DESC:ASSEMBLING SYSTEM FOR VALVE SEAT AND VALVE GUIDE
FIELD OF INVENTION
Present invention is related to system and method for assembling components in any cylinder head of internal combustion engine. Particularly, assembling valve seat and valve guide in cylinder head of internal combustion engine.
CROSS-REFERENCE TO RELATED APPLICATIONS
This invention takes priority from an earlier filed provisional patent application no. 201921048487 filed on November 27, 2019; which is incorporated herein as reference.
BACKGROUND OF THE INVENTION
Assembling or pressing valve seat and valve guide in the cylinder head of an internal combustion engine is one of the most important process in engine assembly. This process have direct effect on performance of the engine due to effect on intake and exhaust valve operations. The valve seat is a critical component of an engine, if it is improperly positioned or oriented during assembly, valve leakage may occur which adversely affects the engine compression ratio and therefore affecting the engine efficiency, performance, exhaust emissions, and engine life. A valve guide is a cylindrical piece of metal, pressed into the cylinder head, with the valve reciprocating inside it. Hence perfect alignment of the valve guide in valve guide hole of cylinder head has equal importance as valve seat. Conventionally, manufacturers follow below steps to assemble valve seat and valve guide into the cylinder head. Valve seat is loaded on valve seat adapter provide at bottom of the press tool. Locating cylinder head in dowel pins. Further, loading valve guide on to the valve guide adaptor provided on the top of the press tool. Pressing valve guide from the top first then valve seat from the bottom of the cylinder head. Both pressing operations are done by means of actuators provided at top and bottom side of the press tool. In this system and method, as the valve seat and valve guides are to be fitted at an angle. An inclined surface plate or fixture or taper block or change plate is required to hold cylinder head in pressing position. Taper block or change plate retains the location of the component. Angle of inclination of the inclined surface of the taper block or change plate is corresponds to valve axis angle. The mentioned system and method has some limitations and disadvantage. There are few factors which influences above method or process such as valve axis angle, after pressing height of valve guide, center distance of dowel holes, valve center distance, profile of valve seat. Since different cylinder head has different design, there may be difference in each of the factor mentioned above.
These factors demand for different fixtures, taper block, valve seat adapters, valve guide adapters, change plates for different cylinder head design in a press tool. Changing the taper block or change plate is time consuming process.
Time required to changing these components while setup change is huge which largely contributes idle time of the total engine assembly process. Also there is a possibility of uneven application force while pressing of valve seat and valve guide which leads to misalignment of the valve assembly which may affect engine performance as mentioned in above paragraph. Thus it was needed to provide a flexible valve seat and valve guide press tool system and method which can suit all cylinder heads and solve above mentioned problems.
OBJECTIVE
It is an objective of the present invention to provide a flexible assembling system for assembling a valve seat & a valve guide in any cylinder head. It is another objective of the present invention to provide a assembling system to assemble the valve guide and the valve seat in single setup. Yet another object of the invention to provide a method for assembling the valve seat and the valve guide using assembling system mentioned above. Yet another object of invention to improve concentricity and avoid misalignment of the valve seat & the valve guide during assembly.
SUMMARY OF THE INVENTION
Above mentioned objectives are achieved by providing flexible assembling system to assemble the valve seat and the valve guide in the cylinder head of an internal combustion engine comprise of at least a valve seat adapter to hold the valve seat before assembling into the cylinder head provided, where the valve seat adapter provided at one end of the assembling system; at least a valve guide adapter to hold the valve guide before pressing in to the cylinder head, where the valve guide adapter provided on the other end of the assembly system. Preferably, the valve seat is provided at top end and the valve guide provided at bottom end of the assembling system. The valve guide adapter may be movable. Movement of the valve guide adapter may be restricted by a stopper mechanism. A support means is provided to support the cylinder head and advantageously adapt various valve angles of different types of cylinder heads. The support mechanism may be moveable and operated by a hydraulic or a pneumatic or a servo or a manual mechanism. A spring retained locating pin may be provided concentric with the valve seat and the valve seat adaptor. An actuator provided to move the valve seat adapter along with locating pin towards pressing direction. The actuator may be of hydraulic or pneumatic or servo or manual type. The Cylinder head may be roughly located on the valve guide adapter wherein the cylinder head is supported by the valve guide adapter on spot face for the valve spring seat of the cylinder head.
In another embodiment of the present invention, a center distance adjustment mechanism is provided to assemble the valve seat and the valve guide in multiple valve cylinder heads such as four valve cylinder head. Here, the center distance may be a distance between the two adjacent valve axes. In case of four valve type cylinder heads, two valve guide adapters may be provided with indexing slide at bottom of the press tool. A horizontal actuator may be of hydraulic or pneumatic or servo or manual type, moves second valve guide adapter over indexing slide by keeping first valve guide adapter fixed. Once desired position is achieved, a clamping or a breaking element holds second valve guide adapter tight in its position. In this way, the center distance adjusting mechanism acts as an auto-indexing unit.
Yet another embodiment of the present invention, in case of multiple valve cylinder heads such as four valve cylinder head, Auto loading mechanism for valve seat on valve seat adapter may be provided. One valve seat may be loaded manually over the valve seat pressing adapter & another valve seat may be loaded on auto loader, which after assembling of first valve seat will automatically load standby valve seat on pressing adapter.
Above mentioned system may be used to assemble the valve seat and the valve guide in the cylinder head of an internal combustion engine through following steps of method or following method may be implemented using above system.
a. Load the valve seat on the valve seat adapter,
b. Load the valve guide on the valve guide adapter,
c. Restrict movement of the valve guide adapter by means of the stopper mechanism,
d. Load cylinder head on the valve guide adapter such that the cylinder head is supported on spot face for valve spring seat of the cylinder head,
e. Provide support to the cylinder head by support means, such that valve guide parent bore or parent hole of cylinder head is roughly aligned to assembling axis,
f. Move the valve seat adapter along with a locating pin towards pressing direction by means of an actuator, such that the locating pin enters in the valve guide parent bore or parent hole of the cylinder head and the cylinder head gets aligned to pressing axis or valve guide bore axis or assembling axis,
g. Move actuator further towards pressing direction to press valve seat through valve seat adaptor,
h. After completion of pressing of valve seat, retract actuator in opposite direction of the pressing direction,
i. Remove support means,
j. Remove restriction provided to valve guide adapter by removing stopper mechanism,
k. Move actuator in pressing direction further this will move cylinder head towards valve guide adapter such that valve guide gets pressed in to the cylinder head,
l. After completion of valve guide pressing, retract the actuator to its original position.
System and method mentioned above provides tooling which presses both the valve guide & the valve seat in single setup. Inserting locating pin in valve guide bore or parent hole provides easy alignment of pressing axis with the cylinder head. The system and method uses spot face for spring seat of the cylinder head to support the cylinder head on the valve guide adapter which is always normal to the valve guide bore or parent hole or pressing axis. The system and method can be used for any type of cylinder head without any requirement of taper block to support that particular cylinder head. There is no need of any setup changes due to change in valve angle, change in location center distance or changes in any other parameters mentioned above. This feature provides flexibility in the valve seat and the valve guide pressing process. Time required for changing taper block or inclined surface plate, valve seat adapter or any other component according to changes in cylinder head design eliminated. Hence, ideal time in the engine assembly process reduces considerably. Also this system reduces pressing forces considerably. Which in turn reduces stresses generated in cylinder head.
BRIEF DESCRIPTION OF FIGURES
In order to understand the invention and to see how it can be carried out in practice, non-limiting examples and embodiments will now be described with reference to the accompanying drawings, in which:
Fig. 1 represents Press tool system according to preferred embodiment of the present invention;
Fig. 2 represents positioning of cylinder head with preferred embodiment of the present invention;
Fig. 3 represents stopper mechanism according preferred embodiment of the present invention;
Fig. 4 represents center distance adjustment mechanism according to preferred embodiment.
DETAILED DESCRIPTION OF FIGURES
Embodiments of present invention will now be explained with the help of FIG.s herein below. All the aspects described herein will be better appreciated and understood when considered in conjunction with the following description and the accompanying drawings. It should be understood, however, that the following descriptions, while indicating preferred embodiments and numerous specific details thereof, are given by way of illustration and not of limitation. Many changes and modifications may be made within the scope herein without departing from the spirit and scope thereof, and the present invention herein includes all such modifications.
Fig. 1 represents system and method for assembling a valve seat and a valve guide in a cylinder head of an internal combustion engine according to one of the embodiments of the present invention. According to preferred embodiment of the present invention, the assembling system may be a press tool. The system and method comprised of a press tool 101, a valve seat adapter 102 to hold valve seat 103 before pressing provided on top side of the press tool 101. Further, the press tool 101 comprised of a valve guide adapter 104 to hold a valve guide 105 before pressing into the cylinder head 106 provided on bottom side of the press tool 101. The valve guide adapter 104 may be movable. A Support means 107 provided to support the cylinder head and advantageously adapt various valve angles. The support mechanism 107 may be moveable and operated by a hydraulic or pneumatic or servo or manual mechanism. A spring retained locating pin 108 may be provided concentric with valve seat 103 and valve seat adaptor 102 as shown in figure. The Actuator 109 provided to move the valve seat adapter 102 along with the locating pin 108 towards pressing direction. The actuator may be of hydraulic or pneumatic or servo or manual type.
Fig. 2 shows the positioning of the cylinder head on to the valve guide adapter 104 according present invention. The cylinder head 106 may be positioned on the valve guide adapter 104 in such a way that cylinder head 106 may be supported by the valve guide adapter 104 on the valve spring seat surface 201 of the cylinder head 106.
Fig. 3 shows the stopper mechanism according to one of the embodiment of the present invention. Movement of the valve guide adapter 104 may be restricted by the stopper mechanism 301 may be actuated hydraulic, pneumatic, servo or manual system 303.
Fig. 4 shows center distance adjusting mechanism in case of multiple valve cylinder head. In case of four valve type cylinder head 106 according to another embodiment of the present invention, two valve guide adapters 104 and 110 with valve guides 105 and 111 may be provided with indexing slide 402 at bottom of the press tool 101. The cylinder head 106 may have positioned on to the valve guides adapters 104 and 110 as shown in Fig. 4. According to present invention a center distance adjusting mechanism 401 may be provided to connect and move the second valve guide adapter 110 over indexing slide 402 by keeping first valve guide adapter 104 fixed. Once desired position is achieved, a clamping or breaking element 403 holds second valve guide adapter 104 tight in its position. In this way, center distance adjusting mechanism 401 acts as an auto-indexing unit. Its main advantage is convenience in operation & accuracy in positioning.
According to the present invention, above mentioned system may be implemented through method explained below.
Load the valve guide 105 on the valve guide adapter 104 provided on bottom side of the press tool 101 manually or by any means. Further, load the valve seat 103 in the valve seat adapter 102 provided on top side of the press tool 101 manually or by any means. According to present invention, load cylinder head 106 on the valve guide adapter 104 such that the valve guide adapter 104 supports the cylinder head 106 through spring seat surface 201 of the cylinder head 106. Provide support to the cylinder head by means of the support mechanism 107 provided to adapt various valve angles. The support mechanism 107 may be of hydraulic or pneumatic or servo or manual type. Then, move the spring retained the locating pin 108 towards pressing direction by means of the actuator 109 provided on the top of the press tool 101. Where, the said actuator 109 may be of hydraulic or pneumatic or servo or manual type. The locating pin 108, the valve seat 103 and the valve seat adaptor 102 are concentrically mounted on the actuator 109. Move down the spring retained locating pin 108 by means of the actuator 109 such that the locating pin 108 enters valve guide bore or parent hole 202 of the cylinder head 106 in which the valve seat 103 and the valve guide 105 to be pressed. As an effect, the cylinder head 106 gets align in to pressing axis. In other words, the cylinder head 106 gets aligned to the axis 203 of the valve seat 103, the valve seat adapter 102, the locating pin 108, the valve guide 105 and the valve guide adapter 104 or to the pressing axis. Movement of the actuator 109 towards pressing direction causes pressing of the valve seat 103 in the cylinder head 106. After completion of the valve seat pressing process, stop movement of the actuator 109 and retract it by unit distance in opposite direction of pressing direction. While, remove the support mechanism 107 provided to support the cylinder head 106. Then, remove the stopper mechanism 301 provided to restrict downward movement of the valve guide adapter 104. The stopper mechanism 301 may be operated by hydraulic or pneumatic or servo or manual systems 303. In order to avoid free falling of the cylinder head 106 after removal of stopper 301, the valve guide adapters 104 are supported by compression spring 112 in it. In the next step, move the actuator 109 in downward direction again and start pressing the cylinder head 106 through valve seat surface. As an effect, the valve guide 105 loaded on the valve guide adapter 104 get pressed into the parent hole 202. After completion of pressing of the valve guide 105 in the valve guide hole or parent hole 202, move the actuator 109 back to its original position.
The system and method provided according the present invention required no change of any setup for different cylinder head. The system and method assembles the valve seat and the valve guide into the cylinder head in single setup which is the most important advantage of the present invention. This leads to reduction of ideal time in the overall assembling process of the engine. Possibility of miss alignment of the valve guide, the valve seat and hence, the valve is eliminated by system and method provided by the present invention.
Following flowchart shows the detailed steps followed in the method provided by present invention. Flowchart shows all the steps with its conditions and decisions. The system for assembling valve seat and valve guide may be follow below flowchart while assembling valve seat and valve guide in the cylinder head according to one of the preferred embodiment of the present invention.
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,CLAIMS:1. An assembling system (101) to assemble a valve seat (103) and a valve guide (105) in a cylinder head (106) of an internal combustion engine, wherein the system comprises;
a. at least a valve seat holding means (102) to hold the valve seat (103) before assembling into the cylinder head (106);
b. at least a valve guide holding means (104) to hold the valve guide (105) before assembling into the cylinder head (106);
c. a support means (107) to support the cylinder head (106);
d. a locating means (108) for aligning the cylinder head with a pressing axis;
e. an actuator (109) to move the valve seat holding means (102) along with the locating means (108).
2. The assembling system (101) as claimed in claim 1, wherein the valve seat holding means is a valve seat adaptor (102) and the valve guide holding means is the valve guide adaptor (104).
3. The assembling system (101) as claimed in claim 2, comprising a stopper mechanism (301) to restrict movement of the valve guide adapter (104).
4. The assembling system (101) as claimed in claim 2, wherein the valve seat adapter (102) provided at one end of the assembling system (101) and the valve guide adapter (104) provided on the other end of the assembly system (101).
5. The assembling system (101) as claimed in claim 4, wherein the valve seat adaptor (102) is provided at top end and the valve guide adaptor (104) is provided at bottom end of the assembling system (101).
6. The assembling system (101) as claimed in claim 1, wherein the valve guide adapter (104) is movable parallel to bore hole or parent hole (202).
7. The assembling system (101) as claimed in claim 1, wherein the support mechanism (107) is moveable and operated by hydraulic or pneumatic or servo or manual mechanism.
8. The assembling system (101) as claimed in claim 1, wherein the locating means is a spring or pneumatically retained locating pin (108) and the locating pin is arranged concentric with the valve seat (103) and the valve guide (105).
9. The assembling system (101) as claimed in claim 1, wherein the actuator (109) is of hydraulic or pneumatic or servo or manual type.
10. The assembling system (101) as claimed in claim 1, the cylinder head (106) is located on the valve guide adapter (104) wherein the cylinder head is supported by the valve guide adapter on spot face (201) for valve spring seat of the cylinder head.
11. The assembling system (101) as claimed in claim 1, wherein the support means (107) is capable to support variety of the cylinder head (106) having different valve angles.
12. The assembling system (101) as claimed in claim 1, wherein a center distance adjustment mechanism (401) is provided to assemble the valve seat and the valve guide in multiple valve cylinder heads.
13. The assembling system (101) as claimed in claim 12, wherein a center distance adjustment (401) comprises an indexing slide (402) movable by means of an actuator; the actuator is of hydraulic or pneumatic or servo or manual type.
14. The assembling system (101) as claimed in claim 1, wherein an auto loading mechanism is provided for loading the valve seat (103) on the valve seat adapter (102).
15. An assembling method to assemble a valve seat and a valve guide in a cylinder head of an internal combustion engine, wherein the assembling method comprising steps of;
a. Loading of the valve seat (103) on a valve seat adapter (102),
b. Loading the valve guide (105) on the valve guide adapter (104),
c. Restricting movement of the valve guide adapter (104) by means of a stopper mechanism (301),
d. Loading the cylinder head (106) on the valve guide adapter (104); the cylinder head is supported on spot face (201) for valve spring seat of the cylinder head (106),
e. Supporting the cylinder head by a support means (107); a valve guide parent bore or parent hole (202) of cylinder head is roughly aligned to assembling axis (203).
f. Moving the valve seat adapter (102) along with a locating pin (108) towards pressing direction by means of an actuator (109), the locating pin enters in the valve guide parent bore or parent hole (202) of the cylinder head and the cylinder head gets aligned to the pressing axis or valve guide bore axis or assembling axis (203),
g. Moving actuator (109) further towards pressing direction to press the valve seat (103) through the valve seat adaptor (102),
h. Retracting the actuator (109) in opposite direction of the pressing direction,
i. Removing the support means (107),
j. Removing restriction provided to valve guide adapter by removing stopper mechanism (301),
k. Moving the actuator (109) in pressing direction; as an effect cylinder head moves towards the valve guide adapter (104) and the valve guide (105) gets pressed into the cylinder head