JPS6364498B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a hardening device for leaf springs. When manufacturing arcuate leaf springs for use in vehicle suspension systems and the like, a hardening device is used to cool the arcuately formed high-temperature leaf spring material by immersing it in oil. In this case, if the leaf spring material is immersed in oil in a free state, quenching distortion will occur and straightening work will be required.
A means for holding the leaf spring material in a predetermined shape and hardening it is used. In this type of conventional device, as illustrated in FIGS. 1 and 2, an octagonal wheel 2 is rotatably driven with its lower part immersed in quenching oil 1;
A supporting member 4 in the holding mechanism 3 is provided on each side of the octagonal ring 2.
The plate spring material a is held between the push pieces 5 and a plurality of push pieces 5 facing each other so as to be able to freely move toward and away from each other. Therefore, since the number of holding mechanisms 2 used for cooling in the quenching oil 1 is only about 5, the usage efficiency is low and the tact time is inevitably slow, resulting in poor productivity. This tendency becomes more pronounced as the thickness of the leaf spring material a increases. In addition, when hardening leaf spring materials of different shapes, all holding mechanisms 3
Since it is necessary to replace the support member 4 and adjust the push pieces 5, it takes a lot of time for setup work.
Moreover, when the leaf spring material a is transferred from the quenching oil 1 to the atmosphere at the completion of quenching as the octagonal ring 2 rotates, the leaf spring material a is still at a fairly high temperature, so it generates a large amount of oil smoke, and the holding mechanism Since oil smoke is also generated from the 3rd class, it is necessary to install a large oil smoke removal device with a complicated structure. Furthermore, as shown in FIG. 3, in the above-described hardening apparatus 6, transverse conveyors 9, 9 are provided between the heating furnace 7 and the tempering furnace 8 to transport the leaf spring material a. However, there were problems such as the need for a large amount of space. The present invention has been made under the above circumstances, and its objectives are to provide a simple structure, requiring less space, excellent production efficiency, simple and easy setup work, and moreover, to reduce the amount of oil smoke. It is an object of the present invention to provide a hardening device for leaf springs that generates a small amount of heat generated. Hereinafter, the present invention will be described with reference to an illustrated embodiment. In FIG. 4, a heating furnace 10 includes a first transfer device 11 provided within the furnace. As shown in FIG. 5, this transfer device 11 is equipped with a fixed beam 12 and a movable beam 13.
The plate spring material a being heated is sequentially transferred by moving up and down and back and forth in a rectangular trajectory 14. Note that the fixed beam 12 and the movable beam 13 each have a sawtooth upper surface so as to be able to hold the leaf spring material a in a predetermined position. The leaf spring material a heated to a predetermined temperature is transferred to the next stage via the second transfer device 15. This second transfer device 15 includes a take-out beam 16 that can freely move in and out of the heating furnace 10, a take-out conveyor 17 that transports the leaf spring material a taken out from the heating furnace 10 by the beam 16, and It includes an insertion chute 18 provided on the exit side, and further includes an insertion mechanism 20. As illustrated in FIG. 6, the insertion mechanism 20 includes a link 21 whose upper end is swingable in the front-rear direction, and a base end rotatably connected to the upper end of the link 21 so as to be able to reciprocate in the front-rear direction. Insertion beam 22 and link 2
1 and the insertion beam 2
2, and an insertion member 25 that can be raised and lowered. In addition, the insertion beam 22 includes a plurality of (three in the figure) support portions 2 arranged at intervals in the front-rear direction.
6... is provided. In the illustrated example, an insertion stage A, a drilling stage B, and a forming stage C are arranged in this order facing the movement path of the insertion beam 22. Then, the leaf spring material a is inserted into the chute 18.
When the link 21 is transported to the insertion stage A by the cylinder device 23, it is returned to the initial position shown by the solid line in the figure, and when the insertion chute 18 is lowered, the leaf spring material _a1 is moved to the first support part 26. Supported. Next, when the link 21 is moved to the forward position shown by the chain line, the first support part 26 is moved to the perforation stage B, and the insertion beam 22 is lowered by the cylinder device 24, so that the leaf spring material _a1 is It is transferred to the perforation device 30. When the link 21 is returned to the initial position again, the second leaf spring material a ₂ (not shown) is supported on the first support portion 26 in the same manner as described above, and the first leaf spring material a 2 (not shown) is supported by the first support portion 26 as described above. The leaf spring material a ₁ is supported by the second support portion 26 as the insertion beam 22 rises. When the link 21 is moved to the forward position again, the first leaf spring material _a1 is transferred to the forming device 35, which will be described later, at the forming stage C, and the second leaf spring material _a2 is transferred to the drilling device 30. be done. When the link 21 is swung once more, the third leaf spring material _a3 supported by the first support part 26
(not shown) is transferred to the drilling stage B, the second leaf spring material _a2 is transferred to the forming stage C, and the first leaf spring material _a1 is inserted into the cylinder device 24 with the insertion beam 22. The insertion member 25 is moved to the insertion member 25 by being tilted forward and downward. Thereafter, the leaf spring materials a are similarly transported from the heating furnace 10 to the insertion member 25 through the perforating device 30 and the forming device 35 in this order. As illustrated in FIGS. 7 and 8, the perforating device 30 includes a longitudinal positioning means 31 for holding the leaf spring material a in the width direction, and a lateral positioning means 32 for holding the plate spring material in the longitudinal direction. It also includes a punch 33 and a die 34 located on both sides of the leaf spring material a in the thickness direction and facing the center thereof. Then, punch 3 against the leaf spring material a.
3 and die 34 to form a center hole. The molding device 35 is equipped with an upper mold 36 and a lower mold 37 that face both surfaces of the leaf spring material a in the thickness direction so as to be able to move toward and away from them. Upper mold 36
The edge 39 facing the pusher pieces 38 is formed into an arc shape that is substantially equal to the envelope. The lower mold 37 has a plurality of pressing pieces 38 arranged at intervals in the longitudinal direction.
It is equipped with The push pieces 38 are supported so that the envelope of the tip can be variably set to a desired arc shape. Then, press the leaf spring material a onto the push pieces 38... and the edge 39.
The structure is such that it can be formed into a predetermined arc shape by being held between the two. The quenching tank 40 houses quenching oil 41 therein as shown in FIGS. 10 and 11, and
A third transfer device 42 immersed in quenching liquid 41 is provided. This transfer device 42 has a conveyor 43. The conveyor 43 has a plurality of blocks 44 arranged at predetermined pitches along its entire length.
(some of which are not shown), each of these blocks 44
. . . One leaf spring material a is held for each spring, and each time it is moved one pitch in the direction of arrow A, it is stopped for a predetermined period of time, so that it is intermittently moved. The quenching tank 40 is provided with cooling pipes 45 located on both sides of the conveyor 43. These pipes 45 have a large number of small holes 46 facing the movement path of the leaf spring material a and through which the quenching liquid 41 is injected.
, and is configured to cool and stir the quenching liquid in the vicinity of the leaf spring material a. The quenching tank 40 is provided with a holding device 50 capable of holding the leaf spring material a in a predetermined shape. This device 50 includes an upper mold part 51 and a lower mold part 52. The upper mold part 51 includes a base part 53 and a plurality of parts (5 in the figure) which are removably attached to the base part 53 and extend laterally.
In one case), the plate-like body 54 is provided. These plate-like bodies 54 are the blocks 4 of the conveyor 43.
4... are arranged at equal pitches, and the quenching liquid 4
1 and has an arcuate lower edge 55 whose lateral center portion bulges downward. Further, the lower mold part 52 has a central pedestal 56 disposed at the center in the horizontal direction.
and a pair of side pedestals 5 placed on both sides of this.
A central frame body 58 is attached to a central pedestal 56 which is provided with 7 and 57. Side pedestals 57, 57
side frames 60, 60 via pins 59, 59.
is supported so as to be swingable laterally. Each of these frames 58 and 60, 60 has a guide block 6.
1... are supported so that they can be raised and lowered, and
A cylinder device 62 for driving each guide block 61 up and down is provided, respectively. Each guide block 61 supports a pusher piece 63 which is positioned opposite to the plate-shaped body 54 and can be raised and lowered, and a leaf spring member 64 which biases each pusher piece 63 upward. is provided. The holding device 50 is configured to hold the leaf spring material a in a predetermined shape by sandwiching the leaf spring material a between the push pieces 63 and the plate-shaped body 54 when the guide blocks 61 are in the raised position. Further, the frames 60, 60 arranged on both sides are connected to a cylinder device 67 via a link mechanism 66 including a link 65 that penetrates the quenching tank 40 in a fluid-tight and reciprocating manner. By adjusting the amount of expansion and contraction of the cylinder device 67, the lateral positions of the push pieces 63 can be variably set, so that it can be adapted to various leaf spring materials having different lengths. In the quenching tank 40, the leaf spring material a, which has been heated to a predetermined temperature in the heating furnace 10 and has undergone forming processes such as drilling and bending, is transferred into the quenching tank 40 via the insertion member 25. Then, the insertion member 25 is lowered and moved thereto when the conveyor 43 stops transferring, and is intermittently moved by the conveyor 43 as described above. and,
When passing through the holding device 50, the plate-shaped body 54
Each time the push piece 63... and the push piece 63... stop at a mutually opposing portion, the push piece 63...
By raising the plate spring material a, the plate-shaped body 5
The plate-shaped body 54 is held between the press pieces 63 and 4...
... is held in a predetermined arc shape formed on the lower edge 55. The longitudinal position of the holding device 20 with respect to the conveyor 43 is set so that the leaf spring material a is held in a predetermined shape only while it is in and near the transformation region from austenite to martensite. Further, the conveyor 43 has a length sufficient to substantially completely cool the leaf spring material a. A fourth transfer device 7 is provided on the downstream side of the quenching tank 40.
0 is set. This transfer device 70
As illustrated in FIG. 2, a pulling member 71 located on the downstream side of the conveyor 43 and driven up and down, and a quenching tank 4
The first arm 72 is located above 0 and can be raised and lowered freely.
and a second arm rotatably connected to the first arm.
The lifting member 71 includes an arm 73 and a chuck portion 74 provided at the tip of the second arm 73.
The leaf spring material a pulled up from the conveyor 43 by
It is configured such that it can be held by a chuck portion 74 and transferred to a tempering furnace 75. The first transfer device 11, the second transfer device 1
5. Third transfer device 42 and fourth transfer device 7
0 is the holding device 50, perforation device 30, molding device 35, etc., as well as appropriate control means (not shown).
It is configured to be synchronously controlled by and move the leaf spring materials a at a predetermined speed. According to the above configuration, the leaf spring material a is held in a predetermined shape by the holding device 50 only while it is in the transformation region from austenite to martensite and its vicinity (it is not left unattended while the conveyor 43 is moving). However, as shown in Tables 1 and 2, the amount of deformation due to quenching is substantially the same as that in conventional press quenching. In Tables 1 and 2, A is an example of the present invention, and B and C are cases of conventional press hardening and free hardening, respectively. Table 1 also shows that the leaf spring material is 20 mm thick, 90 mm wide, and 850 mm long, and the camber of the lower edge 55 of the plate body 54 is 13.5 mm.
In Table 2, the leaf spring material is 8 mm thick and wide.
60 mm, length 850 mm, and a camber of plate-shaped body 54.
In the case of 50.5 mm, the number of samples was 10 in each case. In addition, the leaf spring material a is moved in the quenching liquid 41 until it is almost completely cooled, and since the holding device 50 is not moved in or out of the quenching liquid 41, the quenching liquid 41
First, even if ordinary quenching oil is used, no oil smoke is generated, so there is no need to provide oil smoke removal means as in conventional devices. Furthermore, even when the leaf spring material is thick, the residence time in the quenching liquid 41 is long enough, so there is no need to slow down the takt time, and productivity can be improved. Moreover, since the holding device 5 is held in a predetermined shape only while in the transformation region and its vicinity,
The number of plate-shaped bodies 54, push pieces 63, etc. in 0 may be small. And the holding device 50 is made of leaf spring material a.
Since there is no need to move the hardening device along with the hardening device, the overall structure of the hardening device is simplified. In addition, the push pieces 63 disposed on the sides are swingably provided, and the plate-shaped body 54
... is provided above, the setup work is easy and the predetermined time is shortened, and even while the leaf spring material a is in the quenching tank 40, if it has passed through the holding device 50, the plate-shaped body 54... Replacement and side push piece 63
Since the position of... can be freely adjusted, it can contribute to improving the operating rate. Furthermore, since a control means for synchronously controlling each transfer device 11, 15, 42, 70 and holding device 50 is provided, the leaf spring material a can be smoothly moved at a predetermined speed, and the quenching quality can be maintained at a high level. It can be stabilized and contribute to labor saving. Moreover, by configuring as described above, the heating furnace 10, the quenching tank 40, and the tempering furnace 75 can be directly arranged, which has the effect of requiring less space. Note that the present invention is not limited to the above-described embodiment, and for example, the push piece 33 disposed on the side...
may be non-oscillating or the holding device 20
The posture of the object may be reversed upside down. In addition, various modifications and applications are possible within the scope of the gist of the present invention. As described above, the present invention includes a first transfer device that moves the leaf spring material being heated, a second transfer device that moves the heated leaf spring material to the quenching tank, and a second transfer device that moves the heated leaf spring material to the quenching tank. A third transfer device that intermittently moves the leaf spring material placed in the quenching liquid and a fourth transfer device that moves the hardened leaf spring material to the tempering furnace are continuously operated. and a holding device that holds the leaf spring material provided in the quenching tank in a predetermined shape only while at and near the transformation point from austenite to martensite and while the third transfer device stops transferring. and a control means for synchronously controlling each of the first to fourth transfer devices and the holding device. Therefore, the number of holding elements such as plate bodies and press pieces in the holding device is small, and there is no need to move them together with the leaf spring material, so the structure is simple, and a third transfer device is provided for the quenching liquid. At the same time, since the leaf spring material is held in the liquid until it is almost completely cooled, the generation of oil smoke can be minimized. Moreover, since each transfer device and holding device are controlled synchronously, it greatly contributes to improvements in productivity and quality as well as labor savings.

【table】 <

Claims (1)

[Claims] 1 A first transfer device that moves the leaf spring material being heated, a second transfer device that moves the heated leaf spring material to the quenching tank, and a second transfer device that is provided in the quenching liquid in the quenching tank. A third transfer device that intermittently moves the placed leaf spring material, and a fourth transfer device that moves the hardened leaf spring material to a tempering furnace are continuously provided, and the above-mentioned quenching a holding device provided in the tank to hold the leaf spring material in a predetermined shape while the third transfer device stops transferring; and a control means for synchronously controlling each of the first to fourth transfer devices and the holding device. A leaf spring hardening device characterized by comprising: