Positioning fixture for cylinder heads in machining centers

Abstract

A cylinder head positioning fixture specifically designed for machining centers is disclosed. This tool mainly consists of a positioning fixture base, a main positioning threaded pin, an auxiliary positioning threaded pin, a center positioning pin, specially designed connecting bolts, and a non-standard pressure plate. This cylinder head positioning fixture is easy to assemble and disassemble, convenient to position, and can be reused after a single setup. It reduces the workload of operators, minimizes the impact of human factors during part clamping, and improves repeatability and stability while saving significant time. This increases work efficiency and greatly reduces quality problems caused by part position deviations due to unstable temporary fixtures. This invention offers the advantages of simple operation and precise positioning.

Description

Technical Field

[0001] This invention relates to machining centers, and in particular to a positioning fixture for cylinder heads in machining centers. Background Technology

[0002] Figure 1 The worktable is a common feature of machining centers, with only five horizontal T-slots and two locating pin holes. Figure 2 This is a structural schematic diagram of a cylinder head to be machined. Its shape is complex, and the machining process involves numerous, many of which are oblique or deep holes. When the part is large or irregularly shaped, simply using the existing worktable to fix the part is not only difficult to assemble, but also prone to instability due to the limited availability of T-slots. Furthermore, due to the complex shape and numerous machining steps of the cylinder head, the time spent on each process for onboard adjustment and zero-position setting is very long, and the pressure plate position needs to be changed during machining, requiring a certain level of technical skill from the operators.

[0003] There is an urgent need to design a positioning fixture for cylinder heads in machining centers to standardize the positioning datum. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of existing worktables commonly used in machining centers and to provide a positioning fixture for cylinder heads in machining centers. This positioning fixture achieves stable clamping of parts, solving the problem of difficulty in assembling parts with unusual shapes when machining centers. This positioning fixture reduces the workload of operators, minimizes the impact of human factors during part clamping, and improves repeatability and stability while saving significant time. It increases work efficiency and greatly reduces quality problems caused by part position deviations due to unstable temporary fixtures. This positioning fixture has the advantages of simple operation and accurate positioning.

[0005] The technical solution of the present invention is as follows:

[0006] A cylinder head positioning fixture for a machining center is characterized by including a positioning fixture base, a main positioning threaded pin, an auxiliary positioning threaded pin, a characteristic connecting bolt, a center positioning pin, and a non-standard pressure plate.

[0007] The positioning fixture base is square in shape, with a central positioning pin hole at its center. Two main positioning threaded pins and two auxiliary positioning threaded pins are respectively provided at the four corners of the positioning fixture base to mate with the structure of the cylinder head to be processed. The main positioning threaded pins are divided into upper and lower parts, separated by a runout groove. The lower part connects to the positioning fixture base and is fixed with five connecting bolts, while the upper part is used for precise positioning of the part. It has a central threaded through hole for fixing a special connecting bolt. The main positioning threaded pins are placed diagonally on the positioning fixture base. Similarly, the auxiliary positioning threaded pins are also divided into upper and lower parts, separated by a runout groove. The lower part connects to the positioning fixture base and is fixed with five connecting bolts. The upper part not only uses a clearance fit with the part but also features a flattened design in several places to prevent over-positioning between the part and the positioning fixture. It is used to assist in positioning the part and has a central threaded through hole for fixing a special connecting bolt. The auxiliary positioning threaded pins are placed diagonally on the positioning fixture base.

[0008] The specially designed connecting bolts fix the parts to the positioning fixture by matching the process bolt holes and non-standard pressure plates on the parts. The hexagonal part of the bolt is recessed into the process hole to prevent interference during processing.

[0009] The central locating pin is used to position this fixture on the machine tool's worktable. The locating pin has a threaded through hole in its center for easy removal.

[0010] Technical advantages of the present invention:

[0011] This invention is specifically designed for cylinder head positioning in machining centers. A positioning plate is installed on the machining center's worktable, secured by a central positioning pin and several through holes. The part is then positioned using threaded positioning pins and secured with connecting bolts and a non-standard pressure plate. After debugging, the entire assembly can be removed from the machine, and when used again for the same part at the same workstation, it is not necessary to readjust the zero position. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the machining center's worktable.

[0013] Figure 2 Schematic diagram of the cylinder head to be processed

[0014] Figure 3 This is a schematic diagram of the cylinder head positioning fixture for machining centers according to the present invention.

[0015] Figure 4 This is a diagram showing the use of the cylinder head positioning fixture of the present invention in a machining center.

[0016] In the diagram: 1—Positioning fixture base; 2—Main positioning threaded pin; 3—Auxiliary positioning threaded pin; 4—Special connecting bolt; 5—Center positioning pin; 6—Non-standard pressure plate. Detailed Implementation

[0017] The cylinder head positioning fixture of the present invention, specifically for machining centers, will be further described below with reference to the accompanying drawings and specific embodiments, but this should not be construed as limiting the scope of protection of the present invention.

[0018] For an example, please refer to [link / reference]. Figure 3 As shown in the figure, the cylinder head positioning fixture of the present invention for machining centers includes a positioning fixture base 1, a main positioning threaded pin 2, an auxiliary positioning threaded pin 3, a feature connecting bolt 4, a center positioning pin 5, and a non-standard pressure plate 6.

[0019] The positioning fixture base 1 is rectangular. A central positioning pin hole 5 is located at the center of the positioning fixture base 1. Two main positioning threaded pins 2 and two auxiliary positioning threaded pins 3 are respectively provided at the four corners of the positioning fixture base 1 to mate with the structure of the cylinder head to be processed. The main positioning threaded pins 2 are divided into upper and lower parts, separated by a runout groove. The lower part connects to the positioning fixture base 1 and is fixed with five connecting bolts. The upper part is used for precise positioning of the part and has a threaded through hole in the center for fixing a special connecting bolt 4. The main positioning threaded pins 2 are placed diagonally on the positioning fixture base 1. The auxiliary positioning threaded pins 3 are also divided into upper and lower parts, separated by a runout groove. The lower part connects to the positioning fixture base 1 and is fixed with five connecting bolts. The upper part not only uses a clearance fit with the part but also has multiple flattened designs to prevent over-positioning between the part and the positioning fixture. It is used to assist in positioning the part and has a threaded through hole in the center for fixing a special connecting bolt 4. The auxiliary positioning threaded pins 3 are placed diagonally on the positioning fixture base 1.

[0020] The specially designed connecting bolt 4, through the process bolt hole on the part and the non-standard pressure plate 6, fixes the part on the positioning fixture. The hexagonal part of the bolt is recessed into the process hole to prevent interference during processing.

[0021] The center positioning pin 5 is used to position this tooling on the machine tool's worktable. The center of the positioning pin 5 has a threaded through hole for easy removal.

[0022] A preferred embodiment of the present invention is the positioning and clamping of a self-developed medium-speed diesel engine cylinder head part during machining. For example... Figure 4 As shown.

[0023] Experiments show that using the existing worktable of the machining center is not only extremely difficult, but also prone to interference due to the large size of the parts and the generally long machining tools. The cylinder head positioning fixture of this invention, specifically designed for machining centers, reduces the workload of operators and minimizes the impact of human factors during part clamping. It saves significant time while improving repeatability and stability, increasing work efficiency and greatly reducing quality problems caused by part positional deviations due to unstable temporary fixtures. This positioning fixture is easy to operate and provides precise positioning. It is not only accurate, convenient, and stable in positioning, but also prevents interference during machining.

[0024] Using this invention can ensure the proper positioning of parts during clamping, and can guarantee the stability and positioning accuracy of clamping.

Claims

1. A cylinder head positioning fixture for a machining center, characterized in that... It includes a positioning fixture base (1), a main positioning threaded pin (2), an auxiliary positioning threaded pin (3), a special connecting bolt (4), a center positioning pin (5), and a non-standard pressure plate (6). The positioning fixture base (1) is square in shape. A central positioning pin hole (5) is provided in the center of the positioning fixture base (1). Two main positioning threaded pins (2) and two auxiliary positioning threaded pins (3) are respectively provided at the four corners of the positioning fixture base (1) to cooperate with the structure of the cylinder head to be processed. The main positioning threaded pin (2) is divided into upper and lower parts, which are separated by a runout groove. The lower part is connected to the positioning fixture base (1) and fixed with five connecting bolts. The upper part is used for precise positioning of the parts. There is a threaded through hole in the center for fixing a special connecting bolt (4). The main positioning threaded pin (2) is placed diagonally on the positioning fixture base (1); the auxiliary positioning threaded pin (3) is divided into upper and lower parts, separated by a runout groove in the middle. The lower part is connected to the positioning fixture base (1) and fixed with five connecting bolts. The upper part not only has a clearance fit with the part, but also has a flat design in many places to prevent over-positioning between the part and the positioning fixture. It is used to assist in positioning the part. There is a threaded through hole in the center for fixing a special connecting bolt (4). The auxiliary positioning threaded pin (3) is placed diagonally on the positioning fixture base (1). The specially designed connecting bolt (4) fixes the part on the positioning fixture by matching the process bolt hole on the part and the non-standard pressure plate (6). The hexagonal part of the bolt is submerged in the process hole to prevent interference during processing. The center positioning pin (5) is used to position the fixture on the machine tool worktable. The center of the positioning pin (5) has a threaded through hole for easy removal.

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