Rock type determination device and drilling machine

Abstract

By drilling blast holes with a crawler drill, the rock type surrounding the blast holes can be determined simultaneously. [Solution] The rock type determination device is based on determination using the differential pressure value between the actual feed pressure and the feed command pressure (differential pressure value determination). Differential pressure value determination is performed by comparing the actual feed pressure of the feed motor 11a with the feed command pressure. If the actual feed pressure of the feed motor 11a during drilling (S01:YES) is lower than the feed command pressure (SF02:YES), it is determined to be unstable rock (S03), and if it is higher (SF02:NO), it is determined to be stable rock (S04).

Description

Technical Field

[0001] The present invention relates to a rock quality determination device mounted on a drilling machine and a drilling machine.

Background Art

[0002] In a blasting method of drilling a blasting hole in a rock mass using a drilling machine, it is possible to perform the blasting work safely and efficiently by grasping the state of the rock mass. As an example of a method for grasping the rock quality, when tunneling by a drill jumbo, forward exploration is generally performed (Patent Document 1).

[0003] In tunnel excavation, after performing a boring survey from the ground surface in advance and determining the excavation route, in Patent Document 1, by using the ground classification obtained from this boring survey as reference data, it is possible to perform a more detailed forward exploration.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, unlike tunnels that need to be continuously maintained as social infrastructure, open-pit mines and quarries do not conduct boring surveys throughout the entire mining area. Therefore, it is difficult to adopt the technology of Patent Document 1 when drilling blasting holes in open-pit mines or quarries using a crawler drill. Further, Patent Document 1 is a technology for forward exploration performed under predetermined conditions prior to face excavation, and does not perform rock quality determination using the blasting holes drilled during actual work.

[0006] Furthermore, in mines and other similar environments, blasting with the appropriate explosive charge for the rock type leads to improved production efficiency and safety. In other words, it becomes easier to break the rock into the planned crushing particle size, and the amount of flying debris can also be controlled.

[0007] In view of these circumstances, the present invention aims to determine the rock type surrounding a blast hole while simultaneously drilling the blast hole with a crawler drill. [Means for solving the problem]

[0008] The first invention is a rock type determination device for determining the rock type at a location drilled by a drilling machine equipped with a rock drill and a feed mechanism for advancing the rock drill, comprising: a pressure acquisition unit for acquiring the actual feed pressure, which is the actual feed pressure supplied to the feed mechanism; a command pressure acquisition unit for acquiring the commanded feed pressure, which is the commanded value of the feed pressure; and a rock type determination unit for determining the rock type based on the values ​​acquired by the pressure acquisition unit and the values ​​acquired by the command pressure acquisition unit, wherein the rock type determination unit determines that the rock is stable if the actual feed pressure is equal to or greater than the commanded feed pressure, and determines that the rock is unstable if the actual feed pressure is less than the commanded feed pressure.

[0009] The second invention is a rock type determination device described in the first invention, further comprising a reference storage unit that sets and stores a plurality of numerical ranges for the differential pressure value, which is the difference between the actual feed pressure and the feed command pressure, and the reference storage unit stores one type of rock type classified as stable rock associated with each of the plurality of numerical ranges, and when the rock type determination unit determines that it is stable rock, it further calculates the differential pressure value and determines that it is a rock type corresponding to the numerical range in which the differential pressure value is included.

[0010] The third invention is a rock type determination device characterized in that the reference storage unit described in the second invention further stores an additional determination range in the numerical ranges between numerical ranges corresponding to rock types classified as stable rock, and the rock type determination unit determines the corresponding rock type as the determination result if the differential pressure value is included in any one of the numerical ranges corresponding to one type of rock type, and if the differential pressure value is included in the additional determination range, it further performs an additional determination, which is a rock type determination process not based on the differential pressure value, and takes the determination result of the additional determination as the final determination result.

[0011] The fourth invention is a rock type determination device characterized in that the reference storage unit described in the third invention stores at least a numerical range corresponding to hard rock, a numerical range corresponding to medium-hard rock, a numerical range corresponding to soft rock, a first additional determination range which is a numerical range between the hard rock and the medium-hard rock, and a second additional determination range which is a numerical range between the medium-hard rock and the soft rock.

[0012] The fifth invention is characterized in that the rock type determination device described in the third invention further comprises a drilling speed acquisition unit for acquiring the drilling speed and an impact pressure acquisition unit for acquiring the impact pressure of the rock drill, wherein the reference storage unit stores the relationship between the impact pressure, the actual feed pressure, and the drilling speed corresponding to the rock type classified as stable rock, and the rock type determination unit performs rock type determination as an additional determination process based on the impact pressure, drilling speed, and actual feed pressure.

[0013] The sixth invention is a drilling machine characterized by being equipped with a rock type determination device described in any of the first to fourth inventions. [Effects of the Invention]

[0014] According to the present invention, it is possible to determine the rock type surrounding a blast hole simultaneously with drilling a blast hole using a crawler drill. [Brief explanation of the drawing]

[0015] [Figure 1]It is a diagram that simplifies and shows the structure of a drilling machine according to the present invention, the blast hole, and the rock quality. [Figure 2] It is a hydraulic circuit diagram of a drilling machine according to the present invention. [Figure 3] It is a block diagram showing the configuration of a rock quality determination device according to the present invention. [Figure 4] It is a diagram showing the control flow during the drilling operation of a drilling machine according to the present invention. [Figure 5] It is a diagram showing the determination criteria stored in the reference storage unit of a drilling machine according to the present invention in a graphed manner. [Figure 6] It is a diagram showing the control flow during the drilling operation of a drilling machine according to the present invention. [Figure 7] It is the (a) rock quality map when setting a high impact pressure and (b) rock quality map when setting a low impact pressure, which are stored in the reference storage unit of a drilling machine according to the present invention.

Embodiments for Carrying Out the Invention

[0016] Embodiments of the present invention will be described with reference to the drawings as appropriate. Note that the drawings referred to are schematic. Therefore, it should be noted that the relationship between the thickness and the planar dimensions, the ratio, etc. are different from the actual ones, and there are also parts where the dimensional relationships and ratios are different between the drawings. In addition, the embodiments shown below are examples of devices and methods for embodying the technical idea of the present invention, and the technical idea of the present invention does not specify the materials, shapes, structures, arrangements, etc. of the components in the following embodiments.

[0017] As a definition of terms, in the following description, unless otherwise specified, the term "pressure" such as "feed pressure" is used as a term meaning the operating hydraulic pressure such as the operating pressure of the corresponding hydraulic equipment. Also, the terms "feed command pressure" and "actual feed pressure" used in the description are abbreviated as "command pressure" and "actual pressure" in the drawings.

[0018] <Structure of the Drilling Machine> The structure of the drilling machine will be described with reference to FIG. 1. The drilling machine 1 includes a traveling bogie 2 and a guide shell 7. The traveling bogie 2 consists of a bogie body 3, a truck frame 4, and an operator cab 5. The bogie body 3 is equipped with an engine (not shown), which is the power source of the drilling machine 1, a flushing mechanism 18, a dust collector 19, a hydraulic pump Pp (FIG. 2), various other hydraulic and pneumatic devices, and a control device 20 for controlling these hydraulic and pneumatic devices. Details of these hydraulic and pneumatic devices will be described later. At the front of the traveling bogie 2, there is a boom 6 whose rear end is supported by the traveling bogie and whose front end is connected to the guide shell 7. The boom 6 supports the guide shell 7 so that its posture can be changed within a predetermined range.

[0019] A rock drill 8 is provided on the guide shell 7 so as to be able to move forward and backward by a feed mechanism 11 that generates a propulsive force in the drilling direction. A rod 12 is attached to the rock drill 8, and a bit 13 for drilling is attached to the tip of the rod 12. The bit 13 is a component fixed to the tip of the rod 12 for crushing the rock formation and is provided only on the leading rod 12.

[0020] A rod changer 14 and a rod magazine 15 are provided on the side of the guide shell 7. A plurality of extension rods 12b without bits 13 are loaded in the rod magazine 15. When extending the extension rod 12b, the rod changer 14 takes out the extension rod 12b from the rod magazine 1 and moves it to the connection position with the rock drill 8.

[0021] The rock drill 8 includes a striking mechanism 9 for generating a striking force and a rotating mechanism 10 for generating a rotational force. Also, an openable and closable centering device 16 is provided at the tip of the guide shell 7, and a suction cap 17 is provided so as to be able to move forward and backward along the drilling direction. The impact mechanism 9 allows selection between a high impact pressure setting used during main drilling and a low impact pressure setting used during counterboring drilling. When the low impact pressure setting is selected, impact is performed at a lower impact pressure than when the high impact pressure setting is selected. In this embodiment, the high and low impact pressure settings are changed by operating an impact pressure change lever (not shown) located inside the operator cabin 5.

[0022] The centralizer 16 supports the rod 12 at the tip of the guide shell 7 and maintains a state in which the axial direction of the rod 12 is aligned with the feed direction of the rock drill 8. The suction cap 17 covers the opening of the blast hole BH during drilling operations, preventing the discharged blasting dust from scattering into the surrounding area. It is also connected to the dust collector 19 via piping. The dust collector 19 collects the dust by sucking it from the suction cap 17 via piping and discharges it from the rear of the machine.

[0023] The flushing mechanism 18 consists of a series of devices that send compressed air supplied from a compressor (not shown) to the bit 13 and inject it into the blast hole BH during drilling, generating an airflow to discharge the blasting dust to the outside of the blast hole BH.

[0024] <Configuration of the rock type determination device> The rock type determination device 50 will be described with reference to Figures 2 and 3. Note that the hydraulic circuit diagram shown in Figure 2 only illustrates the elements according to the present invention from the hydraulic pump Pp to the feed motor 11a via the feed pressure regulating valve 31 and differential pressure reducing valve 32, and elements not directly related to the present invention are omitted from the illustration.

[0025] [Hydraulic circuit configuration of a drilling machine] As shown in Figure 2, the drilling machine 1 is equipped with a feed pressure adjustment valve 31, a differential pressure reducing valve 32, and a feed forward speed adjustment valve 33 in the hydraulic circuit between the hydraulic pump Pp and the feed motor 11a. Although not shown in the diagram, a main valve, which is a control valve that distributes and supplies hydraulic fluid to each hydraulic device of the drilling machine 1, is provided between the hydraulic pump Pp and the differential pressure reducing valve 32.

[0026] The feed pressure regulating valve 31 is connected to the pilot passage (the dashed line in the figure) of the differential pressure reducing valve 32 to adjust the feed command pressure. The feed pressure regulating valve 31 may be located in the operator cabin 5 (Figure 1) and operated by the operator, or it may be controlled by the control device 20 (Figure 1).

[0027] The differential pressure reducing valve 32 is located between the main valve and the feed forward speed adjustment valve 33 and is a device that adjusts the amount of hydraulic fluid supplied to the feed motor 11a based on the feed command pressure set by the feed pressure adjustment valve 31. The feed forward speed adjustment valve 33 is located between the differential pressure reducing valve 32 and the feed motor 11a, and specifies the amount of hydraulic fluid supplied to the feed motor 11a. A tank T is provided downstream of the feed pressure regulating valve 31 and the feed motor 11a.

[0028] The differential pressure reducing valve 32 is a device that reduces the pressure from the pump (primary pressure) to a secondary pressure according to the pressure set by the feed pressure adjustment valve 31 (feed command pressure). The differential pressure reducing valve 32 includes a spring and a spool, and is structured so that the spool stops when the force generated by the secondary pressure balances the feed command pressure and the force generated by the spring. In other words, when there is a sufficient load on the feed motor 11a, the secondary pressure will be greater than the feed command pressure by the amount of the force generated by the spring.

[0029] The hydraulic circuit between the hydraulic pump Pp and the feed motor 11a is equipped with multiple sensors for acquiring numerical values ​​used for rock type identification. A feed command pressure sensor 51 is provided between the feed pressure regulating valve 31 and the differential pressure reducing valve 32 in the pilot passage of the differential pressure reducing valve 32. Furthermore, a gauge PG is connected between the feed pressure adjustment valve 31 and the differential pressure reducing valve 32 for the operator to confirm the command operating pressure. The gauge PG is located inside the operator cabin 5 shown in Figure 1. A real feed pressure sensor 52 is provided between the feed forward speed adjustment valve 33 and the feed motor 11a.

[0030] The feed command pressure sensor 51 is a command pressure acquisition unit that acquires the feed command pressure, which is the command value of the feed pressure. The actual feed pressure sensor 52 is a pressure acquisition unit that acquires the actual feed pressure, which is the actual feed pressure supplied to the rock drill 8.

[0031] Alternatively, a configuration may be provided in which a differential pressure reducing valve 32 is located downstream of the feed forward speed adjustment valve 33, and a feed motor 11a and an actual feed pressure sensor 52 are located downstream of the differential pressure reducing valve 32, that is, a configuration in which the positions of the differential pressure reducing valve 32 (including the feed pressure adjustment valve 31 and pilot passage) and the feed forward speed adjustment valve 33 are swapped in Figure 2.

[0032] [Rock quality determination device] Referring to Figure 3, the configuration of the rock type determination device 50 will be explained. The rock type determination device 50 includes, in addition to the feed command pressure sensor 51 and actual feed pressure sensor 52 described above, an impact pressure sensor 53, and further includes a drilling speed calculation unit 54, a reference storage unit 55, a rock type determination unit 56, and a rock type storage unit 57. The impact pressure sensor 53 is the impact pressure acquisition unit described in the claim, and the drilling speed calculation unit is the drilling speed acquisition unit described in the claim. Of these components, only the rock type memory unit 57 is connected to the output side of the rock type determination unit 56, while the other components are connected to the input side of the rock type determination unit 56.

[0033] The feed command pressure sensor 51 and the actual feed pressure sensor 52 are pressure sensors that acquire the feed command pressure and the actual feed pressure, respectively, as described in the hydraulic circuit configuration. The impact pressure sensor 53 is a pressure sensor provided in the hydraulic circuit of the impact mechanism 9, and acquires the impact pressure, which is the operating pressure of the impact mechanism.

[0034] The drilling speed calculation unit 54 is connected to the feed motor 11a and calculates the forward speed of the rock drill 8. The reference memory unit 55 stores information that will be referenced in the rock type determination process, which will be explained in detail later. The rock type determination unit 56 performs rock type determination processing based on the acquired and calculated information and reference values. The rock type memory unit 57 stores the determination result from the rock type determination unit, linked to the location information and drilling depth information of the blast hole BH.

[0035] <Rock type determination process> [overview] The details of the rock type determination process will be explained, mainly with reference to Figures 4 to 7. In this embodiment, the determination is based on the differential pressure value between the actual feed pressure and the feed command pressure (hereinafter referred to as "differential pressure value determination"). If the rock is determined to be stable and the differential pressure value is within a predetermined range, a determination is made using the relationship between the actual feed pressure and the drilling speed (hereinafter referred to as "additional determination").

[0036] [Distinction between stable and unstable rocks] In this invention, unstable rocks are rock types that tend to cause the operating pressure of the feed motor 11a to rise slowly, and include clay layers, fractured zones, and cavities. On the other hand, stable rocks are rock types that are stable and tend to stabilize at high operating pressures of the feed motor 11a, and include soft rocks, medium-hard rocks, and hard rocks.

[0037] In this embodiment, the distinctions between hard rock, medium-hard rock, and soft rock are relative evaluation results that can be set arbitrarily. For example, it is possible to set a rock type that is judged as hard rock at site A to be judged as soft rock at site B. Thus, in this embodiment, the criteria for rock type evaluation are set on a site-by-site basis where the drilling machine 1 is operating. Therefore, the criteria such as numerical ranges that will be illustrated and described below are merely examples.

[0038] [Differential pressure value determination] The differential pressure value is determined by comparing the actual feed pressure of the feed motor 11a with the feed command pressure. As shown in Figure 4, the rock type determination unit 56 determines the rock to be unstable (S03) if the actual feed pressure of the feed motor 11a during drilling (S01:YES) is lower than the feed command pressure (S02:YES), and determines it to be stable (S04) if it is higher (S02:NO). In other words, in the differential pressure value determination, the rock type determination unit 56 determines the rock type based on the value obtained from the pressure acquisition unit and the value obtained from the command pressure acquisition unit.

[0039] In this embodiment, a predetermined drilling depth is used as the minimum unit for determination. Specifically, while the feed motor 11a rotates by a predetermined angle, the actual feed pressure and the feed command pressure are acquired at a constant sampling interval, and the determination is made by comparing the arithmetic mean of the obtained values.

[0040] The secondary pressure from the differential pressure reducing valve 32 reaches the feed motor 11a via the hydraulic piping and the feed forward speed adjustment valve 33, but a pressure loss occurs in accordance with the flow rate during this process. Typically, when drilling stable rock, hydraulic piping and feed advance speed control valves 33 are selected to produce only minimal pressure loss, resulting in "actual feed pressure ≥ feed command pressure". On the other hand, when drilling through unstable rock, the drilling speed and feed flow rate increase, resulting in a large pressure loss where "actual feed pressure < commanded feed pressure".

[0041] After determining that the rock is stable, if further classification of the rock type is required, the feed command pressure of the feed motor 11a and the actual feed pressure are used for the determination (S05).

[0042] Figure 5 shows a graph of the information that the reference storage unit 55 refers to for "differential pressure value determination". Specifically, the reference memory unit 55 sets multiple numerical ranges for the differential pressure value, which is the difference between the actual feed pressure and the feed command pressure, and stores one type of rock classified as stable rock associated with each numerical range. Furthermore, it stores the numerical ranges between these numerical ranges corresponding to rock types classified as stable rock as additional judgment ranges.

[0043] The multiple numerical ranges, each corresponding to a single type of rock, are the numerical range corresponding to hard rock (H), the numerical range corresponding to medium-hard rock (MH), and the numerical range corresponding to soft rock (S). The diagram is drawn with the origin at the point where the differential pressure is 0 (actual feed pressure = feed command pressure), and the differential pressure increases as you move to the right (actual feed pressure > feed command pressure). Each numerical range corresponds to soft rock S, medium-hard rock MH, and hard rock H, from the lowest differential pressure side.

[0044] Furthermore, the reference memory unit 55 stores the numerical range between hard rock H and medium-hard rock MH as the first additional judgment range AJ1, and the numerical range between medium-hard rock MH and soft rock S as the second additional judgment range AJ2.

[0045] As shown in Figure 4, if the differential pressure value falls within the numerical range corresponding to any of the rock types, the rock type determination unit 56 determines the corresponding rock type as the determination result (S06-S08), and the determination result is stored in the rock type memory unit in conjunction with information on the location and drilling depth of the blast hole BH (S09).

[0046] If the differential pressure value falls within the first additional determination range AJ1 or the second additional determination range AJ2, the rock type is determined by the additional determination process (S10) described below.

[0047] [Additional judgment process] As shown in Figure 6, the additional determination process is a rock type determination method that does not use differential pressure values ​​based on impact pressure, actual feed pressure, and drilling speed, and is particularly suitable for determining stable rock. In the additional determination, first the drilling speed is calculated based on the feed rate per unit time (S11), and then, or simultaneously, the actual feed pressure is obtained (S12) and the impact pressure is obtained (S13).

[0048] The reference memory unit 55 stores a rock type map, as shown in Figure 7, in which numerical ranges corresponding to soft rock S, medium-hard rock MH, and hard rock H are set according to the drilling speed relative to the actual feed pressure. The rock type map summarizes information on drilling speed in relation to feed pressure and rock hardness.

[0049] The diagram shows that the drilling speed increases as you move to the right, with the lower left as the origin, and the actual feed pressure increases as you move upwards. In other words, it has been visualized that the slower the drilling speed when operated at a certain feed pressure, the harder the rock, and the higher the actual feed pressure required to achieve a certain drilling speed, the harder the rock.

[0050] Since the level of impact pressure corresponds to the level of energy input during drilling, the position at which hard rock H is identified differs between the graph in Figure (a), which shows high impact pressure, and the graph in Figure (b), which shows limited impact pressure. Specifically, in the graph in Figure (b), which shows low impact pressure settings, the numerical ranges indicating each rock type are shifted to the right compared to Figure (a). In other words, it shows the criteria for judgment when the drilling speed is slower than the amount of feed pressure applied.

[0051] The rock type map referenced during rock type determination based on additional determination needs to change depending on the impact pressure during drilling. Therefore, before the rock type determination process, the rock type map is switched based on the acquired impact pressure (S14). In this embodiment, the rock type map for high impact pressure settings shown in Figure (a) and the rock type map for low impact pressure settings shown in Figure (b) are switched. This is a method for correcting the rock type map assuming a drilling machine 1 configured so that the operator does not set the impact pressure in detail, but only switches between pre-defined impact modes. For this reason, it is also possible to store a calculation formula for correction in the reference storage unit 55 and perform the rock type map correction each time. As shown in Figure 6, after switching the rock type map, the rock type determination unit 56 uses the drilling speed and actual feed pressure to determine the rock type by referring to the rock type map (S15-S18).

[0052] Then, the judgment result from the additional judgment process is stored in the rock type memory unit 57 as the final judgment result, linked to the information on the drilling depth (Figure 4: S09). By repeating the above determination process, rock type information for the entire area within the blast hole (BH) is recorded.

[0053] <Effects> This invention makes it possible to determine the rock type surrounding a blast hole while drilling it with a crawler drill. Therefore, there is no need for test drilling or post-drilling investigations, and it is possible to record information related to the rock type while drilling the blast hole.

[0054] Furthermore, this invention distinguishes between stable rock and unstable rock as the largest classification units. In particular, unstable rock can cause problems during the charging process and is also prone to causing overcharging. Therefore, by identifying the location of unstable rock in advance, it becomes easier to create an appropriate charging plan and allows for prior consideration of how to proceed with the charging process, thus providing beneficial effects in the charging process. Furthermore, classifying stable rocks in detail based on their hardness makes it easier to create an appropriate explosive charge plan.

[0055] While it is possible to distinguish between unstable and stable rock based solely on drilling speed, the accuracy of the determination will decrease. This is because, in actual drilling operations, the operator of drilling machine 1 may intentionally reduce the feed rate, feed pressure, and impact pressure to decrease the drilling speed in order to avoid jamming, hole curvature, etc. In other words, if one constantly attempts to determine the rock type based solely on drilling speed, the drilling parameters will fluctuate regardless of the rock type, thus reducing the accuracy of the determination. This invention uses the differential pressure between the actual feed pressure, which is less affected by operator actions, and the feed command pressure to make the determination, thus enabling a more accurate determination than methods that determine rock type based solely on drilling speed.

[0056] As shown in the embodiment, it is possible to improve the accuracy of the judgment by setting an additional judgment range between each numerical range and performing additional judgment processing. In other words, in sites where differential pressure values ​​often oscillate across thresholds determined to be adjacent rock types, it is possible to prevent the judgment result from changing in a short period of time.

[0057] <Variation> The above embodiment describes a rock type determination device that uses differential pressure value determination and additional determination in combination. However, the essence of the present invention lies in determining stable and unstable rock by comparing the differential pressure between the actual feed pressure for driving the feed motor 11a and the feed command pressure. Therefore, setting the additional determination range and adopting the additional determination are optional. Alternatively, the device may be configured to only distinguish between stable and unstable rock. [Explanation of symbols]

[0058] 1...Drilling machine, 8...Rock drilling machine, 9...Impact mechanism, 10...Rotation mechanism, 11...Feed mechanism, 11a...Feed motor, 20...Control device, 31...Feed pressure adjustment valve, 32...Differential pressure reducing valve, 33...Feed forward speed adjustment valve, 50...Rock type determination device, 51...Feed command pressure sensor, 52...Actual feed pressure sensor, 53...Impact pressure sensor, 54...Drilling speed calculation unit, 55...Reference memory unit, 56...Rock type determination unit, 57...Rock type memory unit, H...Hard rock, MH...Medium-hard rock, S...Soft rock, AJ1...First additional determination range, AJ2...Second additional determination range

Claims

1. A rock type determination device for determining the rock type at the location where a drilling machine is drilling, the device comprising a rock drill and a feed mechanism for advancing the rock drill, A pressure acquisition unit that acquires the actual feed pressure, which is the actual feed pressure supplied to the feed mechanism, A command pressure acquisition unit acquires the feed command pressure, which is the command value of the feed pressure, The system includes a rock type determination unit that determines the rock type based on the acquired value from the pressure acquisition unit and the acquired value from the command pressure acquisition unit. The rock type determination device is characterized in that the rock type determination unit determines that the rock is stable if the actual feed pressure is equal to or greater than the feed command pressure, and determines that the rock is unstable if the actual feed pressure is less than the feed command pressure.

2. Furthermore, it includes a reference storage unit that stores multiple numerical ranges for the differential pressure value, which is the difference between the actual feed pressure and the feed command pressure, that can take place. The reference storage unit stores one type of rock classified as stable rock for each of the multiple numerical ranges. The rock type determination device according to claim 1, characterized in that when the rock type determination unit determines that the rock is stable, it further calculates the differential pressure value and determines that the rock type corresponds to the numerical range in which the differential pressure value is included.

3. The aforementioned reference storage unit further stores additional determination ranges in the numerical ranges between numerical ranges corresponding to rock types classified as stable rock. The rock type determination unit is, If the differential pressure value falls within any one of the numerical ranges corresponding to one of the rock types, the corresponding rock type is determined as the result. The rock type determination device according to claim 2, characterized in that if the differential pressure value falls within the additional determination range, an additional determination is performed, which is a rock type determination process not based on the differential pressure value, and the determination result of the additional determination is taken as the final determination result.

4. The rock type determination device according to claim 3, characterized in that the reference storage unit stores at least a numerical range corresponding to hard rock, a numerical range corresponding to medium-hard rock, a numerical range corresponding to soft rock, a first additional determination range which is a numerical range between the hard rock and the medium-hard rock, and a second additional determination range which is a numerical range between the medium-hard rock and the soft rock.

5. Furthermore, a drilling speed acquisition unit acquires the drilling speed, The system includes an impact pressure acquisition unit that acquires the impact pressure of the rock drill, The aforementioned reference memory unit stores the relationship between the impact pressure, the actual feed pressure, and the drilling speed, corresponding to the rock type classified as stable rock. The rock type determination device according to claim 3, characterized in that the rock type determination unit performs rock type determination based on the impact pressure, drilling speed, and actual feed pressure as the additional determination.

6. A drilling machine characterized by comprising a rock type determination device according to any one of claims 1 to 5.

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