WO2000069570A1

WO2000069570A1 - Wheel equipped carriage for a forward and backward movement along an essentially linear track in connection to a painting automate

Info

Publication number: WO2000069570A1
Application number: PCT/SE2000/000960
Authority: WO
Inventors: Patric Bengtsson
Original assignee: Patric & Brothers Ab
Priority date: 1999-05-12
Filing date: 2000-05-12
Publication date: 2000-11-23
Also published as: AU4966100A; SE9901749L; SE522007C2; SE9901749D0

Abstract

The present invention relates to a wheel equipped carriage for a forward and a backward movement along an essentially linear track in connection to a painting automate. The invention is characterised in that carriage comprises two rectangular plates attached back to back with intermediate washer means and with 45° bent edge portions, whereby a resilient spring action of the central portion of each plate will be allowed when one or several of the wheels in the wheel pairs in connection to each corner of the carriage will pass unevenness on the linear track or a build up layer on the same track, whereby the wheels in each pair of wheels will rotate around shafts being mutually adjusted and bear during a permanently resilient action on each track, respectively.

Description

Wheel equipped Carriage ^{f or a} forward and backward movement along an essentially linear track in connection to a painting automate.

The present invention relates to a wheel equipped carriage for a forward and a backward movement along an essentially linear track in connection to a painting automata, which carriage moves during a heavy acceleration and deceleration, often in an environment where a heap of paint and powder rests on the roller surfaces of the linear track for the wheels of said carriage can not be prevented.

Prior art painting automates use a column with carriages being movable thereon. Said carriages being proportionately big and heavy. This is the case especially for carriages having paint sprayers mounted thereon. The object of a painting automate is to efficiently apply a protecting film onto a component in the shortest possible way. The component is hung up in a special box, or is allowed to pass a spray station carried by a conveyor and wherein evacuation means and paint recycling means often are arranged in connection to the paint box. The carriage with one or more spray devices will carry out a predetermined and for the component suited movement during spraying of paint (electrostatically charged powder) or of any other protecting/coating material. Thus it is previously known that the carriage with spray device will move along a vertical column of square pipes. The carriage will move along the sides of the vertical column with the aid of four pair of wheels, one pair along each side of the column. The spay device may be pivotally arranged at the carriage. Furthermore the column can be arranged horizontally displaceable, which means that spray means on the movable carriage and the column may cover a surface of a x-/y co-ordinate system, i.e. the spray automate is well suited to coat bigger components. The carriage and the spray device will move in a preprogrammed pattern of movement adapted for each component, i.e. during repeated accelerations and retardations of the carriage and the spray device. Provided that the column itself is also movable sideways it will be exposed to inertia forces during a shifting sideways. Thus the transmission mechanisms used to move said carriage and maybe column will be exposed to heavy stresses and components forming part of said mechanisms must often be replaced. It is important to keep the weight/masses of the components of the automate as low and small as possible. This to enhance the reaction speed of the automate and to decrease the appearing inertia forces. Thus a more exact guiding and a more rapid movement of carriage/spray device of said spray automate is a condition to increase the production at the same time as the loss of paint or powder will be minimised.

The carriage according to the invention is not restricted to be used just in a direct connection to a spray device, but can very well also be used at a working station prior to the coating itself, i.e. together with a sensor, which may be a camera forming part of a digitalized picture handling system, which rapidly and correctly will move vertically and horizontally. A horizontal movement can be achieved by a movement of the component, while the vertical movement will take place as the carriage and the sensing or scanning means move. Hereby the shape and the size of the component will be registered as well as of the surfaces to be treated. This scanning method may done so that data regarding position, shape and size of the surfaces to be treated will be stored in a memory in connection to a microprocessor controlling the function of the painting automate. The more exact information there is regarding the component to be treated the more exact the proceeding surface treatment will be, i.e. with a minimal of losses both regarding time and paint.

DE-A-4 009 386 disclose a wheel equipped carriage for a movement forwards and backwards along an essentially linear track in connection to a painting automate. This known carriage is complex in design and is heavy compared to the carriage according to the invention. A counterweight is used to balance the weight of the carriage, which means that there are essential masses to be accelerated and decelerated in connection to the forward and backward movement of the carriage. The carriage and the co-operating linear track are quite complicated in their constructions and it is not possible to simply dismount the cover plates to remove the paint coatings or layers from said tracks inside the vertical column. Further this prior art carriage is not suited to take and withstand loads from all directions, but will in principle just take loads directed forwards/backwards .

The main object of the present invention is to obtain a wheel equipped carriage being movable along an essentially linear track, where both the carriage and the track may have an extremely simple construction which can be made very compact and also light. This will minimise the inertia forces, which have to be handled in acceleration and deceleration and will spare the transmission system moving the carriage and maybe the column. At a paining automate this means that rapid movements of the spray device carrying or scanning carriage may be performed with essentially less inertia forces performing during acceleration and deceleration.

An other object according to the invention is to obtain a combination of a wheel equipped carriage and linear track securing a loose free and resilient bearing of the wheels of the carriage to bridge unevenness, if any, when the carriage is moved forwards and backwards along said track, whereby the wheels have a possibility to spring away for a heavy an uneven distributed coating on the tracks.

Yet another object with the present invention is to obtain a wheel equipped carriage which is self-adjusting and centred in the working position along said linear track, whereby the carriage and the track together efficiently can take up loads coming from almost all directions.

Another object with the invention is to obtain a combination of wheel equipped carriage/linear track for painting automates where the linear track very easily can be inspected and cleaned without a need to dismount covering plates.

The objects stated above will be obtained according to the invention by the wheel equipped carriage for a forward and backward movement along said essentially linear track in connection to a painting automate having the patent clauses mentioned in the claims.

The invention will be described below in connection to a painting automate having a spray device for paint or powder arranged on said movable carriage.

When the bent shanks of the profiled U-girder having a first section with an angle of 45° towards the rib of the girder, a straight shank portion (90° towards the rib of the girder) and with a second section with an angle of 135° towards the rib of the girder, and at the same time as the wheels of the carriage are arranged two and two and bear on the inclined sections of the shanks, a stable and self-adjusting carriage moving in the profiled U- girder is obtained. The wheel carrying part of the carriage is made of two rectangular plates with edge portions bent 45° and bonded back to back with intermediate washers, whereby on pair of wheels is arranged in connection to each corner and the bent edge portions of the wheel carrying part, which means that the wheels in each pair of wheels will run around shafts being mutually perpendicular. The washers will enable a spring action between the wheel carrying edge portions at the plates being arranged back to back and which forms said carriage. En preload on said wheels against the track is also possible and will eliminate the need for an individual setting of all the eight wheels in the carriage to obtain a loose free and steady guiding between the carriage and the track.

The invention will now be described in connection to an embodiment shown in the drawings; where

Fig. la is a schematic side view of a known column in a painting automate having a carriage bearing on and movable along said column without any spray device;

Fig. lb is a comparing side view of a vertical column in a painting automate having a carriage bearing on and movable along said column according to the present invention;

Fig. 2 is a view from below of a detached carriage with a holder means for a spray equipment;

Fig. 3 is a view along 3 - 3 in fig. lb showing the positioning of the carriage in the column and the holder means for (a not shown) painting equipment; and where Fig. 4 is a view from above of the carriage with wheels but without any holder means.

In fig. la is shown the vertical column la of a painting automate 1 of prior art with a usable vertical stroke of 1700 mm. The total height of this column is 2600 mm and the total weight is 250 kg. The weight of the carriage, the guiding with wheels and holder means, generally designed 2a, for the spray equipment is about 9 kg. This can be compared with a vertical column lb with carriage and guiding according to the invention - shown in fig. lb - having a maximal height of 2000 mm with the same useful stroke, a total weight of about 70 kg, and where the weight for carriage, wheels, guidings and holder means (2b) is about 3 kg.

In fig. 2 a view from below of a detached carriage 3 with a holder means 2 for spraying equipment (not shown). The carriage 3 is here made of two identically and bent plates 4 and 5 being assembled by bolts 6, 7 and with adjacent washers 6a, 7a. This will form a small outer gap 8a, 8b allowing said bent and wheel carrying edge portions of the plates 4 and 5 to spring a little. Using the same bolt fitting (6, 7) the holder means 2 is mounted at the carriage 3 with the aid of a profile bent plate 9.

In fig. 3 a carriage 3 with a holder means 2 mounted in the track/guide B arranged with the column. This track/guide B is attached at the inside of column lb which has two side slits, through which the two ends of the profiled plate 9 extend carrying the holder means 2. In fig. 3 an upper lid 10 with an attached gearwheel 11 intended to carry a chain is shown. This chain is attached with the carriage/the profiled plate and is driven by a motor (not shown) arranged below.

Fig. 4 shows the carriage 3 with mounted wheels A and without any holder means. The wheels positions give a very compact carriage being stable and which together with the vertical column and the holder means give a splendid guiding to the combination carriage/holder means.

The invention is not restricted to the shown embodiment, but modifications can be made within the scope of the following claims.

Claims

C L A I M S

1. A wheel equipped carriage for a forward and a backward movement along an essentially linear track in connection to a painting automate, characterised in that carriage comprises two rectangular plates attached back to back with intermediate washer means and with 45° bent edge portions, whereby a resilient spring action of the central portion of each plate will be allowed when one or several of the wheels in the wheel pairs in connection to each corner of the carriage will pass unevenness on the linear track or a build up layer on the same track, whereby the wheels in each pair of wheels will rotate around shafts being mutually adjusted and bear during a permanently resilient action on each track, respectively.

2. A combination of a wheel equipped carriage according to claim 1 and a linear track, along which the carriage intended to run, characterised in that the track consists of a continuos profiled iron U-girder, onto inclined shank portions of which the wheels of the carriage is from the inside arranged with an essential 45° direction towards the length axis and transverse axis of the carriage, respectively.

3. A combination according to claim 2, characterised in that the bent shanks of the profiled U-girder have a first section extending 45° towards the rib of the girder, a straight shank portion (90° towards the rib of the girder) and a second section extending 135° towards the rib of the girder, whereby the wheels of the carriage is arranged in couples and bear on the inclined sections of the shanks.

4. A method to use a wheel equipped carriage according to claim 1, characterised in that the carriage is equipped with a sensor means which will register contours and surfaces of items passing or moving relatively the carriage and sensor means during the movement forward and backward of the carriage, whereby information regarding position, shape and size of the surfaces registered will be stored in a memory in connection to a microprocessor controlling the paint outlet from the painting automate, whereby stored information is used to in the most efficient way control the outlet of paint from the painting automate later on.