DESC:FORM 2

THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENT RULES, 2003

COMPLETE SPECIFICATION
(See Section 10 and Rule 13)

Title of invention:
COTTER-LESS PUSHROD VALVE TRAIN WITH LASH ADJUSTER SYSTEM

Applicant:
BEML Limited
A company Incorporated in India under the Companies Act, 1956
Having address:
BEML Soudha, 23/1, 4th Main,
Sampangirama Nagar, Bengaluru - 560 027,
Karnataka, India

The following specification particularly describes the invention and the manner in which it is to be performed.
CROSS-REFERENCE TO RELATED APPLICATIONS AND PRIORITY
[001] The present invention claims priority from Indian patent Provisional Application 202141011321 filed on 17 March 2021.
TECHNICAL FIELD
[002] The present invention relates to a valve train and lash adjuster and more particularly it relates to a cotter-less pushrod valve train with the lash adjuster system.
BACKGROUND
[003] The valve train is a mechanical system that controls operation of valves in an internal combustion engine. In existing system, a pair of valve cotter is used to lock valve stem with spring retainer to ensure smooth functioning of engine. However, when the cotter joint is tightened in the socket and spigot slot, the cotter joint is exposed to maximum shear stresses. Further, if the cotter gets loose, then the cotter may bend. Therefore, valve drop and piston hitting lead to catastrophic engine failures during engine running conditions occurs. Furthermore, in the existing systems a manual adjusting screw is used for adjusting the valve clearance during service, which consumes more time for servicing and makes servicing process more complicated.
[004] The existing design of lash adjuster system along with adjusting screw (100) is shown is Figure 1. The existing system comprises a cotter (102) and a separate upper valve seat (104). As the existing design comprises the manual adjusting screw (100) for adjusting the valve clearance during service, leads to error prone due to manual interventions. Further, in reference with the Figure 2, a conventional assembly (200) is illustrated in which the cotter (102), the separate upper valve seat (104), a spring (106) and a valve (108) is shown. The conventional assembly is having problem of the cotter (102) jump from valve, especially in heavy vehicles.
[005] Therefore, there is a need of an efficient system to achieve maximum endurance of the valve train and to provide automatic lash adjuster.
SUMMARY
[006] Before the present system and method are described, it is to be understood that this application is not limited to the particular machine or an apparatus, and methodologies described, as there can be multiple possible embodiments that are not expressly illustrated in the present disclosures. It is also to be understood that the terminology used in the description is for the purpose of describing the particular versions or embodiments only, and is not intended to limit the scope of the present application. This summary is provided to introduce aspects related to cotter-less pushrod valve train with lash adjuster system. The aspects are further elaborated as below in the detailed description. This summary is not intended to identify essential features of the proposed subject matter nor is it intended for use in determining or limiting the scope of the proposed subject matter.
[007] The present subject matter described herein, in general, relates to a system for cotter-less pushrod valve train with lash adjuster. The system comprises a rocker arm configured to a crosshead to operate on a valve. An integrated upper valve seat configured with plurality of segments of upper valve seat. An integral actuation sub-system is configured in between the pushrod and the rocker arm in order to maintain a clearance.
STATEMENT OF INVENTION
[008] Accordingly, the present subject matter discloses a system for cotter-less pushrod valve train with lash adjuster. The system comprises a rocker arm configured to a crosshead to operate on a valve. An integrated upper valve seat configured with plurality of segments of upper valve seat. An integral actuation sub-system is configured in between the pushrod and the rocker arm in order to maintain a clearance. The integrated upper valve seat is configured from integration of cotter and separate upper valve seat. The integral actuation sub-system is configured with an oil passage from a shaft of the rocker arm to feed the oil or lubricant to a hydraulic element with a plunger for performing actuations.
BRIEF DESCRIPTION OF THE DRAWINGS
[009] The foregoing summary, as well as the following detailed description of embodiments, is better understood when read in conjunction with the appended drawing. For illustrating the disclosure, there is shown in the present document example constructions of the disclosure, however, the disclosure is not limited to the specific methods and apparatus disclosed in the document and the drawing.
[010] The detailed description is described with reference to the accompanying figure. In the figure, the left-most digit(s) of a reference number identifies the figure in which the reference number first appears. The same numbers are used throughout the drawing to refer like features and components.
[011] Figure 1 illustrates an existing design of the lash adjuster system, in accordance with an embodiment of the invention;
[012] Figure 2 illustrates a conventional assembly of a cotter, a separate upper valve seat, a spring and a valve, in accordance with an embodiment of the invention;
[013] Figure 3 illustrates a cotter-less pushrod valve train with lash adjuster system, in accordance with an embodiment of the invention;
[014] Figure 4 illustrates a detailed schematic of the cotter-less pushrod valve, in accordance with the embodiment of the invention; and
[015] Figure 5 illustrates the details of an integrated upper valve seat, in accordance with the embodiment of the invention.
[016] The figures depicts various embodiments of the present disclosure for purposes of illustration only. One skilled in the art will readily recognize from the following discussion that alternative embodiments of the structures and methods illustrated herein may be employed without departing from the principles of the disclosure described herein.
DETAILED DESCRIPTION
[017] Some embodiments of this disclosure, illustrating all its features, will now be discussed in detail. The words "comprising", “having”, and "including," and other forms thereof, are intended to be equivalent in meaning and be open ended in that an item or items following any one of these words is not meant to be an exhaustive listing of such item or items, or meant to be limited to only the listed item or items. Although any systems and methods similar or equivalent to those described herein can be used in the practice or testing of embodiments of the present disclosure, the exemplary, systems and methods are now described. The disclosed embodiments are merely exemplary of the disclosure, which may be embodied in various forms.
[018] Various modifications to the embodiment will be readily apparent to those skilled in the art and the generic principles herein may be applied to other embodiments. However, one of ordinary skill in the art will readily recognize that the present disclosure is not intended to be limited to the embodiments illustrated, but is to be accorded the widest scope consistent with the principles and features described herein.
[019] The present subject matter relates a cotter-less pushrod valve train with a lash adjuster system. Now referring to Figure 3, wherein a cotter-less pushrod valve train with a lash adjuster system (300) is illustrated. Also, referring to Figure 4, wherein the detailed cotter-less pushrod valve is illustrated. The system (300) comprises a rocker arm (302), a crosshead (304), clearance (306), a pushrod (308), an integral actuation sub-system (310), a valve (108), a hydraulic element (312), one segment of upper valve seat (314) and a plunger (320). An oil passage (318) from a shaft (332) of the rocker arm (302) is feeding the oil or lubricant to the hydraulic element (312) with a plunger (320) for actuation. The pre-set oil pressure within the hydraulic element (312) helps to maintain a desired clearance (306) for the smooth engine operation.
[020] Further, referring to Figure 5, wherein details of an integrated upper valve seat (316) is illustrated. The in-built cotter- upper valve seat consists of a plurality of a male tenon (328) and a female tenon (330) for allowing assembly. The plurality of segments (314) are configured with the male tenon (328) and the female tenon (330) on each end of the segment (314) to form the integrated upper valve seat (316) on securely mounting one segment beside other. The integrated upper valve seat (316) is configured to securely mount the valve (108). Further, the segment (314) is configured with in-built cotter formed by a concentric groove (322) with an inner diameter (324) and an outer diameter (326).
[021] In an exemplary embodiment, the integral actuation sub-system (308) is configured in between the pushrod (308) and the rocker arm (302) in order to maintain a desired clearance (306). The integral actuation sub-system (310) consists of the oil passage (318) from the shaft (332) of the rocker arm (302) to feed the oil or lubricant to the hydraulic element (312) with a plunger (320) for actuation.
[022] In another exemplary embodiment, the integral actuation sub-system (310) is configured to the rocker arm (302) and introduces the in-built cotter-upper valve seat (here also referred as Integrated Upper Valve Seat) (316). The in-built cotter- upper valve seat consists of the plurality of male tenon (328) and female tenon (330) which allows assembly of the in-built cotter-upper valve seat.
[023] In another embodiment, a system (300) for cotter-less pushrod valve train with lash adjuster comprises a rocker arm (302) configured to a crosshead (304) to operate on a valve (108). An integrated upper valve seat (316) configured with plurality of segments of upper valve seat (314) and an integral actuation sub-system (310) is configured in between the pushrod (308) and the rocker arm (302) in order to maintain a clearance (306).
[024] Further, the integrated upper valve seat (316) is configured from integration of the cotter (102) and the separate upper valve seat (104). The integral actuation sub-system (310) is configured with an oil passage (318) from a shaft (332) of the rocker arm (302) to feed the oil or lubricant to a hydraulic element (312) with a plunger (320) for performing actuations. The oil pressure of the hydraulic element (312) is configured to be pre-set for maintaining the desired clearance (306) for smooth engine operation. The plurality of segments (314) are configured with a male tenon (328) and a female tenon (330) on each end of the segment (314) to form the integrated upper valve seat (316) when mounted one segment beside other.
[025] Furthermore, the integrated upper valve seat (316) is configured to securely mount the valve (108). The segment (314) is configured with in-built cotter formed by a concentric groove (322) with an inner diameter of concentric groove (324) and an outer diameter of concentric groove (326).
[026] Further, the invention can be used in Off-Highway Engine applications, where cylinder head cover is often very difficult to access due to space availability in the machine. However, not limited to the same.
[027] Exemplary embodiments discussed above may provide certain advantages. Though not required to practice aspects of the disclosure, these advantages may include those provided by the following features.
[028] Some embodiments of the system may reduce failure issues like cotter jump, valve drop and piston hitting in heavy-duty off-highway engine applications.
[029] Some embodiments of the system may minimize the regular checking and adjustment operations of valve train.
[030] Part No. Part Name
100 Adjusting Screw
102 Cotter
104 Separate Upper Valve Seat
106 Spring
108 Valve
200 Conventional Assembly (with cotter and separate upper valve seat)
300 System
302 Rocker Arm
304 Crosshead
306 Clearance
308 Pushrod
310 Integral Actuation Sub-System
312 Hydraulic Element
314 One Segment of Upper Valve Seat
316 Integrated Upper Valve Seat
318 Oil Passage
320 Plunger
322 Concentric Groove
324 Inner Diameter of Concentric Groove
326 Outer Diameter of Concentric Groove
328 Male Tenon
330 Female Tenon
332 Shaft
,CLAIMS:
1. A system (300) for cotter-less pushrod valve train with lash adjuster comprises:
a rocker arm (302) configured to a crosshead (304) to operate on a valve (108);
an integrated upper valve seat (316) configured with plurality of segments (314) to form an integrated upper valve seat (316); and
an integral actuation sub-system (310) is configured in between the pushrod (308) and the rocker arm (302) in order to maintain a clearance (306).
2. The system (300) for the cotter-less pushrod valve train with lash adjuster as claimed in claim 1, wherein said integrated upper valve seat (316) is configured from integration of cotter and separate upper valve seat.
3. The system (300) for the cotter-less pushrod valve train with lash adjuster as claimed in claim 1, wherein the integral actuation sub-system (310) is configured with an oil passage (318) from a shaft (332) of the rocker are (302) to feed the oil or lubricant to a hydraulic element (312) with a plunger (320) for performing actuations.
4. The system (300) for the cotter-less pushrod valve train with lash adjuster as claimed in claim 1, wherein oil pressure of the hydraulic element (312) is configured to be pre-set for maintaining the desired clearance (306) for smooth engine operation.
5. The system (300) for the cotter-less pushrod valve train with lash adjuster as claimed in claim 1, wherein said plurality of segments (314) are configured with a male tenon (328) and a female tenon (330) on each end of the segment (314) to form the integrated upper valve seat (316) on securely mounting one segment beside other.
6. The system (300) for the cotter-less pushrod valve train with lash adjuster as claimed in claim 1, wherein said integrated upper valve seat (316) is configured to securely mount the valve (108).
7. The system (300) for the cotter-less pushrod valve train with lash adjuster as claimed in claim 1, wherein the segment (314) is configured with in-built cotter formed by a concentric groove (322) with an inner diameter of concentric groove (324) and an outer diameter of concentric groove (326).