JPS6073167A - Method of manufacturing cam shaft - Google Patents

Abstract

PURPOSE:To diminish the number of manufacturing steps, by providing a recess on the peripheral surface of a cam shaft, providing the inside circumferential surface o the fitting hole of an assembled member with a recess in a position corresponding to that of the recess of the cam shaft, and by inserting a wire into both the recesses. CONSTITUTION:A recess 12 is provided on the peripheral surface of a cam shaft 11. Another recess 15 is provided on the inside circumferential surface of the fitting hole 14 of an assembled member 10, in a position corresponding to that of the recess 12 of the cam shaft 11. A wire 16 is inserted into both the recesses 12, 15 to secure the member 10 on the cam shaft 11. According to this constitution, the form and dimensions of the recesses 12, 15 do not need to be strictly accurate, and the member 10 is quickly assembled on the cam shaft 11. Therefore, the member 10 is easily assembled in a small number of steps.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a camshaft having a solid shaft or a hollow shaft made of steel;
Assembling parts such as cams, journals, gears, etc. that are separately manufactured are assembled on the outside of the shaft, and the assembly type is manufactured by rolling or liquid phase sintering, and how to manufacture the shaft.
): regarding.

[Prior Art] Conventionally, when joining this type of assembled old parts to a camshaft by Ro 4=J or liquid phase sintering, the row peripheral surface of the camshaft was used to position the camshaft in the circumferential direction. One or more grooves are formed in the longitudinal direction, and protrusions into which the grooves are fitted are formed at desired positions on the inner circumferential surface of the fitting hole of the assembly component, but the accuracy of positioning is limited. In order to achieve this, the shape, direction, position, etc. of the gate structure and protrusion had to be precisely manufactured, which required a large number of manufacturing units.

In addition, when this type of assembled parts are joined to the camshaft by liquid phase sintering, the length and direction of the camshafts of the old and assembled parts vary from part to part, resulting in variations in the length and direction of the camshafts. There was a drawback that the SJ methods were not aligned.

As a result of repeated research to investigate the cause of this, the inventors of the present invention have discovered that the unevenness of the assembled mowing method is due to the following causes. That is, as shown in FIGS. 1 and 2, the cam lobe lO, which is a sintered assembly part, is fitted onto the camshaft 11 and assembled, and this is placed in a sintering furnace and subjected to liquid phase sintering. and,
The cam lobe 10 is centered around the position where it first starts joining with respect to the camshaft 1.1, and this position is subject to a force of 1,
It became clear that the dimensions of the assembled parts after sintering were not the same because the legs were not on the lobes 1O4L.

For example, when the cam lobe lO is assembled to the camshaft 11, if the cam lobe lO is first joined to the camshaft 11 at point A in the figure as shown in Fig. 3, then after liquid phase sintering, the image shown in Fig. 4 If the cam lobe 10 contracts around this point A as shown by the line, and if the cam lobe 10 is first joined to the camshaft 11 at point B in FIG. 3, then after liquid phase sintering, the imaginary line in FIG. As shown, the cam lobe 10 contracts around point B. The shrinkage phenomenon described in items 1-6 is not limited to the cam lobe, but also occurs in other sintered journals, gear parts, etc. as well. Therefore, the position of the assembled parts relative to the camshaft after liquid phase sintering changes depending on the initial joining point and is not constant.

The present inventors formed a concave groove instead of a protrusion as a means for positioning the camshaft of the assembly part in the periaxial direction, and inserted a metal wire into the two gate structures. The present invention was completed by focusing on the fact that it can be made small.

In addition, as a first step in the longitudinal positioning of the camshaft of the assembled parts made by Yakimu 11, a metal wire rod with a melting point lower than the melting point of the assembled parts (= set(
-If you insert it into the two grooves as a joining starting material during liquid phase sintering of 1 part and proactively create the joining starting point for parts A and J at ``1!J'', the above drawbacks will be resolved. By paying attention to this fact, we have completed the present invention.

[Objective of the Invention] The first object of the present invention is to easily join and fold assembly parts such as cam lobes, journals, and gears at predetermined positions around the camshaft with a small number of manufacturing steps.・The purpose of the first I+ is to propose a manufacturing method for the sintered assembly parts in the longitudinal direction of the camshaft. The power that can be obtained is
The purpose of this invention is to provide a method for manufacturing the same.

[Structure of the Invention] A method for manufacturing a camshaft according to the present invention includes forming a longitudinal groove at one location on the outer circumferential surface of the camshaft, and forming a groove in the fitting hole of the assembly component to be fitted to the camshaft. A gate structure is formed on the circumferential surface of the assembly part to face the groove when the assembly part is placed at a predetermined position with respect to the camshaft, and the assembly part is connected to the cam so that both the grooves face each other. After being fitted and arranged on the shaft, a metal wire is inserted into the +I14 recess to secure the assembled parts and join them to the camshaft.

At this time, the connection of the group 4=J parts to the cam 11 is as follows:
It can be carried out by rolling or liquid phase sintering. In the case of liquid phase sintering, the assembled parts are made of sintered parts, and the metal wire is heated at a temperature lower than the liquid phase generation temperature of the assembled parts. If it is made of a metal that generates a liquid phase, the metal wire becomes the joining starting material, and there is no deviation of the position of group 4-J in the direction around @11 of the camshaft of group (=j) from the predetermined position, which is desirable.

In particular, if a convex part is formed on this low-melting point metal wire so that when the metal wire is inserted into the double-concave groove, only one convex part comes into contact with the double-concave groove, the welding starting point can be It may be arbitrarily set at a desired position.

In addition, when the assembled parts consist of multiple parts, the low melting point gold MY wire may be used as a short sword inserted into each part separately, or as a tile material that is commonly inserted into multiple parts with a diameter of 1Φ. You can also do this. If the length is long, it is necessary to form a convex portion of %71 (item 47) in accordance with the predetermined spacing of each part (= j dimension or batch). It is desirable to have all the necessary items.

[Example] Next, embodiments of the present invention will be described in detail based on the drawings.

FIGS. 6 and 7 are 11 views of the joint bending of a cam lobe and a camshaft in the method of manufacturing a camshaft according to the first embodiment of the present invention. The characteristic feature of this embodiment is that a concave groove 12 in the longitudinal direction is formed at a location l on the outer circumferential surface of the camshaft 11.
A groove 15 is formed on the inner circumferential surface of the fitting hole 14 of the cam lobe 10 to be fitted into the cam shaft 1, and a groove 15 is formed to face the groove 12 when the cam lobe 10 is placed at a predetermined position with respect to the camshaft 11. After fitting and arranging the cam lobe IO on the camshaft 11 so that the grooves 12.15 face each other, the metal wire 16 is inserted into both grooves 12.15 to fix the cam lobe 10, and the camshaft 1
It is at the point where it joins 1.

Here, the cross-sectional shape of each of the grooves 12 and 15 may be a rectangular combination as shown in FIG. 8 or a triangular combination as shown in FIG. 9. Moreover, the cross-sectional shape of the metal wire 16 is
As long as the shape is in contact with both grooves 12 and I5 at the same time, it may be a square corresponding to the two grooves 12.15 (Fig. 8), or a circular shape dissimilar to the shape of the groove 12.15 (Fig. 9). ).

The cam lobe lO having such a configuration and the camshaft 11 are joined by brazing or liquid phase sintering.

According to Loi j, the cam lobe 10 is Loi = l-
If liquid phase sintering is used, the cam lower IO is made of a sintered member.

This manufacturing method does not require the shape of the groove 12.15, =J method, etc. to be manufactured with strict precision as in the case of conventional protrusions and grooves.Moreover, the cam lobe lO is controlled by a force of 1, and the shaft 11 by L+r. After fitting to a predetermined position l in the ~ direction, the groove 15 is inserted into the groove 12.
Simply insert the metal wire 16 into the double concave groove facing the
Assembling of the force L/lob 10 can be performed quickly.

FIG. 10 is a longitudinal sectional view of a cam lobe and a camshaft joined together in a method of manufacturing a camshaft according to a second embodiment of the present invention. The characteristic feature of this embodiment is that the cam lobe 10 and the camshaft 11 are joined by liquid phase sintering, and one of the metal wires 16 is heated to a liquid phase temperature of 1111 days, which is lower than the liquid phase generation temperature of the cam lobe 10. The metal that produces it, for example copper or? 11 alloy, aluminum or aluminum alloy, lead or lead alloy, tin or tin alloy, bismuth or bismuth alloy, antimony or antimony alloy, zinc or zinc alloy A), and furthermore, the metal wire 16 is
In this example, it is formed into a short piece with a convex portion 17 at the end. Note that this convex portion 17 is formed in the fitting hole 14 when the metal wire 16 is inserted into both 1111 grooves 12.15.
It is located in the middle of the groove and is formed in a J-shape so that only the convex portion 17 contacts both grooves.

The cam lobe lO having such a configuration is fitted onto the camshaft 11,
With the center position of the cam lobe lO aligned with the predetermined position of the force axis 11, one end of the fitting hole 14 (in this example, the left end)
If liquid phase sintering is performed after inserting the metal wire 16 into the double concave grooves 12.15, the metal wire 1 with a low melting point will be
Since the convex portion 17 of 6 melts, the cam lobe 10 contracts with respect to the center position of the fitting hole 12. As a result, the assembly position of the cam lobe lO does not change at all times, and when a plurality of cam lobes 10 are assembled to the camshaft 11, the assembly position of each cam lobe l□=J method becomes equal.

Note that if a convex portion 18 is also provided at the right end of the metal wire 16 as shown in FIG. 11, the convex portion 18 will act as a stopper for the metal wire 16 inserted into the groove 12. Can be determined accurately.

FIG. 12 is a longitudinal sectional view of a cam lobe and a camshaft joined together in a method for manufacturing a camshaft according to a third embodiment of the present invention. The characteristic feature of this embodiment is that the metal wire 1 shown in the second embodiment
6 as a long material that is commonly inserted into multiple cam lobes 1O,
The convex portion 19 is formed for each cam lobe in accordance with the predetermined mounting interval of each cam lobe 1O.

The plurality of forces 1 and lobes 10 configured as described above are fitted to the camshaft 11, and with the center position of the cam lobe 10 aligned with a predetermined position of the camshaft 11, a double concave groove is inserted from one end of the fitting hole 14. 1
2. After inserting the metal wire 16 into the hole 15 and setting one end of the long wire as a reference so that each convex portion 19 is located at the center of the fitting hole 14, liquid phase annealing is carried out in the second implementation. As in the example, the cam lobe lO contracts with respect to the center position of the fitting hole 14, and the assembly directions ζJ' of a plurality of cam lobes can be aligned all at once.

In addition, in Example 1, a cam lobe is shown as an example of a sintered assembly part, but other sintered parts such as journals and gears can also be used.
(=One part can also be reproduced in the same way.

In addition, in the first and third embodiments, a set of cam lobes (=JJll
The reference position of the cam lobe is set as the center position of the cam lobe, and the protrusions l17 and 19 are both arranged at the center position of the fitting hole 14. If so, it is not limited to the above example, and may be each end of the cam lobe and the fitting hole.

[Effects of the Invention] As described above, according to the present invention, a concave groove is formed on the outer circumferential surface of the cam@11, and the groove is formed on the inner circumferential surface of the fitting hole of the assembly parts such as the cam lobe, journal, gear, etc. By forming grooves at predetermined positions,
After fitting and arranging the assembly parts on the camshaft so that these grooves face each other, metal wires are inserted into both grooves, and the assembly (=J parts is fixed to the camshaft). , the shape of the double-concave groove, the -J- method, etc., do not need to be manufactured with strict precision like conventional protrusions and gate structures, and moreover, it is not necessary to manufacture the parts to be assembled to a predetermined position in the longitudinal direction of the camshaft. By simply placing the double grooves facing each other and inserting a metal wire into the grooves, you can quickly assemble the assembled parts. It can be joined at a predetermined position around the axis.

In particular, when joining the assembled parts to the camshaft by liquid-phase sintering, the assembled parts are made of sintered material, and the metal wire in 1- is set at a temperature lower than the liquid phase generation temperature of the group 4=1 part. If it is made of a metal that forms a liquid phase at certain temperatures.

The metal wire serves as a welding starting material, and the assembly position of the assembly component in the axial direction of the camshaft can be matched with a predetermined position with extremely high accuracy.

Additionally, convex portions are formed on this low melting point metal wire.

When this metal wire is inserted into the double concave groove, 1
If only the two convex parts are brought into contact at predetermined positions, the assembly part will contract in a certain direction based on the convex part, so the M1 distance and J direction in the longitudinal direction of the camshaft of the assembly part will be It does not always change and can be made uniform without causing variations between the shafts.

Furthermore, when the assembled parts consist of multiple parts, the metal wire with a low melting point can be cut into short pieces, and each part can be inserted and positioned separately, and the metal wire can be made into long pieces. In addition, if protrusions are formed on the long material for each part in accordance with the predetermined spacing of each part and communicated with the plurality of parts, the assembly dimension in the longitudinal direction of the camshaft of one part of the plurality of assemblies can be adjusted. can be prepared all at once, reducing the number of man-hours required for assembly.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal cross-sectional view of the assembled camshaft, Fig. 2 is an enlarged cross-sectional view taken along I-I in Fig. 1, and Fig. 3 is a cam lobe before liquid phase sintering in the conventional camshaft manufacturing method. Figures 4 and 5 are vertical cross-sectional views of the cam lobe and force 1 shaft before and after sintering in Figure 3, and ft56 is a joint longitudinal cross-sectional view of the force 1 shaft of the first embodiment of the present invention.・A vertical cross-sectional view of the cam lobe and cam shaft in the manufacturing method, FIG. 7 is II of FIG. 6.
-II sectional view, FIGS. 8 and 9 are cross-sectional views of the grooves formed in the cam lobe and the camshaft, and the metal wire inserted into these grooves, and FIGS. 10 and 11 are cross-sectional views of the present invention. FIG. 12 is a vertical cross-sectional view of a cam lobe and a camshaft joined together in a method of manufacturing a camshaft according to a second embodiment of the present invention. FIG. lO: cam lobe, ll: cam shaft, 12, 15: groove, 14: fitting hole, 16 bimetallic wire, 17, 18, 19: convex portion.

Claims (1)

[Scope of Claims] (1) A concave groove in the longitudinal direction is formed at one position on the outer circumferential surface of the camshaft, and the inner circumferential surface of the fitting hole of the assembly part to be fitted to the camshaft is formed in the longitudinal direction. When the assembled parts described in 11j are placed in a predetermined position with respect to the camshaft, a concave groove is formed opposite to the concave groove described in ii, and both of the concave grooves are formed. "111 M
After aligning the IKiba product to the camshaft in 7iij and placing it 6, insert a metal wire into the both gates in l1ij to fix the assembly r'sR product and join it to the cam Tsukuda 1. camshaft manufacturing method. (2) The joining of the six cams +11+ with a set depth of 1" is done by brazing 71.
A of Kam Nyahu I. listed in , 1 person. t3) The assembly part is a sintered member, and the joining of this assembly part to the camshaft is done by liquid phase sintering! l
Cam shirt I as described in Claims 1 'J4 of the 11th revision.
manufacturing method. (4) The method for manufacturing a camshaft according to claim 3, wherein the metal wire is made of a metal that generates a liquid phase at a temperature lower than the liquid phase generation temperature of the assembled parts. (5) A convex portion is formed on the metal wire, and when the metal wire is inserted into the double concave groove, only one convex portion contacts the double concave groove. The method for manufacturing a camshaft according to item 4. (6) The assembly part is made up of a plurality of parts, and the metal wire is a short piece inserted separately for each part. (7) The M1 I+J part consists of multiple parts, and the metal wire is a long material that is commonly inserted into several parts.
A convex portion is formed for each part in accordance with a predetermined reprint interval of JFJ products.
The force described in l, the method of manufacturing the shaft v;.