JPS60211018A - Remelting apparatus of shaft member - Google Patents

Abstract

PURPOSE:To provide the titled rationalized apparatus for preventing the generation of cracks and pores at the remelted part due to chill-hardening by rotating and preheating a cam shaft uniformly in an upper side-opened semilunar high- frequency coil, and remelting and hardening the surface of the cam. CONSTITUTION:A cam shaft 50 is supported by pivots 5 and 6 in an upper side- opened semilunar high-frequency coil 9, rotated 7, and uniformly preheated. Then the cam shaft is pivoted on a proximity rotating mechanism 11 by a chuck 10 with a chuck 51 and a pivot 13, and the specified parts of the cam surface 53 are successively remelted, added with metal and hardened by a torch 22. The generation of cracks due to chill-hardening and the generation of pores due to solidification resulting from insufficient venting at the treated part is prevented by the preheating of the cam shaft 50, and the remelting and hardening treatment are carried out with the compact apparatus, in good yield, with high efficiency, and at low cost.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a remelting treatment device for hardening the outer surface of a cam profile of a camshaft.

(Background Art) Remelting treatment (remelt treatment) has been put into practical use as a surface hardening treatment for the cam profile of a camshaft. As described above, in the remelting process, the surface of the cam part is melted using a plasma torch, a TIG torch, or a laser beam, and at the same time, metal powder is added to the plasma arc to form a highly hard alloy layer.

When performing the above remelt treatment, the entire camshaft is generally preheated to about 250°C to 450°C.The reason for this is that if you try to efficiently remelt and chill harden without preheating, When the cast iron rapidly cools, solidifies, and chill hardens, it causes volumetric contraction, causing cracks, and the oxygen separated from the oxide in the cast iron combines with carbon to generate GO2 gas, and before the gas can escape, GO2 gas is generated. This is because porosity occurs due to solidification, a so-called cold shut phenomenon. In the case of remelt/chill curing without preheating, the above disadvantages can be avoided by applying energy equivalent to preheating to each cam in advance, that is, performing remelt treatment by heating slowly.
This method has disadvantages in that it takes time and productivity is low.

Conventionally, preheating for remelt treatment is done by heating the camshaft with electricity, or placing it in a furnace and heating it in an atmosphere. In either case, preheating is performed in an area separate from the remelt treatment. The current situation is that In such conventional methods, preheating takes time in the case of electrical heating, and the latter requires a separate heating furnace, which increases the amount of equipment.The common disadvantage of both methods is that after preheating, the camshaft must be transferred to a separate remelt treatment device. It is necessary to transport the product, which is disadvantageous in terms of time economy and reduces work efficiency.Also, it takes time between transport and setting in the processing equipment, and the temperature may drop, so it is necessary to increase the temperature by that amount. This is also unfavorable in terms of thermal efficiency.

In addition to the above, in the conventional remelt treatment method, each cam on the camshaft is treated individually in a separate treatment process, which is also poor in work efficiency and requires a great deal of time and effort. It is also considered disadvantageous in terms of equipment, or it is possible to install processing torches in parallel for the number of cam parts in order to treat each cam part in one process, but the pitch between the cam parts is short. Implementation is difficult because of the tendency to

(Objectives of the Invention) The present invention has been made in view of the above, and its objectives are to improve the electrical efficiency, rationalization, and labor saving of remelting processing, and to make the entire apparatus compact including the preheating process. It is an object of the present invention to provide a remelting treatment apparatus for a shaft member, which aims to shorten treatment time, improve thermal efficiency, and reduce costs.

(Structure of the Invention) In order to achieve the above object, the present invention sequentially remelts each cam portion, etc. by moving the workpiece in the axial direction, which is rotatable with at least one torch.

The gist is that a heating device such as a high-frequency heating device is integrally provided in front of the processing zone.

(Embodiments) Next, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is an explanatory front view showing an example of a specific device for carrying out the present invention, FIG. 2 is a plan view of the same, and FIG. 3 is a side view of the same.

In the figure, (1) is the device, and the preheating mechanism (0) is provided at the frontmost position on the table (3) of the base (2), and the first
If the diagram shows this, the diagram becomes complicated and difficult to understand, so this is shown in Figures 2 and 3.

The preheating mechanism (4) includes a work chuck (5) and a center (8) that support both ends of the shaft portion of a camshaft (50) provided on the left and right sides in the figure. The workpiece chuck (5) is connected to a workpiece rotation motor (7), and the center (8) is connected to an axial pressing cylinder (8), with an upwardly open space between the chuck (5) and the center (6). A high frequency heating coil (8) having a semicircular arc shape and long in the axial direction is disposed. As a result, a preheating stage is constructed at the frontmost position of the table (3). This preheating mechanism (the camshaft (50) is passed through the coil (8) of 0, the cam shirt) (50) is heated via the frame (1101) provided over the entire length of the upper half of the coil (8) in the axial direction. It can be inserted and removed in the vertical direction, and the frame (
Insert the camshaft into the coil via the cylinder unit (eot), and in the example, the coil (8) is inserted into the cylinder unit provided below.
Set it on the camshaft (50) by raising and lowering (802),
The camshaft (50) supported by the chuck (5) and center (8) is moved up and down to set and release, and the chuck (5) and center (+1) are used to release the camshaft (50). supporting both ends (51) and (52);
The camshaft (50) is rotated by the motor (7). On the other hand, the coil (8) is energized to heat the camshaft at high frequency, thereby preheating the cam shirt (50).

The preheated camshaft (50) is inserted into the coil through the notch (1301) as shown in FIG.
) and move it upward to remove it from the coil.
It is transported to the processing stage located in the back.

As described above, the preheating mechanism (4) which is a part of the device (1) before the processing mechanism performs the preheating necessary for the remelt processing.The preheating is done quickly because it is high frequency heating, and after the preheating, the camshaft is moved upward. The processing posture of the camshaft in the processing mechanism and the processing posture in the preheating mechanism (0) are in the same direction, so it is easy to transfer and can be quickly transferred. There is no change in the posture of the camshaft due to the parallel transfer to the base (
2) The distance between the preheating mechanism (4) provided above and the processing mechanism (11) to be described later is as small as possible, so that preheating can be performed in the same device as the remelt treatment, and the space can be kept to a minimum. As a result, the entire device and system can be made compact, and in addition, remelting can be performed on one side and preheating can be performed on the other side, and this process can be repeated continuously to perform efficient and quick remelting processing.

Referring to the subsequent remelting process, Fig. 6 is a schematic explanatory diagram, in which a processing mechanism (11) is provided at the back of the preheating section (0), and the processing mechanism (11) has both ends of the camshaft (50) on the left and right in front. The chuck (12) and the work rotation motor (!4) are connected to a shaft pressing cylinder (15).

At the back of the cam shirt (50) supported by the chuck (12) and center (13) is a circular support frame (1B
), and vertical frame parts (17) on the left and right sides of the support frame (18), (
113) vertically spaced guide bars (113),
(20), thereby fitting and supporting the left and right sides of the holder (21) of the plasma torch (22) for remelting treatment, and the torch (22) is connected to the guide bar (Ill), (20) in the figure. Guarantees movement in the left and right direction. The tip of the torch (22) is provided with a nozzle part (23) as shown in FIG. 7, and the nozzle part (23) has a tip (25) disposed within a hollow shield cap (24). A shield gas passage (2B) such as an inert gas is formed between the chip (25) and the shield cap (25), and a working gas passage (27) such as argon gas is formed in the center of the chip (25). is formed, and a cooling passage (28) is formed around the passage (27). An electrode (28) made of tungsten or the like is provided inside the passage (27), and a shield cap (20 with no metal powder) is provided. The introduction pipes (30), (30) are inserted and fixed in such a way that the extended line of their axis intersects the extended line of the axis of the passageway (27).The discharge by the electrode (28) of the nozzle (22) and the working gas A molten pool is formed on the outer surface of the cam part (53) of the cam shirt (50) by plasma generation, while a remelting process is performed by supplying metal powder from the pipes (30) and (30) into which no metal powder has been introduced. conduct.

A feed screw (31) is rotatably installed horizontally between the upper and lower guide bars (1θ) and (2G), and a base (32) that supports the torch holder (21) is screwed onto the screw (31). The holder (21) is configured to be movable up and down relative to the base (32). The feed screw (31) is connected via a transmission mechanism (34) to a torch moving motor (33) provided outside and at the back of one of the vertical frame portions (17), and the feed screw (31) is rotated in forward and reverse directions. Configure it to drive.

Next, to explain the method of processing the camshaft (5) according to the above, the camshaft (5) preheated by the preheating mechanism (0) will be described.
0) with the loader (10), chuck (12), center (1
3) Support both ends by facing in between. Next is the torch (22
) is moved by the rotational drive of the feed screw (31) by the motor (33), and the endmost part of the plurality of cam parts of the camshaft (50), eight cam parts (53) in the example, is moved. The torch (22) is moved downward relative to the base (32), and between the surface of the cam part (53a) and the nozzle (23) Set so that a predetermined clearance is maintained.

After the above settings, the camshaft (50) is rotated by the motor (10), and the camshaft (50) is rotated at a low speed by the reduction mechanism (35), while the torch (22) is started by the rotation of the motor (33). From the position to the cam part (53
a) is moved in the transverse axial direction, and at the same time, the nozzle (23) performs the remelting process according to the above-mentioned procedure. The cam part (5
Move it up and down along with the rotation of step 3a). On the other hand, the torch (2
(2) cam shirt) (50) is moved in the axial direction from the start position of the cam portion (53a) to its axial end position, and from the end position the motor (33) is reversely rotated to return to the start position. This reciprocating motion is controlled by the cam part (
35a) is rotated at most once, within the range of rotational angle necessary to process at least the portion of the cam portion that performs the lifting function, thereby causing the torch (22) to rotate as shown in FIG.
In this embodiment, a pulse motor or the like is used to control the melting process locus (A) for the cam profile of the motor (3).
3) also serves this purpose.

After processing the first cam portion (35a), the torch (22) is moved in the axial direction to face the next cam portion, and the processing is performed as described above, and the remaining cams are sequentially processed. This allows one device to sequentially process multiple cam parts with one torch, and even if the pitch between cam parts is small, one torch can be moved in the axial direction to sequentially process them. This allows for smooth processing without any problems. Since multiple cam parts are processed by rotating the camshaft and sequentially facing each cam part with a torch, the work can be done with one device without having to remove or attach the camshaft until the process is completed. .

In the above embodiment, the torch was reciprocated at each cam part to draw a meandering trajectory by combining with the rotation of the cam part, but the torch was moved only up and down at each cam part and the axial direction was fixed, The shaft side may be reciprocated by the axial length of the cam part, but according to this, the unit of Mos (14),
Since it is necessary to reciprocate the cylinder (15) unit, the reciprocating mechanism becomes complicated and large in size.Therefore, this embodiment in which the torch is reciprocated by forward and reverse rotation of the feed screw would be extremely advantageous.

By the way, the introduction pipe (30) and (30) provided in the nozzle (23) of the torch (22) are the powder supply device (3B).
are connected to the powder via respective pipes (37) and (37), and the powder is vibrated by a vibration device (38) to be connected to the pipes (37).
), (37), and a device (39) for checking the powder flow is interposed in the middle to ensure powder supply.
1), the vertical movement of the torch, the powder supply device (3B), the vibration device (38), the confirmation device (38), and the plasma power source (4
0) etc. control is performed by a control device (41).

In the above embodiment, one torch (22) is used, but two torches (22) may be used.

That is, a torch (122) is provided as shown in each figure.

This is moved by a feed screw driven by a motor (133) provided on the opposite side of the motor (33), that is, on the right side, and is arranged parallel to the feed screw (31). In the second torch (122), each torch processes 1/2 of the total number of cams, and each torch processes 1/2 of the camshaft, thereby reducing the processing time to 1/2.

In the embodiment, by selecting two cams having the same cam profile and arranged at the same angle and processing them in order, the same program can be used to process them, and the control system can be simplified.

In this way, by moving the two torches in parallel in the axial direction, processing time can be shortened and work efficiency can be further improved.
If two torches are used, it will be suitable for processing camshafts of multi-cylinder engines, such as those with eight or twelve cam sections.

! 184 and 5 show the second embodiment, and FIG. 1 schematically shows the remelt processing mechanism (11).

A preheating mechanism (100) provided in front of the processing mechanism (11)
The coil (109) has a circular cylindrical shape, and supports one end (52) of the camshaft (50) at the center (10B), and the other end is supported by the chuck (105).
Connect the shaft (105a) of 105) to the coil (In) +7)
The length in the axial direction is approximately equal to the length in the axial direction, and the length in the axial direction of the coil (1011) is slightly longer than the length of the camshaft (50). A holder (109a) provided at the bottom of the coil (1011)
), the camshaft (50) is movable in the direction of the chuck (105), and the camshaft (50) is supported between the chuck (105) and the center (In).
50) is subjected to high frequency heating. After heating, the coil (10111) is moved in the chuck direction as shown by the chain line (B), and the coil (1011) is housed so as to surround the shaft portion (105a) and removed from the camshaft (50).
The camshaft is transferred to the processing mechanism (1).The next camshaft is held between the empty chuck (105) and the center (1013), and the coil (1011) is moved in the axial direction to transfer the camshaft to the camshaft (50). Repeat 0 or more steps to preheat.

Such a configuration may also be adopted.

Although the embodiments have been described above, the object to be processed is not limited to a camshaft, and any object having a long shaft shape can be implemented.

(Effects of the Invention) As is clear from the above, according to the present invention, a preheating device is integrally provided in the remelt processing apparatus, and preheating and remelt processing can be performed by moving the workpiece in parallel. and the remelt device can be approached, the entire remelt processing device can be made compact while being equipped with a preheating device, and the movement of the processed material between preheating and remelt can be done easily and quickly, and the movement is quick. As a result, cooling can be prevented, the preheating temperature of the workpiece during remelting can be stabilized, and a homogeneous remelted product with excellent quality can be obtained. It is possible to shorten time and improve efficiency, and because it is possible to quickly shift to remelt processing immediately after preheating, the preheating temperature can be set without considering temperature drop, and it is also superior in terms of thermal efficiency. Since only a high frequency heating device or the like is provided adjacent to the heating device, it is extremely advantageous in terms of equipment and cost compared to the conventional method which requires heating with a separate heating device and a large-scale moving mechanism.

The present invention has many advantages as described above.

[Brief explanation of drawings]

Figure 1 is an explanatory side view of the entire device, Figure 2 is a plan view of the same,
Fig. 3 is a side view of the same, Fig. 4 is a plan view of a modified embodiment, and Fig. 5 is a plan view of the modified embodiment.
6 is an explanatory diagram of the remelting mechanism, FIG. 7 is an explanatory diagram showing an example of a torch, and FIG. 8 is an explanatory diagram of the remelting process. In the drawings, (1) is the entire device, (4) is the heating device, and (11) is the heating device.
), (109) are heating coils, (12), (13)
, (14) is a rotation support device, (22) is a torch, (31
) i (33) is a torch moving mechanism, and (50) is a processed object. Figure 7 Figure 8 Procedural amendment (self-imposed April 1985) Manabu Shiga, Commissioner of the Patent Office, Patent Application No. 59-69489 2, Title of invention Relationship to the case of remelting and hardening treatment equipment for shaft members Patent application Person name (532) Honda Motor Co., Ltd. 4, Agent 2-4-5 Azabudai, Minato-ku, Tokyo 106 Masonic 39 Mori Building 2nd floor Detailed explanation of the invention Column 7 Contents of amendment 1 The name is amended as follows: "Apparatus for remelting and hardening shaft members" 2. The claims are amended as shown in the attached sheet. 3. The specification is amended as above. (1) Page 2, No. 6 "Remelting" in line and 1st θ line
The phrase ``at the same time'' in the 13th to 15th lines is corrected to ``form a chill layer.'' (2) On page 4, line 17, "remelting" is corrected to "remelting and hardening." Attachment "2. Claim 1: A heating device for holding a workpiece having a plurality of workpieces spaced apart in the axial direction and heating the workpiece; and a heating device for heating the workpiece after heating. A device for holding the workpiece in parallel and spaced apart as shown below and rotating the workpiece, a processing torch that faces the part to be treated of the rotating workpiece and processes the outer surface of the workpiece, and the torch A remelting and hardening treatment apparatus for a shaft member, comprising a torch axial movement device for sequentially bringing the torch onto the surface of a plurality of treated parts of the workpiece. 2. The heating device is a high frequency heating device, A heating device used in the apparatus according to claim 1, wherein the heating coil has a concave cross section with an open upper part, has approximately the same length as the object to be processed, and rotates the object to be processed in the coil. 3 , The heating device is a high-frequency heating device, the heating coil is cylindrical, has approximately the same length as the object to be processed, and is movable in the axial direction.

Claims (1)

[Claims] 1. A heating device that holds a workpiece having a plurality of workpieces spaced apart in the axial direction and heats the workpiece, and a heating device that heats the workpiece after heating. A device that similarly holds the workpiece in parallel and rotates the workpiece, a processing torch that faces the processing part of the rotating workpiece and processes the outer surface of the workpiece, and a processing torch that processes the outer surface of the workpiece. A remelting treatment apparatus for a shaft member, comprising a torch axially moving device for sequentially bringing the torch onto the surfaces of a plurality of parts to be treated. 2. The heating device is a high-frequency heating device, the heating coil has a concave cross section with an open upper part, has approximately the same length as the object to be processed, and the object to be processed is rotated in the coil. A heating device used in the device of item 1. 3. The heating device used in the apparatus according to claim 1, wherein the heating device is a high-frequency heating device, the heating coil is cylindrical, has approximately the same length as the object to be processed, and is movable in the axial direction.