JP2681926B2 - Honing machine - Google Patents

Description

TECHNICAL FIELD The present invention relates to a honing device that performs honing processing more quickly and more accurately. [Prior Art] FIG. 4 is an explanatory diagram for explaining a situation in which the diameter of the hole of the product gradually increases when honing is performed by the conventional method. In Fig. 4, 1 indicates the product to be honed, and indicates the target size to be obtained by honing. Further, 3 represents the edge of the hole 4 before the honing process. The hole 4 before honing is usually finished by boring. Conventionally, the honing process for the holes 4 of the article 1 has been performed as follows. That is, in the initial stage of processing from the diameter marked with 3 to the diameter marked with, honing is performed at a relatively fast speed until the diameter marked with changes to the diameter marked with. In the middle stage of machining, machining was performed at a medium speed, and at the final stage of machining from the diameter marked with to the target dimension marked with, honing was performed at a slow speed. The speed of honing is proportional to the pressing force (hereinafter referred to as expansion pressure) that presses the grindstone (not shown) against the wall surface of the hole 4, so from the diameter marked with 3 to the diameter marked with As shown in Fig. 5, increase the expansion pressure of the grindstone to P1 and increase the expansion pressure from P2 to the diameter of The expansion pressure was lowered to P3 until the target diameter indicated by was reached. Here, FIG. 5 is a graph showing the relationship between the diameter of the hole and the expansion pressure when honing is performed by the conventional method. Fifth
In the figure, and on the horizontal axis respectively indicate the position of the diameter of the hole 4. Is the target size. The positions of the diameters of the holes 4 correspond to the positions marked with respectively in FIG. The horizontal axes P1, P2, and P3 respectively represent the hydraulic pressures in the hydraulic chambers of the hydraulic cylinder (not shown) corresponding to the expansion pressure of the grindstone. Each size is P1>P2>
It is said to be P3. P1 is about 15 Kg / cm ² approximately, P2 is approximately 4 Kg / cm ² approximately, P3 is about 3 Kg / cm ² approximately. The expansion pressure was divided into multiple stages. If a high expansion pressure is applied to the grindstone from the beginning, the honing speed is high and the productivity is high, but there is a possibility that the product may be rejected if it exceeds the target size. If a low expansion pressure is applied to the grindstone from the beginning, it will surely finish according to the target size, but instead, the honing speed will be slow and productivity will be low. Therefore, in order to achieve both productivity and accuracy, the expansion pressure is divided into multiple stages. [Problems to be Solved by the Invention] However, the conventional device described with reference to FIG. 4 or 5 also has the following problem. That is, the first expansion pressure P1 may be relatively high, but if the second expansion pressure P2 is increased, the initial boring process also has variations, and depending on the product, it is over-cut and the hole 4 The diameter may be larger than the target size, so I had to set P2 to a small value. Therefore, the processing time to reach the target dimension will be longer. This is a problem of the conventional technique. The present invention is to solve the above-mentioned problems of the prior art. The technical problem of the present invention is to reduce the machining time in the middle stage of machining which has a large amount of machining and may affect the target diameter of the hole when honing the hole of the product,
Another object of the present invention is to provide a honing device capable of maintaining the honing accuracy of the hole of the product. [Means for Solving Problems] In order to solve this technical problem, the following means are taken in the present invention. That is, the honing machine according to the present invention is
A honing machine for honing a hole in an item, the grindstone abutting the hole of the item and rotating and sliding to perform honing, a pressure means for applying an expanding pressure to the whetstone, and a diameter of the hole in the item are measured. In a honing machine equipped with a size sensor and a control means for receiving a signal from the size sensor and determining the expansion pressure of the grindstone, the control means corresponds to the expansion pressure during the honing process at the initial stage of processing. A first means that can be controlled in three stages of high pressure, medium pressure corresponding to the middle stage of machining, and low pressure corresponding to the last stage of machining, and maintaining or increasing or decreasing the expansion pressure in the medium pressure region of the middle stage of machining. And a second control means for making a determination based on the diameter of the hole and a processing time and determining the expansion pressure in the middle of the processing based on the result of the determination. To. [Effect] According to the present invention, of the three stages of the initial stage, the middle stage, and the final stage of machining, the expansion pressure in the middle stage of machining which has a large amount of machining of the product and may affect the target size of the hole. Whether to maintain or raise or lower is determined based on the diameter of the hole and the processing time, and based on the result of the determination. Therefore, it is possible to increase the expansion pressure within a range where the product is not excessively cut, the cutting efficiency of the grindstone is improved as much as possible, and the honing time can be shortened. In addition, the expansion pressure of the grindstone is controlled in the middle stage of processing based on the diameter of the hole of the item and the processing time, and the expansion pressure is controlled in the medium pressure range and set in the high pressure range. Therefore, even if there are variations in the hole diameter of the product before honing, over-shaving of the product hole is suppressed and the honing accuracy can be maintained. Thus, according to the present invention, the honing processing time can be shortened as compared with the conventional one. Further, according to the present invention, when the expanding pressure of the grindstone changes on the way, unnecessary abrasive grains fall off from the grindstone each time. Therefore, there is also an advantage that the self-reaction of the grindstone is accelerated. [Embodiment] FIG. 1 is an overall configuration diagram of a honing apparatus according to an embodiment of the present invention. In FIG. 1, 1 is an item to be honed, and the figure is a diagram in which the hole 4 of the item 1 is honed. Item 1 is specifically the large end of the connecting rod. Reference numeral 11 is a diamond grindstone for honing. Honing is performed by pressing the grindstone 11 against the inner wall surface of the hole 4 and rotating and sliding it. The grindstone 11 is attached to a grindstone holding member 12 made of resin. The grindstone holding member 12 is attached to the horn head 13 so as to be slidable in the radial direction. The horn head 13 is fixed to a hydraulic cylinder 14 by bolts (not shown), and the hydraulic cylinder 14 is driven by a driving device 15
Is designed to rotate in the direction of arrow A. The hydraulic cylinder 14 is made to slide in the direction of arrows BC by the drive device 15. By this rotation and sliding, the grindstone 11 evenly horns the holes 4. The expansion pressure that pushes the grindstone 11 against the inner wall surface of the hole 4, that is, the expansion pressure is given by the conical taper cone 21. That is,
A piston 19 is slidably accommodated in the hydraulic cylinder 14, and the rod 16 is connected to the piston 16 from the piston 19.
The taper cone 21 mentioned above is attached to the tip of the rod 16. When the piston 19 is moved in the direction of arrow B, the taper cone
Since 21 is a taper surface and pushes the grindstone holding member 12, the expansion pressure of the grindstone 11 increases. Conversely, when the piston 19 is moved in the direction of arrow C, the expansion pressure of the grindstone 11 decreases. What moves the piston 19 in the direction of arrow B or arrow C is the hydraulic pressure supplied to the hydraulic chambers 22 and 23. Reference numerals 24 and 25 denote a first hydraulic pipe and a second hydraulic pipe for supplying hydraulic pressure to the hydraulic chambers 22 and 23, respectively. The hydraulic cylinder 14, the piston 19, the taper cone 21 and the like correspond to the pressure means in the present invention. The first hydraulic pipe 24 and the second hydraulic pipe 25 are not directly connected to the hydraulic cylinder 14 because the hydraulic cylinder 14 rotates. The hydraulic cylinder 14 is arranged in a case (not shown), and an annular hydraulic groove (not shown) is provided around the hydraulic cylinder 14. The hydraulic pressure is supplied from the first hydraulic pipe 24 and the second hydraulic pipe 25 to the annular hydraulic groove. Of course, the hydraulic groove is not shown O
The oil pressure does not leak because it is sealed by the ring. In FIG. 1, reference numeral 26 is an oil tank, and the oil in the oil tank 26 is pumped up by an oil pump 31. During the honing process, the oil pumped by the oil pump 31 as indicated by the arrow D is always the third hydraulic pipe.
Flowing from 34 through the switching valve 33 to the first hydraulic pipe 24, it is supplied to the hydraulic chamber 22 as indicated by arrow D. The switching valve 33 is the third valve when the honing process is completed.
The hydraulic pipe 34 is connected to the second hydraulic pipe 25, and the first hydraulic pipe 24 is connected to the fourth hydraulic pipe 35. As a result, the oil in the hydraulic chamber 22 becomes the first hydraulic pipe.
It is returned to the oil tank 26 through 24 and the fourth hydraulic pipe 35. The honing machine shown in FIG.
And converter 42, sizing device 43, amplifier 44 and hydraulic relief valve 45
Are provided. These control the amount of honing processing. As can be seen from the figure, the air nozzle 41 has a horn head 13
The air nozzle 41 is adapted to inject air through a route (not shown). The diameter of the hole 4 is measured by the pressure of the jetted air. The signal is sent to the converter 42 via the air hose 39, converted into a voltage signal by the converter 42, and sent to the sizing device 43. The air nozzle 41 corresponds to the dimension sensor referred to in the present invention. Since the horn head 13 rotates in the air hose 39,
It is not directly connected to the horn head 13. The first hydraulic pipe 24 and the second hydraulic pipe 25 described above are connected in the same manner. The sizing device 43 converts the voltage generated by the converter 42 into the size of the inner diameter of the hole 4. In addition, the sizing device 43 stores a target dimension, and several sizes between the target dimension and the inner diameter at the beginning of processing in order, six dimensions in total.
When the diameter of the hole 4 gradually becomes those dimensions as it is processed, it has a function of changing the expansion pressure of the grindstone 11, in other words, the pressure of the hydraulic chamber 22 of the hydraulic cylinder 14. Since this is a feature of this embodiment, this point will be described in detail. FIG. 2 is an explanatory diagram for explaining the function of the sizing device. In Fig. 2, the abscissa ,,,, are the items 1 stored in the sizing device (43 in Fig. 1).
The position of the diameter of the hole 4 is shown. Is the target size. The positions of the diameters of these holes 4 are respectively marked in FIG. FIG. 3 is an explanatory view for explaining how the diameter of the hole of the product gradually increases when honing is performed. In FIG. 3, 3 is the edge of the hole 4 at the beginning of honing, which is the target dimension. The state before honing processing corresponds to the initial processing,
Items from to to correspond to the middle stage of machining, and items to to correspond to the final stage of machining. Returning to FIG. 2, the vertical axes P1, P2, P3, P4, P5, P6, and P7 are hydraulic chambers corresponding to the expansion pressure of the grindstone 11 (2 in FIG. 1).
2) Indicates the hydraulic pressure. Each size is P1>P4> P
5>P6>P7>P2> P3, where P1 corresponds to the high pressure of the present invention, P2, P4, P5, P6 and P7 correspond to the medium pressure, and P3 corresponds to the low pressure. P1 is about 15Kg / cm ² about, P2 is about 4Kg / cm ² about, P3 is about 3
It is about Kg / cm ² . As can be seen from FIG. 2, the pressure in the hydraulic chamber 22 starts at P1 when the first machining is started. Honing is very fast because P1 has a very high hydraulic pressure. Next, when the diameter of the hole 4 becomes, the sizing device 43 gives a signal to that effect. At the same time, the sizing device 43 drops the hydraulic pressure to P2 and holds it in that state for the time of T1. Of course, during this time, the honing process proceeds as it is, but the sizing device 43 raises the hydraulic pressure to P4 if the next sizing dimension is not reached even after the time T1 has elapsed. Then hold at that value for t ₁ . This hydraulic pressure P4 is not as high as P1, but it is the highest value after P1, so honing proceeds relatively quickly. Next, even if the time of t ₁ elapses, the sizing device 43 drops the hydraulic pressure to P 2 if the next sizing dimension is not reached. Then, the honing process is continued. When the next diameter is reached, the sizing device 43 gives a signal to that effect. The sizing device 43 holds the hydraulic pressure at P2 and holds it for the time of T2. During this time, honing continues, but T2
If the next fixed dimension is not reached even after the lapse of time, the sizing apparatus 43 raises the hydraulic pressure to P5. Then, hold that value for the time t ₂ . This hydraulic pressure P5 is not as high as P4, but it is a high value for P4, so honing proceeds relatively quickly. Then, when the diameter of the hole 4 approaches, the hydraulic pressure is returned to P2,
If the diameter of the hole 4 does not reach the maximum even after a lapse of time T3 from when the diameter of the hole 4 becomes, increase the hydraulic pressure to P6.
Hold for time t ₃ . Further, when the diameter of the hole 4 is approached, the hydraulic pressure is returned to P2.
If the diameter of hole 4 does not reach the maximum even after T4 has elapsed, adjust the hydraulic pressure to P7.
It is raised to and holds the hydraulic P7 by the time t _4. In this way, when the diameter of the hole 4 approaches, the hydraulic pressure is returned to P2, and when the diameter of the hole 4 becomes, the hydraulic pressure is set to a value P3 that is one time lower until the target dimension from, and honing is performed at a very slow speed. Advance processing. In addition, at the stage of shifting from to,
If the hydraulic pressure drops to P2 and the processing proceeds until the next fixed dimension is reached before the time T1 elapses, the sizing device 43 keeps the hydraulic pressure as it is and stops at that value until the time T2 elapses. In this way, the oil pressure may not be increased from P2 in some cases. The same applies to t ₁ . The same applies to the other stages of transitioning to. As can be seen from the above description, the sizing device 43 controls the entire honing device shown in FIG. The control signal as described above is amplified by the amplifier 44 of FIG. 1 and transmitted to the hydraulic pressure relief valve 45. It is the hydraulic relief valve 45 that actually controls the hydraulic pressure in the hydraulic chamber 22 as described above. That is, the relief valve 45 relieves the hydraulic pressure supplied from the oil pump 31 so that the hydraulic pressure in the hydraulic chamber 22 becomes the above value. The operation of the present embodiment will be described. As described above, in the conventional case, if the second expansion pressure P2 in FIG. 5 is increased, the diameter of the hole 4 may become too large than the target value because of excessive cutting, so
As you can see from the figure, I had to set a small value for P2. Therefore, the processing time to reach the target size was long. On the other hand, in the present embodiment, as can be seen from the explanation of FIG. 2, the region where the medium pressure is maintained is divided into several parts, and the expansion pressure is locally increased as much as possible in each part. ing. In other words, whether to increase the expansion pressure in the medium pressure region or hold it as it is is finely determined based on the diameter of the hole 4 and the processing time, and based on the result of the determination, the expansion pressure is maintained in the medium pressure region. Rising / returning is decided, and the expansion pressure once set in the medium pressure region is not maintained until the end, but the expansion pressure is made as high as possible. Therefore, it is possible to increase the expansion pressure within the range where the product is not cut too much.
The cutting efficiency of the grindstone 11 is improved as much as possible, and the honing time can be shortened. Further, the expansion pressure of the grindstone 11 is controlled based on the diameter of the hole 4 of the article 1 and the processing time, and the expansion pressure is controlled at the intermediate pressures P2, P4, P.
Since it is performed in the area of 5, P6, P7 and is not set in the area of high pressure P1, even if the diameter of the hole 4 of the product 1 before honing processing varies, the hole 4 of the product 1 is scraped. Excess is suppressed and honing accuracy can be maintained. Thus, according to this embodiment, the processing time of honing can be shortened as compared with the conventional one. Incidentally, conventionally, it took about 30 seconds to process the hole 4 at the large end of the connecting rod, but according to the present embodiment, the honing process is completed in about 10 seconds without variation. As can be seen from the above description, the control device according to the present invention corresponds to the sizing device 43 in this embodiment. As can be seen from Fig. 1, the sizing device 43 has a high expansion pressure P1 and a medium expansion pressure P2, P4, P5, P6, P7 for the expansion pressure during honing.
And the first means 51 that can change the pressure to low pressure P3, and any of the hydraulic pressures P4, P5, P6, and P7 that are higher than the hydraulic pressure P2 based on the diameter of the hole 4 of the product 1 and the honing processing time. The second means 52 is provided to determine whether the honing process is continued with the hydraulic pressure P2, and to determine the expansion pressure in the intermediate pressure region based on the determination result. According to the present embodiment, the expanding pressure of the grindstone 11 changes in several steps on the way, so that the unnecessary abrasive grains fall off from the grindstone 11 each time. Therefore, there is an advantage that the self-generated action of the grindstone 11 is promoted and the clogging of the grindstone 11 is eliminated. The specific embodiment of the present invention has been described above, but the present invention is not limited to this embodiment, and various embodiments are included within the scope of the claims. [Effects of the Invention] According to the present invention, of the three stages of the initial stage of machining, the middle stage of machining, and the final stage of machining, the amount of machining of the product is large and the expansion in the middle stage of machining which may affect the target size of the hole Whether the pressure is maintained or increased or decreased is determined based on the diameter of the hole and the processing time, and based on the result of the determination. Therefore, it is possible to increase the expansion pressure within a range in which the product is not excessively cut, the cutting efficiency of the grindstone is improved as much as possible, and the honing time can be shortened. In addition, the expansion pressure of the grindstone is controlled in the middle stage of processing based on the diameter of the hole of the item and the processing time, and the expansion pressure is controlled in the medium pressure range and set in the high pressure range. Therefore, even if there are variations in the hole diameter of the product before honing, over-shaving of the product hole is suppressed and the honing accuracy can be maintained. Therefore, according to the present invention, it becomes possible to significantly reduce the processing time of honing processing as compared with the conventional one.
This has the effect. Further, according to the present invention, when the expanding pressure of the grindstone changes on the way, unnecessary abrasive grains fall off from the grindstone each time. Therefore, the self-generated action of the grindstone is promoted, and the clogging of the grindstone is also eliminated.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an overall configuration diagram of a honing device according to an embodiment of the present invention, FIG. 2 is an explanatory diagram for explaining the function of a sizing device, and FIG. , Fig. 4 is an explanatory view for explaining how the hole diameter of the product gradually increases when honing, and Fig. 4 explains how the hole diameter of the product gradually increases when honing by the conventional method. And FIG. 5 are graphs showing the relationship between the hole diameter and the expansion pressure when honing is performed by the conventional method. 1 …… Item 4 …… Hole 11 …… Whetstone 14,19,21 …… (Pressure means) 14 …… Hydraulic cylinder 19 …… Piston 21 …… Taper cone 41 …… Air nozzle (Dimension sensor) 43 …… Sizing device (Control means) 51 ... First means 52 ... Second means

Claims (1)

(57) [Claims] A honing machine for honing a hole in an item, the grindstone abutting the hole of the item and rotating and sliding to perform honing, a pressure means for applying an expanding pressure to the whetstone, and a diameter of the hole in the item are measured. In a honing machine comprising a size sensor and a control means for receiving a signal from the size sensor and determining the expansion pressure of the grindstone, the control means corresponds to the expansion pressure during the honing process in the initial stage of processing. First means capable of controlling in three stages of high pressure, medium pressure corresponding to the middle stage of machining, and low pressure corresponding to the last stage of machining, and maintaining or raising or lowering the expansion pressure in the medium pressure region of the middle stage of machining. , A second control means for making a determination based on the diameter of the hole and the processing time and for determining the expansion pressure in the middle stage of the processing based on the result of the determination. Honing device to.