Bridge type conveyance vehicle and method for calculating the rotation amount of a winding drum in a bridge type conveyance vehicle

Abstract

The present application relates to a bridge conveyor and a method for calculating the rotation amount of a winding drum in the bridge conveyor, and enables a lifting platform to be reliably lifted to a desired height position even in the case where there are individual differences in the bridge conveyor. A bridge conveyor (1) is provided with a lifting platform (7) that moves a load, a winding drum (61) that overlaps and winds a tape (B) mounted to the lifting platform, and a controller (8) that controls the lifting amount of the lifting platform by controlling the rotation amount of the winding drum. The controller (8) performs: a first process of calculating an individual value (L0) of the full length of the tape, an individual value (D) of the diameter of the winding drum, and an individual value (t) of the thickness of the tape as individual values of the bridge conveyor; and a second process of calculating the rotation amount of the winding drum with respect to the lifting amount of the lifting platform based on the individual value (L0) of the full length of the tape, the individual value (D) of the diameter of the winding drum, and the individual value (t) of the thickness of the tape calculated in the first process.

Description

Technical Field

[0001] This invention relates to a bridge-type conveyor and a method for calculating the rotation amount of the winding roller in the bridge-type conveyor. Background Technology

[0002] A bridge-type conveyor is known, which includes a lifting platform for transferring items, a take-up drum for overlapping and winding a lifting member installed on the lifting platform, and a controller for controlling the lifting amount of the lifting platform by controlling the rotation amount of the take-up drum (for example, see Patent Document 1).

[0003] Patent Document 1: Japanese Patent Application Publication No. 2019-43720

[0004] In the aforementioned technique, the thickness of the inherent lifting components of the bridge conveyor is determined, and this determined thickness is used to determine the rotation amount of the winding drum relative to the lifting amount of the lifting platform. Therefore, when the lifting platform is raised to the desired height (transfer height), the effects caused by individual variations in the thickness of the lifting components can be suppressed. However, even in this case, it cannot be said that individual variations of the bridge conveyor have been fully considered; the lifting platform may actually deviate from the desired height after raising, and there is still room for improvement. Summary of the Invention

[0005] Therefore, the purpose of this invention is to provide a bridge conveyor and a method for calculating the rotation of the winding roller in the bridge conveyor, so that even if there are individual differences in the bridge conveyor, the lifting platform can be reliably raised and lowered to the desired height position.

[0006] The bridge conveyor of the present invention includes a lifting platform for transferring items, a take-up drum for overlapping and winding a lifting member mounted on the lifting platform, and a controller for controlling the lifting amount of the lifting platform by controlling the rotation amount of the take-up drum. In this bridge conveyor, the controller performs: a first process, calculating an individual value of the total length of the lifting member, an individual value of the diameter of the take-up drum, and an individual value of the thickness of the lifting member as individual values ​​of the bridge conveyor; and a second process, calculating the rotation amount of the take-up drum relative to the lifting amount of the lifting platform based on the individual values ​​of the total length of the lifting member, the individual value of the diameter of the take-up drum, and the individual value of the thickness of the lifting member calculated in the first process.

[0007] In this bridge-type conveyor, the individual values ​​of the total length of the lifting component, the diameter of the winding drum, and the thickness of the lifting component are calculated. Based on these individual values, the rotation amount of the winding drum relative to the lifting amount of the lifting platform is calculated. Therefore, the rotation amount of the winding drum relative to the lifting amount of the lifting platform can be determined by fully taking into account the individual differences of the bridge-type conveyor. Consequently, even when there are individual differences in the bridge-type conveyor, the lifting platform can be reliably raised and lowered to the desired height.

[0008] In the bridge-type conveyor of the present invention, in the first process, the lifting amount of the lifting platform is approximated by a square function of the rotation amount of the winding drum, thereby calculating the individual values ​​of the total length of the lifting member, the diameter of the winding drum, and the thickness of the lifting member. This square function includes, as coefficients, the individual values ​​of the total length of the lifting member, the diameter of the winding drum, and the thickness of the lifting member. Through intensive research, the inventors have discovered that the lifting amount of the lifting platform can be approximated by a square function of the rotation amount of the winding drum, which includes, as coefficients, the individual values ​​of the total length of the lifting member, the diameter of the winding drum, and the thickness of the lifting member. Therefore, by using this approximation, these individual values ​​can be calculated simply and accurately.

[0009] In the bridge-type conveyor of the present invention, in the first process, based on a data set containing two or more sampled data, the individual values ​​of the total length of the lifting member, the individual value of the diameter of the winding drum, and the individual value of the thickness of the lifting member are calculated. This sampled data consists of the lifting amount of the lifting platform and the rotation amount of the winding drum during that lifting amount. In this case, the individual values ​​of the total length of the lifting member, the individual value of the diameter of the winding drum, and the individual value of the thickness of the lifting member can be easily and accurately determined using the data set.

[0010] In the bridge-type conveyor of the present invention, in the first process, the individual values ​​of the total length of the lifting member, the individual value of the diameter of the winding drum, and the individual value of the thickness of the lifting member are calculated based on the following formulas (1) to (6). As a result, the individual values ​​of the total length of the lifting member, the individual value of the diameter of the winding drum, and the individual value of the thickness of the lifting member can be obtained more simply and accurately.

[0011]

Formula 1

[0012] L = An 2 +Bn+C…(1)

[0013] -πt=A…(2)

[0014] π(D+2tn0)=B…(3)

[0015] L0-πn0(D+tn0)=C=0…(4)

[0016]

[0017]

[0018] Where, L: lifting amount of the lifting platform, n: rotation amount of the winding drum, t: individual value of the thickness of the lifting element, D: individual value of the diameter of the winding drum, L0: individual value of the total length of the lifting element, n0: rotation amount of the winding drum when the lifting platform is at the origin position, N: number of samples (an integer greater than 2), n i L represents the rotation amount of the take-up roller in the i-th sample. i : The lifting amount of the lifting platform in the i-th sample.

[0019] In the bridge-type conveyor of the present invention, the controller may perform: a first data acquisition process, in which, with the lifting platform at its origin, a distance detected by a sensor is acquired as a first distance, the sensor detecting the distance between a first measuring component held on the lifting platform and a second measuring component disposed directly below the first measuring component; a second data acquisition process, in which, with the lifting platform raised or lowered by a set amount, a distance detected by the sensor is acquired as a second distance, and the value obtained by subtracting the first distance from the second distance and the rotation amount of the winding roller at the set amount of raising or lowering are acquired as the amount of raising or lowering of the lifting platform and the rotation amount of the winding roller in the sampled data; and a third data acquisition process, in which the set amount of raising or lowering is changed and the second data acquisition process is repeatedly executed. Thus, at least two sampled data points can be automatically acquired.

[0020] The bridge-type transport vehicle of the present invention may also be equipped with an input unit capable of inputting a set lifting amount in each of the multiple second data acquisition processes. In this case, each set lifting amount can be appropriately input via the input unit.

[0021] In the bridge-type conveyor of the present invention, in the second process, the rotation amount of the take-up roller relative to the lifting amount of the lifting platform is calculated based on the following formula (7). Thus, the rotation amount of the take-up roller relative to the lifting amount of the lifting platform can be calculated simply and accurately.

[0022]

Formula 2

[0023] L=L0-π(D(n0-n)+t(n0-n) 2 )…(7)

[0024] Where L: the lifting amount of the lifting platform, n: the rotation amount of the winding drum, t: the individual value of the thickness of the lifting component, D: the individual value of the diameter of the winding drum, L0: the individual value of the total length of the lifting component, and n0: the rotation amount of the winding drum when the lifting platform is at the origin position.

[0025] The present invention discloses a method for calculating the rotation amount of a winding drum in a bridge-type conveyor. The bridge-type conveyor includes a lifting platform for transferring items, a winding drum that overlaps and winds a lifting member mounted on the lifting platform, and a controller that controls the lifting amount of the lifting platform by controlling the rotation amount of the winding drum. The method includes: a first step of calculating, as individual values ​​of the bridge-type conveyor, the individual value of the total length of the lifting member, the individual value of the diameter of the winding drum, and the individual value of the thickness of the lifting member; and a second step of calculating, based on the individual values ​​of the total length of the lifting member, the individual value of the diameter of the winding drum, and the individual value of the thickness of the lifting member calculated in the first step, the rotation amount of the winding drum relative to the lifting amount of the lifting platform.

[0026] In the method for calculating the rotation amount of the winding drum in this bridge conveyor, individual values ​​of the total length of the lifting component, the diameter of the winding drum, and the thickness of the lifting component are calculated. Based on these individual values, the rotation amount of the winding drum relative to the lifting amount of the lifting platform is calculated. Therefore, the rotation amount of the winding drum relative to the lifting amount of the lifting platform can be determined by fully taking into account the individual differences of the bridge conveyor. Consequently, even when there are individual differences in the bridge conveyor, the lifting platform can be reliably raised and lowered to the desired height.

[0027] The effects of the invention

[0028] According to the present invention, even in the case of individual differences in the bridge-type conveyor vehicles, the lifting platform can be reliably raised and lowered to the desired height position. Attached Figure Description

[0029] Figure 1 This is a side view of a bridge-type transport vehicle according to one embodiment.

[0030] Figure 2 It means Figure 1 A schematic diagram of the lifting drive unit.

[0031] Figure 3 (a) is an explanation of... Figure 1 A side view of the winding drum rotation when the lifting platform is at the origin position in a bridge-type conveyor. Figure 3 (b) means Figure 3 The subsequent side view of (a).

[0032] Figure 4 (a) is used to explain Figure 1 The first to third data in the bridge-type conveyor are obtained using the processed side view. Figure 4 (b) means Figure 4 The subsequent side view of (a).

[0033] Figure 5 It is a graph representing the error between the rotation amount of the take-up drum and the lifting amount of the lifting platform.

[0034] Figure 6 (a) is used to explain Figure 1 The first to third data in the bridge-type conveyor are obtained using other side views processed. Figure 6 (b) means Figure 6 The subsequent side view of (a).

[0035] Explanation of symbols

[0036] 1: Bridge conveyor; 61: Winding roller; 7: Lifting platform; 8: Controller; 9: Input unit; 11, 91: First measuring component; 12, 92: Second measuring component; 81, 82: Sensor; 200: FOUP (item); B: Belt (lifting component). Detailed Implementation

[0037] Hereinafter, one embodiment will be described with reference to the accompanying drawings. In the description of the drawings, the same elements are labeled with the same symbols and repeated descriptions are omitted. The dimensions of the drawings are not necessarily consistent with the objects being described.

[0038] like Figure 1 As shown, in one embodiment, a bridge-type transport vehicle 1 travels along a track 100 laid near the ceiling of a cleanroom for manufacturing semiconductor equipment. In one embodiment, the bridge-type transport vehicle 1 transports a FOUP (Front Opening Unified Pod) 200 containing multiple semiconductor wafers, and transfers the FOUP 200 relative to a loading port (transfer section) 300, which is provided in a processing apparatus that performs various processes on the semiconductor wafers.

[0039] The bridge-type conveyor 1 includes a frame unit 2, a traveling unit 3, a transverse unit 4, a theta unit 5, a lifting drive unit 6, a lifting platform 7, and a controller 8. The frame unit 2 has a middle frame 21, a front frame 22, and a rear frame 23. The front frame 22 extends downward from the front end of the middle frame 21. The rear frame 23 extends downward from the rear end of the middle frame 21. Furthermore, "front" and "rear" refer to the front and rear sides in the traveling direction of the bridge-type conveyor 1, respectively.

[0040] The traveling unit 3 is positioned above the intermediate frame 21. The traveling unit 3 travels along the track 100, for example, by receiving power non-contactly from a high-frequency current line laid along the track 100. The lateral unit 4 is positioned below the intermediate frame 21. The lateral unit 4 causes the θ unit 5, the lifting drive unit 6, and the lifting platform 7 to move laterally (to the side of the traveling direction of the bridge-type transport vehicle 1). The θ unit 5 is positioned below the lateral unit 4. The θ unit 5 causes the lifting drive unit 6 and the lifting platform 7 to rotate in the horizontal plane.

[0041] The lifting drive unit 6 is located below the θ unit 5. The lifting drive unit 6 causes the lifting platform 7 to rise and fall. The lifting platform 7 is located below the lifting drive unit 6. The lifting platform 7 transfers the FOUP 200. The lifting platform 7 has a pair of clamping members (holding parts) 72 that hold the flange portion 201 of the FOUP 200. The pair of clamping members 72 are supported so that they can open and close in the horizontal direction. The pair of clamping members 72 are opened and closed by a drive motor (not shown) and a linkage mechanism (not shown). The controller 8 is located on the intermediate frame 21. The controller 8 is an electronic control unit consisting of a CPU, ROM, and RAM. The controller 8 controls various parts of the bridge conveyor 1.

[0042] The bridge conveyor 1, configured as described above, operates as follows: When transferring FOUP 200 from loading port 300 to bridge conveyor 1, bridge conveyor 1, without holding FOUP 200, stops above loading port 300. When the horizontal position of lifting platform 7 deviates from the position directly above loading port 300, the horizontal unit 4 and θ unit 5 are driven, thereby finely adjusting the horizontal position and angle of lifting platform 7 for each lifting drive unit 6. Next, lifting drive unit 6 lowers lifting platform 7, holding the flange 201 of FOUP 200 placed in loading port 300. Next, lifting drive unit 6 raises lifting platform 7 to the origin position (rising end), positioning FOUP 200 between front frame 22 and rear frame 23. Then, bridge conveyor 1, holding FOUP 200, begins to move.

[0043] On the other hand, when transferring FOUP 200 from bridge conveyor 1 towards loading port 300, bridge conveyor 1 holding FOUP 200 stops above loading port 300. If the horizontal position of lifting platform 7 (FOUP 200) deviates from its position directly above loading port 300, the horizontal unit 4 and θ unit 5 are driven, thereby fine-tuning the horizontal position and angle of lifting platform 7 for each lifting drive unit 6. Next, lifting drive unit 6 lowers lifting platform 7, loading FOUP 200 into loading port 300, and lifting platform 7 releases its holding on the flange 201 of FOUP 200. Next, lifting drive unit 6 raises lifting platform 7 to the rising end. Then, bridge conveyor 1, no longer holding FOUP 200, begins to move.

[0044] Next, the configuration of the lifting drive unit 6 will be explained. For example... Figure 1 as well as Figure 2 As shown, the lifting drive unit 6 includes a take-up roller 61, a motor 62, an encoder 63, a belt B, and idler rollers 65A and 65B.

[0045] The take-up rollers 61 are take-up drive units that take up or unwind the belt B individually by being driven by the motor 62. There are four take-up rollers 61 provided here. The motor 62 is the drive source for rotating each take-up roller 61. The motor 62 drives the four take-up rollers 61, for example, via a common rotating shaft (not shown).

[0046] Encoder 63 detects the rotational amount (drive amount) of motor 62. Encoder 63 outputs a count value related to the rotational amount of motor 62 to controller 8. Belt B is the suspension component for holding the lifting platform 7. There are four belts B. One end of each belt B is connected to the lifting platform 7. The other end of each belt B is connected to four take-up rollers 61 respectively. Idler rollers 65A and 65B guide the movement of belt B.

[0047] In this embodiment, the controller 8 controls the lifting amount of the lifting platform 7 by controlling the rotation amount of the take-up roller 61. The controller 8 performs the following first process: calculating the individual values ​​of the total length of the belt B, the individual value of the diameter of the take-up roller 61, and the individual value of the belt thickness as individual values ​​of the bridge conveyor 1. The rotation amount of the take-up roller 61 can be obtained based on the count value of the encoder 63.

[0048] In the first process, the lifting amount of the lifting platform 7 is approximated using a square function of the rotation amount of the take-up roller 61 (an error correction function based on the least squares method), thereby calculating the individual values ​​of the total length of belt B, the diameter of the take-up roller 61, and the thickness of belt B. This square function includes the individual values ​​of the total length of belt B, the diameter of the take-up roller 61, and the thickness of belt B as coefficients. In the first process, the individual values ​​of the total length of belt B, the diameter of the take-up roller 61, and the thickness of belt B are calculated based on a data set containing two or more sampled data points. This sampled data consists of the lifting amount of the lifting platform 7 and the rotation amount of the take-up roller 61 during that lifting amount.

[0049] First, the principle of the first process will be explained. The basic calculation formula for the lifting amount of the lifting platform 7 is as follows (8), which can be rearranged to be expressed by the following formula (9).

[0050]

Formula 3

[0051] L=L0-π(D(n0-n)+t(n0-n) 2 )…(8)

[0052] L=(-πt)n 2 +(π(D+2tn0))n+(L0-πn0(D+tn0))…(9)

[0053] Wherein, L: the lifting amount of the lifting platform 7, n: the rotation amount of the winding drum 61, t: the individual value of the thickness of the band B, D: the individual value of the diameter of the winding drum 61, L0: the individual value of the total length of the band B, and n0: the rotation amount of the winding drum 61 when the lifting platform 7 is at the origin position.

[0054] According to the above formula (8), when parameters A, B, and C are set as the following formulas (10) to (12), the lifting amount L of the lifting platform 7 can be expressed as the following formula (13). In addition, when the rotation amount n of the winding drum 61 is 0, the lifting amount L of the lifting platform 7 is 0, so parameter C = 0 is valid.

[0055]

Formula 4

[0056] -πt=A…(10)

[0057] π(D+2tn0)=B…(11)

[0058] L0-πn0(D+tn0)=C…(12)

[0059] L = An 2 +Bn+C…(13)

[0060] When the number of samples obtained is set to N (an integer greater than 2), the sum of the data set of the approximation function and the squared error S can be expressed by the following equation (14). At this time, in order to find the parameters A and B that minimize the error, δS / δA = 0 and δS / δB = 0 as shown in the following equation (15).

[0061]

Formula 5

[0062]

[0063]

[0064]

[0065]

[0066] Based on the simultaneous equations of equations (16) and (17), parameters A and B are obtained as shown in equations (18) to (23). Therefore, it can be seen that the individual value t of the thickness of belt B and the individual value D of the diameter of the winding roller 61 can be calculated based on the results of parameters A and B. Furthermore, it can be seen that by substituting the individual value t of the thickness of belt B and the individual value D of the diameter of the winding roller 61 into parameter C (refer to equation (12) above), the individual value L0 of the total length of belt B can be calculated.

[0067]

Formula 6

[0068]

[0069]

[0070]

[0071]

[0072]

[0073]

[0074]

[0075]

[0076] Where, t: individual value of the thickness of band B, D: individual value of the diameter of take-up drum 61, L0: individual value of the total length of band B, n0: rotation amount of take-up drum 61 when the lifting platform 7 is at the origin position, N: number of samples (an integer greater than 2), n i L represents the rotation amount of the take-up roller 61 in the i-th sample. i : The lifting amount of the lifting platform 7 in the i-th sample.

[0077] Therefore, in this embodiment, in the first process, based on the above formulas (10) to (13), (22), and (23), the individual value L0 of the total length of belt B, the individual value D of the diameter of the winding roller 61, and the individual value t of the thickness of belt B are calculated.

[0078] The controller 8, upon receiving the lifting amount L of the lifting platform 7, performs the following second process: based on the individual value L0 of the total length of the belt B, the individual value D of the diameter of the take-up roller 61, and the individual value t of the thickness of the belt B calculated in the first process, it calculates the rotation amount of the take-up roller 61 relative to the lifting amount L. In the second process, based on the above formula (8), the rotation amount of the take-up roller 61 relative to the lifting amount L of the lifting platform 7 is calculated. Then, the controller 8 controls the drive of the motor 62 based on the rotation amount of the take-up roller 61 calculated in the second process, so that the lifting platform 7 is raised to the desired height position (e.g., the height position at which the lifting platform 7 holds the FOUP 200 of the loading port 300 and the height position at which the lifting platform 7 places the FOUP 200 into the loading port 300).

[0079] The controller 8 performs the following process to obtain the rotation amount n0 of the winding drum 61 when the lifting platform 7 is at the origin position. That is, the controller 8 first performs the following process: Figure 3 As shown in (a), drive motor 62 to pull the entire belt B out of take-up roller 61, and obtain the rotation amount of take-up roller 61 at this time (the count value of encoder 63) as the first rotation amount. Then, controller 8... Figure 3 As shown in (b), the drive motor 62 is used to wind the tape B onto the take-up roller 61 until the lifting platform 7 is at the origin position, and the rotation amount of the take-up roller 61 at this time (the count value of the encoder 63) is obtained as the second rotation amount. Then, the controller 8 obtains the value obtained by subtracting the second rotation amount from the first rotation amount as the rotation amount n0 of the take-up roller 61 when the lifting platform 7 is at the origin position.

[0080] Controller 8 acquires a data set containing sampled data from the first to the Nth samples by performing data acquisition processing from the first to the third samples. The i-th sampled data (i is an integer from 1 to N) is obtained by the rotation amount n of the take-up roller 61 in the i-th sample. i The lifting amount L of the lifting platform 7 in the i-th sample i The data constitutes the data. The following section provides a detailed explanation of the processing methods used to obtain data 1 through 3.

[0081] like Figure 4As shown in (a), firstly, the lifting platform 7 holds the first measuring component 11, and the second measuring component 12 is positioned directly below the first measuring component 11 on the ground 31. The first measuring component 11 has a flange portion held by a pair of clamping members 72. The lower surface of the first measuring component 11 has a flat surface. The second measuring component 12 forms a base placed on the ground 31. The upper surface of the second measuring component 12 has a flat surface. A sensor 81 is provided on the second measuring component 12. The sensor 81 is a sensor that detects the distance between the first measuring component 11 and the second measuring component 12. For example, a laser rangefinder emitting a laser L1 is used as the sensor 81. The sensor 81 sends data related to the detected distance to the controller 8.

[0082] The controller 8 performs the first data acquisition process. In the first data acquisition process, the motor 62 is controlled to make the take-up roller 61 rotate by an amount n0 so that the lifting platform 7 is located at the origin position. In this state, the distance between the first measuring component 11 and the second measuring component 12 detected by the sensor 81 is obtained as the first distance.

[0083] Next, the second data acquisition process is executed via controller 8. In the second data acquisition process, such as... Figure 4 As shown in (b), when the lifting platform 7 has been raised or lowered by a set amount, the distance detected by the sensor 81 is obtained as the second distance, and the value obtained by subtracting the first distance from the second distance, along with the rotation amount of the winding roller 61 at the set amount of raising or lowering, are obtained as the raising or lowering amount of the lifting platform 7 and the rotation amount of the winding roller 61 in the first sampled data. Then, the controller executes the third data acquisition process. In the third data acquisition process, the set amount of raising or lowering is changed and the second data acquisition process is executed repeatedly (N-1 times). Thus, the first to Nth sampled data are obtained. Here, N is 4.

[0084] like Figure 2 As shown, the bridge-type conveyor 1 includes an input unit 9, which can input multiple sets of second data to obtain the set lifting and lowering amounts for processing. The input unit 9 is not particularly limited; for example, it can be a communication device that inputs the set lifting and lowering amounts from the outside via communication, or a touch panel that inputs the set lifting and lowering amounts via touch operation.

[0085] In the bridge conveyor 1, the individual values ​​L0 of the total length of belt B, D of the diameter of the winding roller 61, and t of the thickness of belt B are calculated. Based on these individual values, the rotation amount of the winding roller 61 relative to the lifting amount of the lifting platform 7 is calculated. Therefore, the rotation amount of the winding roller 61 relative to the lifting amount of the lifting platform 7 can be determined by fully considering the individual differences in the bridge conveyor 1. Thus, even when there are individual differences in the bridge conveyor 1, the lifting platform 7 can be reliably raised and lowered to the desired height.

[0086] Through intensive research, the inventors discovered that the lifting amount of the lifting platform 7 can be approximated by a square function of the rotation amount of the winding roller 61. This square function includes, as coefficients, the individual value L0 of the total length of belt B, the individual value D of the diameter of the winding roller 61, and the individual value t of the thickness of belt B. Therefore, in the bridge conveyor 1, during the first process, this approximation is used to calculate the individual value L0 of the total length of belt B, the individual value D of the diameter of the winding roller 61, and the individual value t of the thickness of belt B. Thus, these individual values ​​can be obtained simply and accurately.

[0087] In the bridge-type conveyor 1, in the first process, based on a data set containing two or more sampled data points, the individual value L0 of the total length of belt B, the individual value D of the diameter of the winding roller 61, and the individual value t of the thickness of belt B are calculated. This sampled data consists of the lifting amount of the lifting platform 7 and the rotation amount of the winding roller 61 during that lifting amount. Thus, these individual values ​​can be easily and accurately obtained using the data set.

[0088] In the bridge-type conveyor 1, in the first process, based on the above formulas (10) to (13), (22), and (23), the individual value L0 of the total length of belt B, the individual value D of the diameter of the winding roller 61, and the individual value t of the thickness of belt B are calculated. Thus, the individual value L0 of the total length of belt B, the individual value D of the diameter of the winding roller 61, and the individual value t of the thickness of belt B can be calculated more simply and accurately.

[0089] In the bridge conveyor 1, the controller 8 performs: a first data acquisition process, in which the distance detected by the sensor 81 is acquired as a first distance while the lifting platform 7 is at the origin position; a second data acquisition process, in which the distance detected by the sensor 81 is acquired as a second distance while the lifting platform 7 is raised or lowered by a set amount, and the value obtained by subtracting the first distance from the second distance and the rotation amount of the winding roller 61 at the set amount of raising or lowering are acquired as sample data; and a third data acquisition process, in which the second data acquisition process is repeatedly executed while changing the set amount of raising or lowering. Thus, at least two sample data points can be automatically acquired.

[0090] The bridge-type conveyor 1 is equipped with an input unit 9 that can input multiple second data points to obtain and process the set lifting and lowering amounts for each. In this case, each set lifting and lowering amount can be appropriately input via the input unit 9.

[0091] In the bridge-type conveyor 1, in the second process, the rotation amount of the take-up roller 61 relative to the lifting amount of the lifting platform 7 is calculated based on the above formula (8). Thus, the rotation amount of the take-up roller 61 relative to the lifting amount of the lifting platform 7 can be calculated simply and accurately.

[0092] In the bridge-type conveyor 1 configured as described above, the following method is used to calculate the rotation amount of the winding roller 61. Specifically, as individual values ​​for the bridge-type conveyor 1, the individual value L0 of the total length of belt B, the individual value D of the diameter of the winding roller 61, and the individual value t of the thickness of belt B are calculated (step 1). Next, based on the calculated individual value L0 of the total length of belt B, the individual value D of the diameter of the winding roller 61, and the individual value t of the thickness of belt B, the rotation amount of the winding roller 61 relative to the lifting amount of the lifting platform 7 is calculated (step 2).

[0093] In the method for calculating the rotation amount of the winding roller 61 in the bridge conveyor 1, the individual values ​​L0 of the total length of belt B, D of the diameter of the winding roller 61, and t of the thickness of belt B are also calculated. Based on these individual values, the rotation amount of the winding roller 61 relative to the lifting amount of the lifting platform 7 is calculated. Therefore, the rotation amount of the winding roller 61 relative to the lifting amount of the lifting platform 7 can be determined by fully taking into account the individual differences of the bridge conveyor 1. Thus, even when there are individual differences in the bridge conveyor 1, the lifting platform 7 can be reliably raised and lowered to the desired height position.

[0094] Figure 5 This is a graph showing the error in the lifting amount of the lifting platform 7 relative to the rotation amount of the take-up roller 61. The horizontal axis represents the rotation amount of the take-up roller 61 (the count value of the encoder 63). The vertical axis represents the error (mm) between the measured value and the calculated value related to the lifting amount of the lifting platform 7. In the figure, Q1 is the evaluation result of the embodiment, and Q2 is the evaluation result of the comparative example. The embodiment corresponds to the bridge conveyor 1 of this embodiment. The comparative example corresponds to a conventional bridge conveyor that uses a general method for calculating the rotation amount of the take-up roller 61 (a method for calculating the rotation amount by setting the total length of belt B, the diameter of the take-up roller 61, and the thickness of belt B as fixed values).

[0095] like Figure 5As shown, it can be seen that the error in the lifting amount of the lifting platform 7 can be suppressed in the embodiment. Therefore, it can be seen that the lifting platform 7 can be reliably raised and lowered to the desired height position in the embodiment. In addition, it can be seen that the error in the lifting amount of the lifting platform 7 is relatively large in the comparative example, especially as the rotation amount of the take-up roller 61 increases, the error increases according to a square function.

[0096] The embodiments of the present invention have been described above, but the present invention is not limited to the above embodiments. Various modifications can be made to the above embodiments without departing from the spirit of the invention.

[0097] like Figure 6 As shown, in the data acquisition processes of the first to third stages, the lifting platform 7 can hold the first measuring component 91, and the second measuring component 92 can be positioned directly below the first measuring component 91 on the ground 31. In this case, a sensor 82 for detecting the distance between the first measuring component 91 and the second measuring component 92 can be installed at the lower part of the first measuring component 91. For example, a laser rangefinder emitting a laser L2 can be used as the sensor 82.

[0098] In the above embodiment, sampling data is automatically acquired through the first to third data acquisition processes, but this is not a limitation. Sampling data can also be acquired through user input or through external communication. Similarly, the rotation amount n0 of the winding roller 61 when the lifting platform 7 is at the origin position can also be acquired through user input or through external communication. In the above embodiment, the lifting platform 7 can also be suspended by three or five or more belts B.

[0099] In the above embodiments, based on the above equations (10) to (13), (22), and (23), the individual value L0 of the total length of belt B, the individual value D of the diameter of the winding roller 61, and the individual value t of the thickness of belt B are calculated, but it is not limited to these. Different approximation functions than the above equations (10) to (13), (22), and (23) can also be used to calculate the individual value L0 of the total length of belt B, the individual value D of the diameter of the winding roller 61, and the individual value t of the thickness of belt B.

[0100] The configurations of the above-described embodiments and modifications are not limited to the materials and shapes described above, and various materials and shapes can be used. The configurations of the above-described embodiments or modifications can be arbitrarily applied to the configurations of other embodiments or modifications. A portion of the configurations of the above-described embodiments or modifications may also be appropriately omitted without departing from the spirit of one aspect of the invention.

Claims

1. A bridge-type conveyor vehicle, comprising a lifting platform for transferring goods, a take-up roller for overlapping and winding a lifting member mounted on the lifting platform, and a controller for controlling the lifting amount of the lifting platform by controlling the rotation amount of the take-up roller, wherein, The above controller executes: The first process involves calculating, as individual values ​​for the bridge-type conveyor, the individual values ​​for the total length of the lifting member, the individual value for the diameter of the winding drum, and the individual value for the thickness of the lifting member. as well as The second process involves calculating the rotation amount of the winding drum relative to the lifting amount of the lifting platform, based on the individual values ​​of the total length of the lifting member, the diameter of the winding drum, and the thickness of the lifting member calculated in the first process. In the first process described above, the lifting amount of the lifting platform is approximated by the square function of the rotation amount of the winding drum, thereby calculating the individual values ​​of the total length of the lifting member, the diameter of the winding drum, and the thickness of the lifting member. The square function includes the individual values ​​of the total length of the lifting member, the diameter of the winding drum, and the thickness of the lifting member as coefficients.

2. The bridge-type conveyor vehicle according to claim 1, wherein, In the first process described above, based on a data set containing two or more sampled data, the individual values ​​of the total length of the lifting member, the individual value of the diameter of the winding drum, and the individual value of the thickness of the lifting member are calculated. The sampled data consists of the lifting amount of the lifting platform and the rotation amount of the winding drum during the lifting amount.

3. The bridge-type conveyor vehicle according to claim 2, wherein, In the first process described above, based on the following formulas (1) to (6), the individual values ​​of the total length of the lifting member, the individual value of the diameter of the winding drum, and the individual value of the thickness of the lifting member are calculated. 【Formula 1】 Where, L: the lifting amount of the lifting platform, n: the rotation amount of the winding drum, t: the individual value of the thickness of the lifting member, D: the individual value of the diameter of the winding drum, L0: the individual value of the total length of the lifting member, n0: the rotation amount of the winding drum when the lifting platform is at the origin position, N: an integer with a sampling quantity of 2 or more, n i L represents the rotation amount of the take-up roller in the i-th sample. i : The lifting amount of the aforementioned lifting platform in the i-th sample.

4. The bridge-type conveyor vehicle according to claim 2 or 3, wherein, The above controller executes: The first data acquisition process, with the lifting platform at the origin position, acquires the distance detected by the sensor as the first distance. The sensor detects the distance between the first measuring component held by the lifting platform and the second measuring component disposed directly below the first measuring component. The second data acquisition process, while the lifting platform has been raised or lowered by a set amount, acquires the distance detected by the sensor as a second distance, and acquires the value obtained by subtracting the first distance from the second distance, along with the rotation amount of the take-up roller at the set amount of raising or lowering, as the lifting amount of the lifting platform and the rotation amount of the take-up roller in the sampled data; and The third data acquisition process involves repeatedly executing the second data acquisition process by changing the set increment or decrement amount.

5. The bridge-type conveyor vehicle according to claim 4, wherein, It has an input section that can input the second data multiple times to obtain the set increase or decrease amount for each of the above-mentioned processing.

6. The bridge-type conveyor vehicle according to claim 1, wherein, In the second process described above, the rotation amount of the take-up roller relative to the lifting amount of the lifting platform is calculated based on the following formula (7). 【Formula 2】 Wherein, L: the lifting amount of the lifting platform, n: the rotation amount of the winding drum, t: the individual value of the thickness of the lifting member, D: the individual value of the diameter of the winding drum, L0: the individual value of the total length of the lifting member, and n0: the rotation amount of the winding drum when the lifting platform is at the origin position.

7. A method for calculating the rotation amount of a winding drum in a bridge conveyor, wherein the method calculates the rotation amount of the winding drum in the bridge conveyor, the bridge conveyor comprising a lifting platform for transferring goods, a winding drum for overlapping and winding a lifting member installed on the lifting platform, and a controller for controlling the lifting amount of the lifting platform by controlling the rotation amount of the winding drum, comprising: Step 1: As individual values ​​for the aforementioned bridge-type conveyor, calculate the individual values ​​for the total length of the aforementioned lifting member, the individual value for the diameter of the aforementioned winding drum, and the individual value for the thickness of the aforementioned lifting member. as well as Step 2: Based on the individual values ​​of the total length of the lifting member, the diameter of the winding drum, and the thickness of the lifting member calculated in Step 1 above, calculate the rotation amount of the winding drum relative to the lifting amount of the lifting platform. In the first step above, the lifting amount of the lifting platform is approximated by the square function of the rotation amount of the winding drum, thereby calculating the individual values ​​of the total length of the lifting member, the diameter of the winding drum, and the thickness of the lifting member. The square function includes the individual values ​​of the total length of the lifting member, the diameter of the winding drum, and the thickness of the lifting member as coefficients.

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