DESC:SCRAPER MECHANISM FOR ROLLER

Field of invention:

The present invention relates to pneumatic tyre rollers and more particularly relates to a scraper mechanism for roller.

Background of the invention:

Pneumatic tyre roller (PTR) is used for providing sealing asphalt layer in road construction and airport runways. Front tyres are mounted with suspension cylinder and it allows suspension of +/- 100 mm, steering linkages are connected with suspension cylinder, so the tyres are turning along with one end of the suspension cylinder during steering. The hot asphalt used for road construction is viscous and having adhesive property. The rubber tyre get hard and uneven surface due to the adhered asphalt and gravel during road construction. This hard and uneven surface will affect the road quality. Scraper attachments are used to clean the adhered hot asphalt with gravel from the tyre of PTR with the help of water sprinkler system. In such mechanism, the water acts as isolating agent. Scrapers need not contact with the tyre surface during travel mode so the scraper has to be locked in such a way that it should not touch the tyre surface.

Current arrangement of scraping system does not have the contour so that the scraper has contact with tyre in the small segment and the life of scraper is less. Locking arrangement in current systems is not rigid and it cause damage of scraper during machine movement. Sprinkler system is mounted on a chassis and the water sprinkling is not effective during steering of wheel and suspension.

Deficiencies of prior art:

1. The flat coir mats are used in rollers and a scraper loaded with self-weight having scraping performance less and hence the road quality is getting affected.
2. Locking of scrapers when they are not in use is not rigid and hence it tends to damage the tyre surface.
3. The mounting arrangement of the scrapers does not accommodate various scraper arrangements such as rubber and brush scraper.
4. Sprinkler arrangements are mounted as fixed member and hence sprinkling is not effective during tyre steering and suspension.
5. In some prior art documents, stoppers are not provided, hence scraper exerted more force against tyre.

Accordingly, there exists a need to provide a scraper device for rollers that overcomes the mentioned drawbacks of the prior arts.

Objects of the invention:

An object of the present invention is to perform complete scraping of adhered asphalt, gravel and mud from tyres of a roller.

Another object of the present invention is to provide arrangement for locking a scraper device, when not in use, without touching the tyres of the roller.

Yet, another object of the present invention is to provide option for accommodating different types of scraper attachment.

Summary of the invention:

Accordingly, the present invention provides a scraper mechanism for a roller. The roller has tyres with a contour configured thereon and are mounted with a suspension cylinder. The scraper mechanism is assembled at front side of the suspension cylinder, such that the mechanism suspends and turns along with the suspension cylinder. The scraper mechanism comprises a mounting plate, a first frame, a mounting bracket, a scraper arrangement, a locking arrangement and a stopping system. The mounting plate is fixed on the suspension cylinder. The first frame is mounted on the mounting plate by a plurality of mounting holes provided thereon. The mounting bracket is fixed on the first frame. The mounting bracket has a first pair of mounting arms fitted thereon. A plurality of holes is provided at one side of the first pair of mounting arms. A torsion spring is arranged in the first pair of mounting arms by using a mounting pin, such that one end of the torsion spring is fitted with any suitable hole of the plurality of holes. The mounting pin is locked by a split pin.

The scraper arrangement comprises a second frame, a third frame and a scraper. The second frame has a second pair of mounting arms fitted thereon. The second pair of mounting arms is fixed on the mounting pin such that other end of the torsion spring gets fitted in a notch provided on one of the second pair of mounting arms, thereby allowing the scraper arrangement to swing towards front and back. The third frame, configured with a contour, is assembled with the second frame. The scraper is fitted on the contour of the third frame in a tangential contact with surface of the tyre. The scraper is configured with contour having profile closely matching to the profile of the contour of the tyre for having positive contact with the surface of the tyre.

The locking arrangement is arranged in the first pair of mounting arms. The locking arrangement includes a scraper lock pin, a compression spring, a collar and a dowel pin connected with each other such that the scraper lock pin is loaded by the compression spring and is stopped by the collar and the dowel pin. The locking arrangement is capable of locking the scraper arrangement. The stopping system having a stop screw and a stopper plate helps to prevent excess pressure of scraper with tyre surface.

In an operation, as the roller is moved, the scrapers are subjected to torsional spring load, as one end of the torsion spring is fitted with suitable hole of the first pair of mounting arms and the other end of the torsion spring is fitted in the notch in one of the second pair of mounting arms. Thus, the torsional force exerted by the torsion spring pushes the scraper against the tyre, thereby maintaining positive contact between tyre and the scraper. The scraper starts cleaning the adhered asphalt and gravel from the tyre surface.

Brief description of drawings:

The objects and advantages of the present invention will become apparent when the disclosure is read in conjunction with the following figures, wherein

Figure 1 shows a front view of a scraper mechanism assembled on a suspension cylinder of a roller, in accordance with the present invention;

Figure 2 shows a side view of the scraper mechanism assembled on the suspension cylinder of the roller, in accordance with the present invention;

Figure 2A shows a closer view of the scraper mechanism of the roller, when in use, in accordance with the present invention;

Figure 2B shows a closer view of the scraper mechanism of the roller, when not in use, in accordance with the present invention;

Figure 3 shows an exploded view of a scraper attachment of the scraper mechanism of the roller, in accordance with the present invention;

Figure 4 shows an exploded view of the scraper mechanism of the roller, in accordance with the present invention;

Figure 4A shows an isometric view of a mounting bracket and torsion spring position adjustment of the scraper mechanism, in accordance with the present invention;

Figure 5 shows a sectional view of scraper engagement with tyre, in accordance with the present invention;

Figure 6 shows a section view of a stopper system of the scraper mechanism, in accordance with the present invention; and

Figure 7 shows an isometric view of a scraper mechanism having rubber scraper with angular contact, in accordance with an alternate embodiment of the present invention.

Detailed description of the invention:

The foregoing objects of the present invention are accomplished and the problems and shortcomings associated with the prior art, techniques and approaches are overcome by the present invention as described below in the preferred embodiments.

The present invention provides a pre-loaded contoured scraper mechanism for roller that can clean the adhered asphalt and gravel from the tyre surface. The mechanism includes spring loaded contoured coir scraper with modular mounting.

The present invention is illustrated with reference to the accompanying drawings, throughout which reference numbers indicate corresponding parts in the various figures. These reference numbers are shown in bracket in the following description and the table given below.

Table:
Component Name Component Number
Suspension cylinder 1
Mounting plate 2
First frame 3
Mounting bracket 4
Second frame 5
Third frame 6
Contour of the third frame 6a
Scraper 7
Contour of the Scraper 7a
Mounting pin 8
Split pin 10
Torsion spring 9
Scraper lock pin 11
Dowel pin 12
Compression spring 13
Collar 14
Tyre 15
Tyre contour 15a
Sprinkler system 16
Stop screw 17
Stopper plate 18
Scraper arrangement 20
First pair of Mounting arms 21A
Second pair of Mounting arms 21B
Plurality of holes of First pair of Mounting arms 22
Notch of Second pair of Mounting arms 23
Slot of Second pair of Mounting arms 24
Locking arrangement 30
Scraper mechanism 100
Referring to the figures 1 to 7, a scraper mechanism (100) (herein after referred to as “the mechanism (100)”) for a roller is shown in accordance with the present invention. Tyres (15) of the roller are mounted with a suspension cylinder (1). The tyres (15) are configured with a contour (15a) (shown in figure 5). The contour (15a) is known as “Tyre Arc Radius”. Steering linkages (not shown) are connected with the suspension cylinder (1) at rear side thereof, such that the tyres (15) turn along with the suspension cylinder (1) during steering. The mechanism (100) is assembled at front side of the suspension cylinder (1), such that the mechanism (100) suspends and turns along with the suspension cylinder (1). Hence, scraping performance is not affected during suspension and wheel steering. The mechanism (100) comprises a mounting plate (2), a first frame (3), a mounting bracket (4), a scraper arrangement (20), a locking arrangement (30) and a stopping system (not numbered).

The mounting plate (2) is fixed on the suspension cylinder (1) by welding. The first frame (3) is an intermediate frame provided with a plurality of mounting holes (not numbered). The plurality of mounting holes is used to mount the first frame (3) on the mounting plate (2) at front end thereof by bolts (not numbered). The first frame (3) interconnects the suspension cylinder (1) and the scraper arrangement (20) through the locking arrangement (30). The mounting bracket (4) is fixed on the first frame (3) at front side thereof by bolts (not numbered). The mounting bracket (4) has a first pair of mounting arms (21A) fitted thereon.

The first pair of mounting arms (21A) is provided with a plurality of holes (22) at one side thereof (as shown in Figure 4A). A torsion spring (9) is arranged in the first pair of mounting arms (21A) by using a mounting pin (8). One end of the torsion spring (9) is fitted with any suitable hole of the plurality of holes (22) to adjust the force acting on the scraper arrangement (20) through adjustment of locating position of the torsion spring (9). Thus, the scraper arrangement (20) can be swung towards front and back.

The scraper arrangement (20) comprises a second frame (5), a third frame (6) and a scraper (7). The second frame (5) is scraper mounting frame having a second pair of mounting arms (21B) fitted thereon. The second pair of mounting arms (21B) is fixed on the mounting pin (8) such that other end of the torsion spring (9) gets fitted in a notch (23) (as shown in Figure 4) provided on one of the second pair of mounting arms (21B). Specifically, the second frame (5) is pivoted by the mounting pin (8) with the pairs of mounting arms (21A, 21B). The mounting pin (8) is locked by a split pin (10). The pairs of mounting arms (21A, 21B) hold the scraper arrangement (20) and also provide support thereto.

The third frame (6) is assembled with the second frame (5) by bolts (not numbered). The third frame (6) is provided with a plurality of holes (not numbered) to hold the scraper (7) thereon. Specifically, the third frame (6) is configured with a contour (6a) thereon to hold the scraper (7).

The scraper (7) is fitted in such a way that the scraper (7) can have a tangential contact with surface of the tyre (15). The scraper (7) is configured with contour (7a) thereon. In an embodiment, the contour (7a) has profile similar or closely matching to the profile of the contour (15a) of the tyre (15). The scraper arrangement (20) is engaged in such a way that the scrapers (7) have sufficient contact with the tyres (15). The scrapers (7) are subjected to torsional spring load, as one end the torsion spring (9) is fitted with suitable hole (22) of the first pair of mounting arms (21A) and the other end of the torsion spring (9) is fitted in the notch (23) in one of the second pair of mounting arms (21B). Thus, the torsional force exerted by the torsion spring (9) pushes the scraper (7) against the tyre (15), thereby maintaining positive contact between tyre (15) and the scraper (7). In the specific embodiment, the scraper (7) is a flexible coir mat. In an alternative embodiment (as shown in fig. 7), the scraper (7) includes rubber pads.

The locking arrangement (30) is arranged in the first pair of mounting arms (21A). Specifically, the first pair of mounting arms (21A) holds the locking arrangement (30) therein holds. The locking arrangement (30) comprises a scraper lock pin (11), a compression spring (13), a collar (14) and a dowel pin (12). The scraper lock pin (11) is loaded by the compression spring (13) and is stopped by the collar (14) and the dowel pin (12). The locking arrangement (30) is capable of locking the scraper arrangement (20). The scraper arrangement (20) can be swung towards front and locked during travel operation. One part of the second pair of mounting arms (21B) has a slot (24) configured thereon (as shown in Figure 4) for locking. The scraper lock pin (11) is pulled and engaged on the slot (24) for holding the scraper arrangement (20), when not in use condition as shown in figure 2B. Hence, the scraper (7) keeps away from the tyre (15) and does not have contact with the tyre (15) during travel operation. The scraper lock pin (11) is pulled and gets disengaged from the scraper arrangement (20) to unlock the scraper (7) in use condition as shown in figure 2A.

The first frame (3) has a provision for arrangement of the stopping system. The stopping system consists of a stop screw (17) and a stopper plate (18). The stop screw (17) can be adjusted towards front and back. When the scraper arrangement (20) is adjusted, so that the scraper (7) touches the tyre (15), then the stop screw (17) is adjusted in such a way that the stop screw (17) touches the stopper plate (18). So that, the scraper arrangement (20) does not move beyond the limit set by the stop screw (17). This limit can be adjusted by adjusting the stop screw (17). The stopping system prevents excess pressure of the scraper (7) with surface of the tyre (15) and also limits the position thereof.

The first frame (3) also has a provision for mounting a sprinkler system (16). The sprinkler system (16) is mounted on the first frame (3) and it is connected with the suspension cylinder (1). The sprinkler system (16) moves along with suspension cylinder (1) for sprinkling water, thereby cleaning the tyre surface. Accordingly, the sprinkling system (16) is operable during tyre steering and suspension.

Again referring to the figures 1 to 7, an operation of the scraper mechanism (100) for roller in accordance with the present invention is described. The operation is described in conjunction with the mechanism (100).

The torsion spring (9) exerts force to the scraper (7) to have positive contact with the surface of the tyre (15). The scrapers (7) are subjected to the spring load so that a positive contact between the tyre (15) and the scraper (7) is maintained. So, during unlocked condition of the scraper arrangement (20), the scraper (7) has a good contact, with tyre surface for achieving a complete scraping of the tyre surface (15). Hence, as the roller is moved, the scrapers (7) starts cleaning the adhered asphalt and gravel from the tyre surface. Simultaneously, the sprinkler system (16) moves along with the suspension cylinder (1) so that sprinkling is not affected during suspension and steering of wheel. The locking arrangement (30) provides a rigid and easy locking of the scraper (7) during travel mode. The locking arrangement (30) helps the scrapers (7) to hold such that they do not have contact with tyre (15) when they are not in use and it helps in increasing life of scraper (7).

Advantages of the invention:

1. The mechanism (100) is capable of keeping the scraper (7) with the contour as same as the tyre (15).
2. The mechanism (100) locks the scraper arrangement (20) when it is not in use such that scraper (7) does not touch the tyre (15).
3. The mechanism (100) allows the scraper arrangement (20) and the sprinkler system (16) to move along with the suspension cylinder (1).
4. The mechanism (100) is flexible to accommodate different types of scraper attachment.

The foregoing descriptions of specific embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the present invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the present invention and its practical application, and to thereby enable others skilled in the art to best utilize the present invention and various embodiments with various modifications as are suited to the particular use contemplated. It is understood that various omissions and substitutions of equivalents are contemplated as circumstances may suggest or render expedient, but such omissions and substitutions are intended to cover the application or implementation without departing from the scope of the claims of the present invention.
,CLAIMS:We claim:

1. A scraper mechanism (100) for a roller, the roller having tyres (15) configured with a contour (15a) and mounted with a suspension cylinder (1), the scraper mechanism (100) assembled at front side of the suspension cylinder (1), such that the mechanism (100) suspends and turns along with the suspension cylinder (1), the scraper mechanism (100) comprising:
a mounting plate (2) fixed on the suspension cylinder (1);
a first frame (3) provided with a plurality of mounting holes for mounting the first frame (3) on the mounting plate (2) at front end thereof;
a mounting bracket (4) fixed on the first frame (3) at front side thereof, the mounting bracket (4) having a first pair of mounting arms (21A) fitted thereon, the first pair of mounting arms (21A) having,
• a plurality of holes (22) provided at one side thereof,
• a torsion spring (9) arranged therein by using a mounting pin (8), such that one end of the torsion spring (9) fitted with any suitable hole of the plurality of holes (22);
a scraper arrangement (20) comprising
• a second frame (5) having a second pair of mounting arms (21B) fitted thereon, wherein the second pair of mounting arms (21B) is fixed on the mounting pin (8) such that other end of the torsion spring (9) gets fitted in a notch (23) provided on one part of the second pair of mounting arms (21B) for pivoting the second frame (5) by the mounting pin (8) with the pairs of mounting arms (21A, 21B), thereby allowing the scraper arrangement (20) to swing towards front and back,
• a third frame (6) assembled with the second frame (5), the third frame (6) configured with a contour (6a) thereon, and
• a scraper (7) fitted on the contour (6a) of the third frame (6) in a tangential contact with surface of the tyre (15), the scraper (7) is configured with contour (7a) thereon;
a locking arrangement (30) arranged in the first pair of mounting arms (21A), the locking arrangement (30) comprising a scraper lock pin (11), a compression spring (13), a collar (14) and a dowel pin (12) connected with each other such that the scraper lock pin (11) is loaded by the compression spring (13) and is stopped by the collar (14) and the dowel pin (12); and
a stopping system arranged on the first frame (3), the stopping system consisting of a stop screw (17) and a stopper plate (18), wherein the stopping system prevents excess pressure of scraper (7) with tyre surface;
wherein, as the roller is moved, the torsion spring (9) exerts force to the scraper (7) to have positive contact with the surface of the tyre (15), the scrapers (7) start cleaning the adhered asphalt and gravel from the tyre surface.

2. The scraper mechanism (100) for the roller claimed in claim 1, wherein the contour (7a) has profile closely matching to the profile of the contour (15a) of the tyre (15) for having positive contact with the surface of the tyre (15).

3. The scraper mechanism (100) for the roller claimed in claim 1, wherein the mounting pin (8) is locked by a split pin (10).

4. The scraper mechanism (100) for the roller claimed in claim 1, wherein the force acting on the scraper arrangement (20) is adjusted through adjustment of locating position of the torsion spring (9) in the plurality of holes (22) provided on the one side of the first pair of mounting arms (21A).

5. The scraper mechanism (100) for the roller claimed in claim 1, wherein the scrapers (7) are subjected to the spring load for maintaining a positive contact between the tyre (15) and the scraper (7).

6. The scraper mechanism (100) for the roller claimed in claim 1, wherein the scrapers (7) are selected from coir mats, rubber pads.

7. The scraper mechanism (100) for the roller claimed in claim 1, wherein one part of the second pair of mounting arms (21B) has a slot (24) configured thereon for engaging the scraper lock pin (11) thereon, thereby holding the scraper arrangement (20), when not in use condition and keeping the scraper (7) away from the tyre (15) during travel operation.

8. The scraper mechanism (100) for the roller as claimed in claim 1, wherein a sprinkler system (16) is mounted on the first frame (3) and is connected with the suspension cylinder (1) such that the sprinkler system (16) moves along with suspension cylinder (1) during suspension and steering of wheel for sprinkling water, thereby cleaning the tyre surface.

Dated this 15th day of November 2019

Madhavi Vajirakar
(Agent for Applicant)
(IN/PA-2337)