GB2088706A

GB2088706A - Wiper arms

Info

Publication number: GB2088706A
Application number: GB8037674A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1980-11-25
Filing date: 1980-11-25
Publication date: 1982-06-16
Also published as: GB2088706B

Abstract

A wiper arm assembly having a main arm 1 and a slave arm 3 pivotally connected at their free ends 7, 13 to a connection member 9 which supports a wiper blade 11 is characterised in that each arm is telescopically adjustable to a plurality of predetermined lengths. <IMAGE>

Description

SPECIFICATION Improvements relating to wiper arms The present invention relates to a wiper arm for use on a motor vehicle windscreen.

In particular the present invention relates to a wiper arm for use on a bus or wagon, the wiper arm being of the type comprising a main arm and a slave arm whereby a wiper blade secured to the main arm will remain substantially vertical as the wiper arm follows its usual arcuate path, the main arm and slave arm remaining substantially parallel to each other.

Wiper arms used on buses and wagons quite often become damaged due, for example, to their relatively heavy usage. Thus bus companies and the owners of wagon fleets have to maintain a stock of wiper arms for replacement purposes. This involves the tying up of capital funds, which funds could advantageously be utilised in other areas. As will be appreciated the above mentioned type of wiper arm is particularly expensive in view of the double arm arrangement, and to make matters worse, there are no fewer than six different dimensional variations, requiring usually, all of the variants to be retained in stock ready for immediate use. The dimensional variations occur in the length of the main and slave arms and their spacing from each other.

To add further to the expense, partly damaged wiper arms have to be completely replaced as they are provided as an integral unit.

The aim of the present invention is to provide a wiper arm of the above type which is adaptable to at least some of the dimensional variants.

According to the present invention there is provided a wiper arm for use on a motor vehicle, comprising a main arm and a slave arm pivotally inter-connected, said arms being telescopic and securable at a number of predetermined lengths.

Thus the present invention provides a wiper arm which can be selectively adjusted in length to fit the requirements of a particular vehicle. Clearly, as only one form of wiper arm need be retained in stock, the amount of stock retained, can be reduced, thus releasing capital funds. Preferably the main arm and the slave arm are connected to opposite end regions of a connection member, one or both of the slave and main arms being detachably connected to the connection member and adjustable in position thereon to provide for different spacings of main and slave arms from each other.

The main and slave arms will preferably be connected to drive and freely movable pivots respectively, by splined connections and to facilitate removal therefrom the main and slave arms may be provided with lugs which enable a tool to be engaged therewith.

The present invention will now be further described, by way of example, with reference to the accompanying drawings, in which: Figure 1 shows a preferred embodiment of the present invention installed on a vehicle; and Figure 2 is a rear view of the wiper arm shown in Fig. 1, when extended.

The wiper arm shown in the accompanying drawings comprises a main arm 1 and a slave arm 3. In Fig. 1, one end 5 of main arm 1, is connected to a motor drive (not shown) and the other end 7 is pivotally connected to connection member 9. A wiper blade 11 is detachably secured to connection member 9 and one end 13 of slave arm 3, is detachably and pivotally secured to connection member 9. Slave arm 3 extends parallel to main arm 1 and is secured to a pivot on the vehicle adjacent to said one end 5 of main arm 1.

Thus as the main arm 1 pivots back and forth so the slave arm maintains the orientation of the connection member 9, the wiper blade 11 thus remaining substantially vertical, as illustrated, as it moves back and forth across the windscreen 1 5.

Both main arm 1 and slave arm 3 are rectangular in cross-section and are formed from hollow outer members 17 and 19 and a core member 21 (see Fig. 2). Thus by moving one or both outer members 17. 19 relative to core member 21, the main and slave arms can be adjusted in length. The preselected positions of the outer and core members is maintained by screws 23 which engage through holes in the outer members 17, 19 and are screwed into threaded bores in core member 23. The illustrated embodiment provides for three possible lengths for the slave and main arms. However, any desired number of preselected lengths can of course be catered for merely by the provision of suitable holes and threaded bores in the outer and core members.Further, whilst screws secure the outer and core members together any suitable alternative means of securing their relative positions can of course be substituted.

Further adjustment of the illustrated wiper arm is possible by varying the spacing between the parallel slave arm 3 and main arm 1. This is simply effected by connecting the slave arm 3 to hole 25 (see Fig. 2) in the connection member 9 in contrast to the connection illustrated in Fig. 1. Whilst only one additional hole 25 is illustrated, any desired number of alternative holes can of course be provided in the connection member 9.

Thus, by virtue of the illustrated embodiment with three length positions and two possible spacings, the wiper arm is really six wiper arms in one and can be maintained on stock to be easily substituted for any of six original wiper arms. Further, as the slave arm 3 can be simply detached, parts of the wiper arm can be simply replaced if partial damage occurs, thus reducing operating costs.

To facilitate removal of the slave and main arms 1, 3 from the in situ location shown in Fig. 1, lugs 27 and 29 are provided, behind which a tool e.g. screwdriver, can be engaged to thus lever the arms from the usual splined drive shafts (not shown).

The present invention thus provides a virtually universal wiper arm which can be simply adjusted to be installed in place of a number of different wiper arms.

Claims

1. A wiper arm for use on a motor vehicle, comprising a main arm and a slave arm pivotally inter-connected, said arms being telescopic and securable at a number of predetermined lengths.

2. A wiper arm as claimed in claim 1, in which the main arm and slave arm are connected to opposite end regions of a connection member, one or both of the slave and main arms being detachably connected to the connection member and adjustable in position thereon to provide for different spacings between the main and slave arms.

3. A wiper arm as claimed in claim 1 or claim 2, in which the main and slave arms are connected to drive and freely movable pivots respectively.

4. A wiper arm as claimed in claim 3, in which the main and slave arms are connected to said pivots by splined connections.

5. A wiper arm as claimed in claim 3 or 4, in which the main and slave arms are provided with lugs which enable a tool to be engaged therewith for detachment of the wiper arm from a vehicle.

6. A wiper arm as claimed in any one of claims 1 to 5, in which both the main arm and the slave arm are formed from two hollow outer members and a core member which extends into each of said outer members.

7. A wiper arm as claimed in claim 6, in which the outer members are secured to the core member by screws.

8. A wiper arm as claimed in claim 7, in which the screws extend through holes in the outer member and engage in any one of a number of spaced apart bores provided along the length of the core member.

9. A wiper arm as claimed in any one of the preceding claims, in which both the slave arm and main arm are of rectangular cross section.

10. A wiper arm as claimed in any one of claims 6, 7 and 8, in which the outer members and core members are of rectangular cross section.

11. A wiper arm for use on a motor vehicle, constructed and arranged substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.