MXPA96005146A - Improvements in impulsor arms sets for cleaning sheets - Google Patents

Abstract

A pivot connection between a driving head and a driving arm of a wiper drive arm assembly, said pivot connection comprising laterally disposed driving arm side wall portions arranged to be pivotally connected to said driving head and retaining means acting between said driving arm and said driving head to limit relative pivotal movement between said driving arm and said driving head, whereby a proximal edge of an upper wall of the lateral driving arm, extending between the wall portions laterally of the driving arm, arranged laterally, do not come into contact with a central area of an upper wall of the driving head in a closed rear position of the driving arm

Description

IMPROVEMENTS IN DRIVER BOOMS FOR CLEANER SHEETS The present invention relates to improvements in drive arm assemblies for wiper blades. Conventionally, the wiper blade drive arm assemblies comprise a drive head adapted to be secured to a drive system that includes a drive motor for oscillatory movement. The drive arm assembly typically includes a drive arm member pivoted to the drive head with the wiper blade mount pivoted to an outer end of the drive arm member. A spring arrangement is located between the driving head and the driving arm member in such a way as to provide a downward force on the cleaner support frame such that it urges the cleaning blade towards the windshield when in use. The spring arrangement is also configured to allow the driving arm member to be pivoted away from the windshield to be retained in a closed rear position, the spring arrangement being in a position above the center so that the windshield can be cleaned, or maybe the cleaning sheets can be changed. Commonly, the connection of the pivot of the drive arm member to the driving head is formed by providing a pair of flanges extending from the side walls of the driving arm member thereafter to be located away from the adjacent side walls of the driving head. , a pivot pin being located through the pair of flanges of the driving arm member and the side walls of the driving head A retainer is provided to prevent movement of the driving arm member beyond a predetermined closed rear position, by a upper wall edge of the driving arm member extending between the pair of pivotal mounting tabs being arranged to engage an upper wall of the driving head While the arrangements of this general type to work satisfactorily, unfortunately, they also have a practical disadvantage in that when the arm member impeller moves towards the closed rear position, it is possible to damage or crack the paint on the driving head by the aforementioned coupling of the upper rear edge on the upper surface of the driving head This can provide an unpleasant appearance, but can also promote premature corrosion and possible failure of the driving head. Therefore, the object of the present invention is to provide an improved drive arm assembly for a cleaning blade that substantially overcomes the difficulties previously treated with existing or conventional drive arm assemblies. present invention provides a pivot connection between a drive head and a drive arm of a wiper drive arm assembly, said pivot connection comprising side wall portions of the drive arm disposed laterally, arranged to be pivotally connected to said drive head and means d and act by acting between said driving arm and said driving head, whereby a proximal edge of an upper wall of said driving arm, extends between said side portions of the laterally disposed driving arm wall, does not come into contact with a driving arm. central area of an upper wall of the driving head in a closed rear position of the driving arm Preferably, at least one or both of laterally disposed driving arm side wall portions are arranged to be received within depressed zones in the regions of side wall of the drive head with the pin (or pivot pins) extending through laterally disposed side wall portions Conveniently, the retaining means comprise first forming means on said driving head adapted to be coupled with second forming means located on said driving arm with said second forming means engaging in the closed posterior position, said first and second forming means being arranged in or adjacent to one or both side regions of the pivot connection. Preferably, the first forming means comprises a portion of an edge of each depressed zone in the side regions of the drive head. Preferably, the second forming means comprise a portion of an edge of laterally disposed driving arm sidewall portions. By the arrangements of the type mentioned above, the required functional performance of the wiper drive assembly is achieved, but the damage and visible unpleasant appearance of the top of the drive head is prevented. A preferred embodiment will be described below with reference to the accompanying drawings in which: Figures 1A and 1B are respectively a side sectional view and a plan view of a cleaner drive assembly according to the prior art.; Figure 2 is a top plan view of a cleaner drive assembly according to the present invention; Figure 3 is a detailed plan view of the pivotal area marked B in Figure 2; Figure 4 is a side elevational view of the cleaner drive assembly shown in Figure 2; Figure 5 is a detailed side view of the area of the pivot marked A in Figure 4; Figure 6 is a side elevational view similar to the Figure 4, showing the wiper driving arm in a closed rear position; and Figure 7 is a detailed view of the pivot area marked A in Figure 6.

Referring first to Figures 1A and 1B, a conventional cleaner drive arm assembly 10 is illustrated comprising a drive head 11 adapted at 12 to be connected to the drive system (not shown). A drive arm 13 is shown having a pair of backwardly extending tabs 14, 15, extending from the side walls 16, 17 of the drive arm 13 such that the tabs are located outwardly from the side walls 18, 19 of the drive head 11 A pivot pin 20 connects the flanges 14, 15, to the side walls 18, 19 of the drive head with a spring assembly 21 acting between the head 11 and the drive arm 13 to provide both a force pushing the end free (not shown) of the arm 13 towards a windshield (in use) or alternatively, as providing a rear holding or closing force when the arm 13 is pivoted in the direction opposite to the m clock anecdotes (Figure 1A) around the pin of the pivot 20 The closed rear position occurs when the trailing edge 22 of the upper surface 23 of the driving arm 13 engages with the surface 24 of the driving head 11 in the region identified by the number 25 As discussed above, this contact is what causes both an unpleasant appearance and damage to the driving head. Referring now to Figures 2 to 7, we can observe first that the function and components of the described set, generally as discussed above with reference to Figures 1A and 1B except the specific issues discussed below. In these embodiments, in accordance with this preferred aspect of the present invention, the pivot connection 26 between the driving head 11 and the driving arm 13, are created by forming depression zones 27 in the side walls 18, 19 of the head of the head. drive 11. Through this arrangement, it is possible to arrange the width of the head 11 to be substantially the same as for the arm 13, thus providing improved appearance for the assembly 10 as a whole. The depressed zones 27 conveniently include a retention passage portion 28 on a bank 29 of the zone. Conveniently, the portion 28 of the retaining step is located adjacent the top of the edge 29 such that the upper wall 24 of the driving head is located substantially at the corner between the side walls 18, 19. The portion 28 of the detent step is conveniently arranged to engage with a portion of the detent step 30 on the edge 31 of the flanges 14, 14, in the drive arm 13, such that the portions of the step 28 and 30, form together a limit retention to prevent the arm 13 of Figure 5 from being pivoted about the pivot pin 20, in the clockwise direction beyond a rear limit or closed position, as shown in Figures 6 and 7. In the closed rear position, the trailing edge 22 of the upper wall 23, of the driving arm 13, is kept out of contact with the upper wall 24 of the driving head. Of course, it is preferred to provide on both sides of the assembly, a limit stop of the type described above, but of course, the provision of same on one side may also be functional. In this way, an improved appearance for a drive assembly is achieved. cleaners, and in addition, unpleasant damage to the driving head is avoided.

Claims (1)

1. CLAIMS 1 A pivot connection between a drive head and a drive arm of a wiper drive arm assembly, said pivot connection comprising laterally disposed lateral drive arm wall portions arranged to be pivotally connected to said drive head and drive means. retention acting between said driving arm and said driving head to limit relative pivotal movement between said driving arm and said driving head, whereby a proximal edge of an upper wall of the lateral driving arm, extending between the portions side wall of the driving arm, arranged laterally, do not come into contact with a central area of an upper wall of the driving head in a closed rear position of the driving arm 2 A pivot connection according to claim 1, wherein at least one of said portions of side wall of drive arm disposed beats It is arranged to be received in a depressed area in a side wall region of the drive head 3 A pivot connection according to claim 2, in which both sides of the laterally disposed driving arm side wall are arranged in said respective depressed zone in the side regions of driving head 4 A pivot connection according to claim 2 or claim 3, wherein said retaining means comprise first training means located on said driving head adapted to engage with the second forming means located on said driving arm in said rear position of the arm, said first and second forming means being arranged in or adjacent to one or both lateral regions of the pivot connection. A pivot connection according to claim 4, wherein the first forming means comprises an edge of each depressed zone in the side regions of the drive head. A pivot connection according to claim 4 or claim 5, wherein the second forming means comprises a portion of an edge of at least one of the lateral wall portions of the drive arm arranged laterally . 7. A set of wiper blades comprising a drive head, drive arm, wiper blade arrangement connected to said drive arm and a pivot connection according to any of claims 1 to 6, disposed between said head of drive and said drive arm.