrounding a central vacuum space within which a vacuum is induced in use; wherein the peripheral seal assembly comprises outer and inner rails defining a channel therebetween, the channel surrounding the central vacuum space; wherein a seal is installed within the channel around the central vacuum space; and wherein at least one friction pad covers an exposed edge of a respective rail.

2. The vacuum dent pulling tower of claim 1 , wherein outer and inner friction pads cover the outer and inner rails respectively.

3. The vacuum dent pulling tower of claim 2, wherein the seal is more compliant than the friction pads.

4. The vacuum dent pulling tower of claim 3, wherein the seal comprises a foam-like material.

5. The vacuum dent pulling tower of claim 4, wherein the foam-like material is a closed-cell foam-like material.

6. The vacuum dent pulling tower of claim 5, wherein the closed-cell foam-like material comprises ethylene-vinyl acetate (EVA).

7. The vacuum dent pulling tower of claim 3, wherein the friction pad comprises rubber.

8. The vacuum dent pulling tower of claim 7, wherein the rubber has a hardness exceeding Shore A 70.

9. The vacuum dent pulling tower of claim 1 , wherein the outer and inner rails are metal.

10. The vacuum dent pulling tower of claim 9, wherein the base comprises a base plate from which the rails extend perpendicularly and wherein a backing surface of the seal is adhered directly to the base plate.

11 . The vacuum dent pulling tower of claim 1 , wherein the seal extends beyond the friction pad.

12. The vacuum dent pulling tower of claim 1 , wherein the friction pad is U-shaped.

13. The vacuum dent pulling tower of claim 12, wherein the friction pad is configured to be removed from its respective rail by hand.

14. The vacuum dent pulling tower of claim 12, wherein the friction pad comprises sides and a web defining a channel therebetween which fits a respective rail therein.

15. The vacuum dent pulling tower of claim 14, wherein the web defines a flat exterior surface.

16. The vacuum dent pulling tower of claim 14, wherein the sides define flat inner surfaces.

17. The vacuum dent pulling tower of claim 16, wherein the sides contact the base plate.

18. The vacuum dent pulling tower of claim 17, wherein the sides define flat edges interfacing the base plate.

19. The vacuum dent pulling tower of claim 1 , further comprising a carriage assembly interfacing the base and configured to assume: a raised position in which the carriage assembly lifts the base away from a floor surface when no vacuum is induced in the central vacuum space; and a lowered position in which the carriage assembly lowers the peripheral seal assembly to the floor surface.

20. The vacuum dent pulling tower of claim 19, wherein the carriage assembly is installed within the central vacuum space.

21 . The vacuum dent pulling tower of claim 20, comprising a pair of carriage assemblies installed at opposite ends of the central vacuum space and configured to permit lateral movement of the base.

22. The vacuum dent pulling tower of claim 21 , wherein each carriage assembly comprises a chassis retaining a plurality of bearings.

23. The vacuum dent pulling tower of claim 22, wherein the bearings comprise wheels for unidirectional repositioning of the base.

24. The vacuum dent pulling tower of claim 22, wherein each carriage assembly further comprises a jack attached to the base plate and biased away from the chassis by one or more compression springs.

25. A method of operating the vacuum dent pulling tower of claim 1 , the method comprising: positioning the base on a floor surface; inducing a vacuum within the central vacuum space to draw the peripheral seal assembly into sealing engagement with the floor surface; securing the base to the floor surface via the induced vacuum; applying a pulling force to a vehicle panel using a winch unit supported by the base; and releasing the vacuum to disengage the peripheral seal assembly from the floor surface.

26. The method of claim 25, wherein the vacuum dent pulling tower comprises a carriage assembly, and wherein: prior to inducing the vacuum, the carriage assembly is in a raised position such that the base is supported by one or more bearings; inducing the vacuum overcomes a biasing force of the carriage assembly and lowers the base into contact with the floor surface; and releasing the vacuum allows the carriage assembly to return to the raised position, enabling repositioning of the tower.