KR102680396B1 - Jig which is used in CVVD manufacturing process - Google Patents

Abstract

The present invention provides a jig for supporting and moving a lifter housing assembly of a CVVD device of an automobile, wherein the jig includes a base; An intermediate plate mounted on the base; An upper plate installed on the middle plate to maintain the distance and plane of the lifter housing assembly until assembly is completed; A pair of bosses mounted on the sides of the top plate; and a lifter housing center fixing unit supported by the boss and accommodating the lifter housing assembly.

Description

Jig which is used in CVVD manufacturing process}

The present invention relates to a jig used in the CVVD manufacturing process. In particular, the present invention relates to a jig that firmly supports a lifter housing.

A car's internal combustion engine generates power by taking fuel and air into the combustion chamber and burning them. When taking in air, the intake valve and exhaust valve are operated alternately by driving the camshaft. The optimal operation of the intake and exhaust valves varies depending on the rotational speed of the engine, and appropriate lifting operations must be performed and the opening and closing timing of the valves must be adjusted accordingly. For this purpose, multiple valve driving cams were designed or continuously variable valve lift (CVVL) or continuously variable valve timing (CVVT) were developed, but they have the disadvantages of being complex in structure, difficult to control, and expensive.

Therefore, a continuous variable valve duration (CVVD) device that can immediately adjust the duration of the valve, that is, the time from opening to closing, according to the operating state of the engine has been developed and is being applied.

Patent No. 10-2020-0073858 discloses a CVVD device 10' mounted on the camshaft 30' of the engine 1' as shown in FIG. 1. The CVVD device 10' has a structure in which a pair of modules consisting of a lifter housing 90' mounted on a guide bracket 134' are connected to a control shaft 102', both ends of which are connected to a control worm 104'. It consists of A cap 40 and cams 71' and 72' are arranged on the camshaft 30', and lower portions of the cams 71' and 72' are connected to intake and exhaust valves (not shown).

Looking at the lifter housing 90' and related structures disclosed in the above patent, as shown in FIG. 2, between the two guide holes 94' in the center of the guide wall 92' on the upper part of the lifter housing 90'. A worm wheel (50') is mounted on the guide shaft (132'), which has threads (130') formed through the guide hole (94'), and the sliding holes (96) on both sides around the guide hole (94') are fastened to the guide shaft (132'). '), a sliding shaft 135' is fastened thereto. The control worm 104' meshes with the worm wheel 50'. Here, when the control worm 104' rotates by driving an actuator (not shown), the worm wheel 50' moves along the thread 130' of the guide shaft 132' and pushes the guide wall 92' to move the camshaft. (30') The relative position of the lifter housing 90' with respect to the central axis is changed, and the rotational speed of the cams 71' and 72' with respect to the cam shaft 30' is changed according to their phases.

In this CVVD device, it is especially essential that the lifter housing and related members be manufactured with high precision with minimal errors. Conventionally, in the assembly of the guide bracket and lifter housing, and the assembly of the lifter housing, worm wheel, guide shaft, and sliding shaft, the related parts were placed in a work jig and the general assembly method of “bolt-nut combination” was selected according to the work sequence. However, although this process can produce a rough CVVD device, there are limitations in producing a high-precision, dense, stable and reliable CVVD device without changes in transportation, installation, and operation after manufacturing.

The applicants and inventors have put in a lot of effort over the years to establish a new process to develop a precise and stable CVVD device for the first time in Korea and abroad. The present invention was developed based on the results of this work.

The purpose of the present invention is to provide a jig as a platform that supports the lifter housing assembly during the assembly process of a CVVD device for an automobile and can be moved to the next process.

In order to achieve the above-described object, the present invention provides a jig for supporting and moving a lifter housing assembly of a CVVD device of an automobile, wherein the jig includes a base; An intermediate plate mounted on the base; An upper plate installed on the middle plate to maintain the distance and plane of the lifter housing assembly until assembly is completed; A pair of bosses mounted on the sides of the top plate; and a lifter housing center fixing unit supported by the boss and accommodating the lifter housing assembly.

The lifter housing center fixing unit includes a bar, and an outer surface of the bar may be tapered to accommodate a needle bearing press-fitted into an opening of the lifter housing.

The upper plate has a slot drilled in the center, and a narrow extension is formed from each corner around the slot. In order to keep the position of the lifter housing stable and prevent it from rotating during work, a seating block is installed on the upper part adjacent to the slot of the upper plate. can be installed.

By mounting a ball plunger on each of the extension parts, the height of the ball can be flexibly adjusted when the lifter housing is moved.

According to the present invention, it provides an environment in which the CVVD device is assembled while maintaining the same conditions as those installed on the engine of an automobile, and at the same time, it serves as a moving and supporting means to firmly and accurately support and accommodate the lifter housing assembly from the beginning to the end of the process. It has the effect of providing a jig.

1 shows a conventional CVVD device;
Figure 2 is a view showing a lifter housing and related members in the prior art;
3 is a flow chart showing the process flow of a CVVD device according to an embodiment of the present invention;
Figure 4 is a diagram showing the assembled state of CVVD device-related parts to help understand each process of Figure 3;
Figure 5 is an overall perspective view of the jig of the present invention;
Figure 6 is a top view of the jig of Figure 5; and
Figure 7 is a perspective view showing the assembly of the lifter housing of Figure 4f mounted on the jig of the present invention.

The purpose and effects of the present invention, and technical configurations for achieving them, will become clear by referring to the embodiments described in detail below along with the accompanying drawings. In describing the present invention, if it is determined that a detailed description of a known function or configuration may unnecessarily obscure the gist of the present invention, the detailed description will be omitted.

Throughout the specification, when a part is said to “include” a certain element, this means that it may further include other elements rather than excluding other elements, unless specifically stated to the contrary. Meanwhile, in an embodiment of the present invention, each component, functional block, or means may be composed of one or more lower components.

<Overview of manufacturing process of CVVD device (1)>

FIG. 3 is a flowchart showing the process flow of the CVVD device 1 according to an embodiment of the present invention, and FIG. 4 shows the assembled state of parts related to the CVVD device 1 to help understand each process in FIG. 3. It is a drawing. The parts that make up the CVVD device 1 are manufactured and supplied in advance through casting, injection, drawing, or forging processes.

First, the needle bearing 20 is press-fitted into the lifter housing 2 (S10; Figure 4a). Two lifter housings (2) are required for the CVVD device (1).

Next, each lifter housing (2) is coupled to the guide bracket (3) (S12; Figure 4b).

Next, assemble the lifter housing (2) by penetrating the sliding shaft (4) on both sides (S14; Figure 4c).

Next, the worm wheel (5) is mounted in the central space between the guide walls of the lifter housing (2) (S16; Figure 4d).

Next, assemble the guide shaft (6) by passing it through the center of the lifter housing (2) and through the inside of the worm wheel (5) (S18; Figure 4e).

Finally, the CVVD device 1 is structurally integrated by connecting the control shaft 7 and the sub-assembly to bridge the two guide brackets 3 (S20).

Most of the processes of the present invention are performed automatically according to the order in which major parts are installed and assembled without operator intervention. To assemble the shaft and the worm wheel, a robot arm specially manufactured for the implementation of the present invention is used.

In manufacturing the CVVD device (1), a jig is required as a platform to support and transport the lifter housing (2) and guide bracket (3) throughout the process. The main members of the CVVD device (1) must be stably supported on the jig so that surrounding parts such as the worm wheel and shaft can be accurately assembled.

<Jig>

Figure 5 is an overall perspective view of the jig 100 of the present invention, and Figure 6 is a top view of the jig 100. In the drawings, the x-axis direction is referred to as the front-to-back direction or longitudinal direction, and the y-axis direction is referred to as the left-right direction or width direction.

In Figure 5, in order to explain the structure of the jig 100, the lifter housing 2 and the guide bracket 3 are shown mounted on the jig 100.

Referring to the two drawings together, the jig 100 of the present invention is supported by a base 102, which is a square-shaped plate at the bottom, and the parts are mounted on the base 102.

A pair of linear rails 104 extending longitudinally are installed on both sides of the base 102. An intermediate plate 106 made of a square-shaped plate smaller than the base 102 is installed on the linear rail 104. By driving an actuator (not shown), the intermediate plate 106 can slide along the linear rail 14 in the forward and backward directions.

Support parts 108 are installed at four locations of the intermediate plate 106 to support the load of the mounted member in a balanced manner, and on the support part 108, a “井” shaped upper plate with a square-shaped slot drilled in the center ( 110) is installed. The upper plate 110 is a member to maintain the distance and plane between the guide brackets 3 of the lifter housing 2 until assembly is completed, and maintains the same condition as the CVVD device 1 is mounted on the engine of a car. It plays a role in maintaining and assembling.

A narrow extension portion 110a is formed forward and backward from each of the four corners around the slot of the upper plate 110, and the lifter housing center is located between the spaces formed by the two extension portions 110a facing each other in the width direction. A portion of the fixing unit 114 is mounted.

Adjacent to the extension portion 110a of the upper plate 110, a pair of boss portions 112 with their lower surfaces mounted on the middle plate 106 are installed upright. A fastening member 118, such as a bolt, is installed through the opening of each boss portion 112, and the fastening member 118 is coupled to the inside of a thread hole (not shown) of the lifter housing center fixing unit 114. Thus, the pair of lifter housing center fixing units 114 are suspended and firmly supported by the boss portion 112. The lifter housing center fixing unit 114 is a member for aligning both lifter housings 2 on the same axis, and has the function of being assembled while maintaining the same conditions as when the camshaft of an automobile is assembled to the lifter housing 2. do.

The lifter housing center fixing unit 114 includes a relatively tall circular column-shaped bar 114a, and the outer surface of the bar 114a has a needle bearing 20 press-fitted into the opening of the lifter housing 2, and has an inner diameter of It must be supported firmly from within without shaking. At this time, since there may be a difference in the inner diameter of the assembled needle bearing 20, it is desirable to form a taper on the outer surface of the bar to accommodate the needle bearing 20 regardless of the difference in inner diameter.

The lifter housing center fixing unit 114 does not directly contact the upper plate 110. The space provided by the extension portions 110a of the upper plate 110 contains the lifter housing 2, particularly a portion of the guide bracket 3 that accommodates it (see right side of FIG. 5).

Therefore, in order to keep the position of the lifter housing (2) stable and prevent it from rotating during work, an “L” shaped seating block (120) is mounted on the upper part adjacent to the slot of the upper plate (110) when viewed from the side. (120) supports at least the lower surface and the front or rear of the guide bracket (3) to prevent shaking during the assembly process.

In addition, the jig 100 of the present invention has two ball plungers 122 mounted on each of the four extension parts 110a in the longitudinal direction. “Ball plunger” is a part that is used to maintain the correct position of a member by mounting a ball on a spring and varying the height of the ball depending on the height of the member mounted on the ball. In the present invention, the ball plunger 122 allows the height of the ball to be adjusted fluidly even if the lifter housing 2 moves up and down slightly during the process of inserting the tapered bar 114a into the needle bearing inner diameter of the lifter housing 2. This functions to smoothly assemble the lifter housing (2).

Although the preferred embodiment of the jig 1 of the present invention has been described above, this is for illustrative purposes only, and various changes can be made to the jig 100 of the present invention at the level of those skilled in the art. In particular, the shape, size and number of each member do not limit the scope of the present invention.

In the manufacturing process of the CVVD device (1), the jig (1) of the present invention firmly supports the lifter housing (2) and the guide bracket (3) at the first stage, but is automatically transferred to the next process as the process progresses. It functions as a stable platform that continues to support the lifter housing 2 and its related assemblies even during the assembly process of the sliding shaft 4 and the guide shaft 6.

The assembly process of the sliding shaft 4 of the present invention is disclosed in detail in Patent Application No. 10-2021-0094330 (“Method of assembling a sliding shaft during CVVD manufacturing process”) filed on July 19, 2021. In addition, the assembly process of the guide shaft 6 is disclosed in detail in Patent Application No. 10-2021-0094329 (“Guide shaft assembly method during CVVD manufacturing process”) filed on July 19, 2021.

FIG. 7 shows that the assembly of the lifter housing 2 of FIG. 4F that has undergone the above process is mounted on the jig 100 of the present invention described above. The lifter housing (2) assembly mounted in this way is finally separated from the jig (100) and mounted on the camshaft of the automobile engine as the CVVD device (1), and the jig (100) completes the cycle function of the manufacturing process.

Above, preferred embodiments of the present invention have been described with reference to the accompanying drawings, but the present invention is not limited to the embodiments and various modifications are possible. It is obvious that the scope of rights of the present invention extends to matters that are the same or equivalent to the claims described below.

Claims (4)

A jig for supporting and moving the lifter housing assembly of a CVVD (Continuous variable valve duration) device of an automobile, the jig
Base;
An intermediate plate mounted on the base;
An upper plate installed on the middle plate to maintain the distance and plane of the lifter housing assembly until assembly is completed;
A pair of bosses mounted on the sides of the top plate; and
It is supported by the boss and includes a lifter housing center fixing unit that accommodates the lifter housing assembly,
The lifter housing center fixing unit includes a bar, and the outer surface of the bar is tapered to accommodate a needle bearing press-fitted into the opening of the lifter housing,
The upper plate has a slot drilled in the center, and extensions are formed from each corner around the slot. A seating block is installed on the upper part adjacent to the slot of the upper plate to keep the position of the lifter housing stable and prevent it from rotating during work. , now. delete delete According to clause 1,
A jig in which a ball plunger is mounted on each of the extension parts so that the height of the ball can be flexibly adjusted when the lifter housing is moved.