FIELD OF INVENTION
The present disclosure generally relates to the field of automobiles. Particularly, but not exclusively, the present disclosure relates to the construction and mechanism of a lock of a door handle for heavy-duty vehicles. Further, embodiments of the present disclosure disclose a door handle lock that requires less operating force and has a longer life.
BACKGROUND
The information in this section merely provides background information related to the present disclosure and may not constitute prior art(s).
Generally, vehicles such as, but not limited to, heavy duty trucks, excavators and the like are provided with cabins for an operator/driver to use the vehicle. Accessibility to the cabin of such vehicles is limited by means of a door. Conventionally, the door is provided with a door handle to operate the door and a latch mechanism is internally configured with the door handle for locking/unlocking the door.
As shown in Figure 1, a conventional door handle assembly comprises a movable door handle and a latch which may be configured with the door handle by means of a resiliency loaded lever or any suitable linkage/CAM lock. A pivoting lock is used to convert an outward motion of the handle during usage by the driver/user into an inward motion of the lever through a linking member which is riveted at one end to the handle and to the lever at the other end. The lever in turn transfers its motion to a latch assembly, which after a certain degree of rotation, opens the door latch, enabling to door to swing open. The linking member may also be

attached to a torsion spring which is installed at the central mounting position of the linking member with the fixed casing. Therefore, the action of the door handle is an auto-returning operation which brings the entire lock back to its original position once the door has been opened and the actuating force is removed from the door handle.
With further advancements, many locking mechanisms have also been added to the existing door handles. One such mechanism comprises a lock barrel assembly being mounted above the central mounting point of the linking member. The lock barrel is attached to a CAM at the bottom. Therefore, when a key is inserted into the lock and rotated, the CAM also rotates simultaneously. The CAM has a protrusion on its surface which changes its position with the rotation. The profile of the linking member is such that when the lock is 'LOCKED', the CAM and its protrusion inhibits the movement of the linking member, and the door handle cannot be moved. Consequently, the lever and latch cannot be moved, and door cannot be opened.
However, there are many problems associated with the existing door handles having a latch. A major disadvantage is that friction arises between the curved lever surface and the latch, resulting in rough operation of the door handle requiring more human effort. One more disadvantage is that the resting position of the lever on the latch is close to its pivoting point. Therefore, a longer distance has to be covered over the latch surface by the lever to generate enough torque and angular movement before the door is opened. Additionally, over a long period of time, the sliding contact between the lever and the latch can cause excessive wear and tear of the parts.
In other words, the researchers are constantly working to develop a door handle lock requiring less effort to use. More specifically, door handle lock that has less wear and tear and overcomes the one or more problems associated with the prior-art.

SUMMARY OF THE PRESENT DISCLOSURE
One or more drawbacks of conventional door handle lock as described in the prior art are overcome and additional advantages are provided through a door handle lock as claimed in the present disclosure. Additional features and advantages are realized through the technicalities of the present disclosure. Other embodiments and aspects of the disclosure are described in detail herein and are considered to be a part of the claimed disclosure.
In one non-limiting embodiment of the present disclosure, there is provided a door handle lock for vehicles. The door handle lock comprises a handle configured with a casing. A pivotally mounted, first member comprises a first end and a second end. The first end is coupled with the handle. The second end is movably coupled with a second member. The second member is pivotally mounted on the first member and comprises a roller. The roller is configured at a lower end of the second member. The roller is movable over a latch bar upon actuation of the first member by the handle to selectively unlock a latch of the vehicle.
In an embodiment, the first member is coupled with a resilient means.
In an embodiment, the resilient means is torsional spring.
In an embodiment, the first member is pivotally supported by a primary supporting member about a first pivot point.
In an embodiment, an upper end of the second member is coupled to one end of a secondary supporting member at a second pivot point.
In an embodiment, the second member is movable about the second pivot point upon actuation of the first member.
In an embodiment, the latch comprises the latch bar and a locking end.

In an embodiment, the locking end is engaged with a lock mechanism.
In an embodiment, the lock mechanism is generally in a locked condition.
In an embodiment, the second member is configured to move laterally along a horizontal axis XX upon actuation of first member such that the roller is movable over the latch bar of the latch.
In an embodiment, the latch bar is configured to move along axis YY upon motion of the roller and the locking end rotates about its centre.
In an embodiment, rotation of the locking end causes selective unlocking of the lock mechanism.
The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent with reference to the drawings and the following detailed description.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
The novel features and characteristics of the disclosure are set forth in the appended description. The disclosure itself, however, as well as a preferred mode of use, further objectives and advantages thereof, will best be understood by reference to the following detailed description of an illustrative embodiment when read in conjunction with the accompanying figures. One or more embodiments are now described, by way of example only, with reference to the accompanying figures wherein like reference numerals represent like elements and in which:
Figure 1 illustrates a section view of a conventional door handle having a latch lock.
Figure 2 illustrates a perspective view of the present door handle lock at operating condition, according to an embodiment of the present disclosure.

Figure 3 depicts a roller of the door handle lock, according to an embodiment of the present disclosure.
Figure 4 illustrates a front view of the present door handle lock whereby, the lock is in unactuated condition, according to an embodiment of the present disclosure.
Figure 5 illustrates a perspective view of the present door handle lock whereby, the lock is in the actuated condition, according to an embodiment of the present disclosure.
The figures depict embodiments of the disclosure for purposes of illustration only. One skilled in the art will readily recognize from the following description that alternative embodiments of the assemblies and methods illustrated herein may be employed without departing from the principles of the disclosure described herein.
DETAILED DESCRIPTION
While the invention is subject to various modifications and alternative forms, specific embodiment thereof has been shown by way of example in the figures and will be described below. It should be understood, however that it is not intended to limit the invention to the particular forms disclosed, but on the contrary, the invention is to cover all modifications, equivalents, and alternative falling within the spirit and scope of the invention as defined by the appended claims.
Before describing in detail, the various embodiments of the present disclosure it may be observed that the novelty and inventive step that are in accordance with a door handle lock for vehicles requires less efforts to use. It is to be noted that a person skilled in the art can be motivated from the present disclosure and can perform various modifications. However, such modifications should be construed within the scope of the invention.

Accordingly, the drawings are showing only those specific details that are pertinent to understanding the embodiments of the present disclosure so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having benefit of the description herein.
The terms "comprises", "comprising", or any other variations thereof, are intended to cover a non-exclusive inclusion, such that an assembly, setup, system, device that comprises a list of components does not include only those components but may include other components not expressly listed or inherent to such system or device or setup. In other words, one or more elements in the system or apparatus or device proceeded by "comprises a" does not, without more constraints, preclude the existence of other elements or additional elements in the assembly or system or apparatus. The following paragraphs explain present disclosure. The invention in respect of the same may be deduced accordingly.
Accordingly, it is an aim of the present disclosure to provide develop a user-friendly door handle lock for heavy duty vehicles that requires less effort during use.
Another aim of the present disclosure is to provide a door handle lock that is economical and has a longer life cycle.
Accordingly, the present disclosure provides a door lock handle for vehicles. In one non-limiting embodiment of the present disclosure, there is provided a door handle lock for heavy-duty vehicles. The door handle lock comprises a handle. The handle is configured with a casing. A pivotally mounted, first member comprises a first end and a second end. The first end is coupled with the handle. The second end is movably coupled with a second member. The second member is pivotally mounted on the first member and comprises a roller. The roller is configured at a lower end of the second member. The roller is movable over a latch bar upon actuation of the first member by the handle to selectively unlock a latch of the vehicle. The first member is coupled with a resilient means. The resilient means is torsional spring. The first member is pivotally supported by a

primary supporting member about a first pivot point (PI). An upper end of the second member is coupled to one end of a secondary supporting member at a second pivot point (P2). The second member is movable about the second pivot point (P2) upon actuation of the first member. The latch comprises the latch bar and a locking end. The locking end is engaged with a lock mechanism. The lock mechanism is generally in a locked condition. The second member is configured to move laterally along a horizontal axis XX upon actuation of first member such that the roller is movable over the latch bar of the latch. The latch bar is configured to move along axis YY upon motion of the roller and the locking end rotates about its centre. Rotation of the locking end causes selective unlocking of the lock mechanism.
Accordingly, the present disclosure relates to the construction of a door lock handle for heavy duty vehicles. Further, embodiments of the present disclosure disclose a door lock handle lock requires less effort to unlock the door of the vehicle.
Reference will now be made to a door lock handle for vehicles which is explained with the help of figures. The figures are for the purpose of illustration only and should not be construed as limitations on the assembly and mechanism of the present disclosure. Wherever possible, referral numerals will be used to refer to the same or like parts.
Figures 2 to 5 illustrate a door handle lock (100) for heavy duty vehicles according to the present disclosure. The door handle lock (100) is mounted on a door of the vehicle. In an embodiment of the present disclosure, the door handle lock (100) is configured to unlock the door of the vehicle with less efforts by a driver/user. The door handle lock (100) comprises, amongst other components, a casing (2) being attached on the door of the vehicle. The casing (2) may be mounted on the door of vehicle by means of screw/rivets and the like. The

configuration of the casing (2) may be variable depending on the requirement of the manufacturer, make of the vehicle etc.
As shown in figure 2 and 3, the door handle lock (100) comprises a handle (1), a first member (3) coupled to the handle (1), a second member (6) coupled with the first member (3) and a latch (10). The handle (1) is located at one side of the casing (2). The handle (1) has one end attached to the casing (2). Another end of the handle (1) is coupled with the first member. The handle, the first member, the second member and the latch are attached to one another in such a way that defines a 4-bar linkage. The 4-bar linkage is configured with a roller (9) for actuating the latch (10) to unlock the door of the vehicle.
As shown in figure 2, the resiliency energized handle (1) is resiliency energized and disposed to a casing (2) such that the handle (1) is actuable by a user. A resilient force of the handle always tends to move the handle to its unactuated condition. Disposed another side of the casing (2) is the first member (3) being configured with a torsion spring (not shown) which is the said resilient means. The torsion spring is coupled to a portion of the first member (3) in contact an end of a primary supporting member (4). A pivot point (PI) is formed at the point of contact of the primary supporting member (4) and the first member (3). The other end of the primary supporting member (4) may be secured to the casing (2) by means of a screw (5).
As shown in figure 3, the first member (3) comprises a first end (3a) and a second end (3b). The first end (3a) is connected to the handle (1). The second end (3b) of the first member (3) is in connection with the second member (6). During actuation of the door handle lock (100), the actuation force from the door handle (1) is transmitted to the second member (6) via the first member (3).
In an embodiment, the first member (3) may be connected with the second member (6) via securing means such as rivets. The second member (6) is

supported in the casing (2) by means of a secondary supporting member (8). The secondary supporting member (8) is configured to movably support the second member (6) about a second pivot point (P2) such the roller (9) attached to an end of the second member (6) moves laterally along axis XX during actuation of the said door handle lock (100).
As shown in figure 5, the latch (10) has a locking end (10a) which may be engaged with a locking means of the door. The locking end (10a) is configured to rotate about its centre so as to 'UNLOCK' the door of the vehicle. Formed perpendicularly to the locking end (10a) is a latch bar (10b).
In the mounted condition, the roller (9) is supported on the latch bar (10b) and is configured to push the bar (10b) downwardly along axis YY during actuation of the said door handle lock (100).
As shown in Figures 4 and 5, the door handle lock (100) is generally in an unactuated condition corresponding to a 'LOCKED' condition of the door. When the user actuates the handle (1), the actuation force is transmitted from the handle (1) to the second member (6) via the first member (3). As the handle (1) is moved away from the casing (2), the second member (6) is pushed down on the latch bar (10b) of the latch (10) and the roller (9) rolls over the latch bar (10b) towards the locking end (10a). The movement of the roller (9) exerts a torque which causes an angular movement of the locking end (10a) of the latch (10). Thus, in a non-limiting manner, the locking end (10a) rotates such that the door of the vehicle is unlocked. Thereby, less effort is required to open the door of the vehicle causing convenience to the user. Further, as there is no friction due to absence of sliding parts, there is less wear and tear and the life of the door handle lock (100) is improved significantly. When the user removes the actuation force from the handle (1), due to spring action, the handle returns to the unactuated condition and the locking end (10a) rotates to reach the 'LOCKED' condition.

In one embodiment, there may be provided a lock (11) to lock the door handle lock (100) by means of a key. The lock (11) has a keyway. The keyway is located at the one side of the casing. The key may be provided to insert in the keyway of the lock to lock the door of the vehicle.
List of reference numerals:

100 Door handle lock
1 Handle
2 Casing 10
3 First member
3a First end
3b Second end
4 Primary supporting member 15
5 Screw
6 Second member
8 Second supporting member
9 Roller ">0
10 Latch
10b Latch bar
10a Locking end
11 Lock
25

Equivalents:
With respect to the use of substantially any plural and/or singular terms herein, those having skill in the art can translate from the plural to the singular and/or from the singular to the plural as is appropriate to the context and/or application. The various singular/plural permutations may be expressly set forth herein for sake of clarity.
It will be understood by those within the art that, in general, terms used herein, and especially in the appended claims (e.g., bodies of the appended claims) are generally intended as "open" terms (e.g., the term "having" should be interpreted as "having at least," etc.). It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding, the following appended claims may contain usage of the introductory phrases "at least one" and "one or more" to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles "a" or "an" limits any particular claim containing such introduced claim recitation to inventions containing only one such recitation, even when the same claim includes the introductory phrases "one or more" or "at least one" and indefinite articles such as "a" or "an" (e.g., "a" and/or "an" should typically be interpreted to mean "at least one" or "one or more"); the same holds true for the use of definite articles used to introduce claim recitations. In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should typically be interpreted to mean at least the recited number (e.g., the bare recitation of "two recitations," without other modifiers, typically means at least two recitations, or two or more recitations). It will be further understood by those within the art that virtually any disjunctive word and/or phrase presenting two or more alternative terms, whether in the description, claims, or drawings, should be understood to contemplate the

possibilities of including one of the terms, either of the terms, or both terms. For example, the phrase "A or B" will be understood to include the possibilities of "A" or "B" or "A and B."
While various aspects and embodiments have been disclosed herein, other aspects and embodiments will be apparent to those skilled in the art. The various aspects and embodiments disclosed herein are for purposes of illustration and are not intended to be limiting, with the true scope and spirit being indicated by the following claims.

We claim
1. A door handle lock (100) comprising:
a handle (1) being configured with a casing (2);
a pivotally mounted first member (3) comprising:
a first end (3a) being coupled with the handle (1);
a second end (3b) being movably coupled with a second member (6);
the second member (6) being pivotally mounted on the first member (3) and comprises a roller (9) being configured at a lower end of the second member (6); wherein, the roller (9) is movable over a latch bar (10b) upon actuation of first member (3) by the handle (1) to selectively unlock a latch (10) of the vehicle
2. The door handle lock (100) as claimed in claim 1, wherein the first member (3) is coupled with a resilient means.
3. The door handle lock (100) as claimed in claim 9, wherein the resilient means is torsional spring.
4. The door handle lock (100) as claimed in claim 1, wherein the first member (3) is pivotally supported by a primary supporting member (4) about a first pivot point (PI).
5. The door handle lock (100) as claimed in claim 1, wherein an upper end of the second member (6) is coupled to one end of a secondary supporting member (8) at a second pivot point (P2).

6. The door handle lock (100) as claimed in claim 1, wherein the second member (6) is movable about the second pivot point (P2) upon actuation of the first member (3).
7. The door handle lock (100) as claimed in claim 1, wherein the latch (10) comprises the latch bar (10b) and a locking end (10a).
8. The door handle lock (100) as claimed in claim 1, wherein the locking end (10a) is engaged with a lock mechanism.
9. The door handle lock (100) as claimed in claim 1, wherein the lock mechanism is generally in a locked condition.
10. The door handle lock as claimed in claim 1, wherein the second member (6) is configured to move laterally along a horizontal axis XX upon actuation of first member (3) such that the roller (9) is movable over the latch bar (10b) of the latch (10).
11. The door handle lock as claimed in claim 6, wherein the latch bar (10b) is configured to move along axis YY upon motion of the roller (9) and the locking end (10b) rotates about its centre.
12. The door handle lock (100) as claimed in claim 1, wherein rotation of the locking end (10a) causes selective unlocking of the lock mechanism.