Driver unit and signal generation module

Abstract

We provide a driver unit that achieves the desired specifications simply by designing the control board. [Solution] A driver unit that generates a drive signal for a piezoelectric motor based on a control signal generated by a control board, comprising a housing configured to allow the control board to be attached and detached, and a signal generation module that can be attached and detached to the housing, wherein the signal generation module has an amplification unit that amplifies the control signal to generate an electrical signal, a signal generation unit that generates a drive signal from the electrical signal, and a module board to which the amplification unit and the signal generation unit are fixed.

Description

Technical Field

[0001] The present invention relates to a driver unit and a signal generation module that generate drive signals for a piezoelectric motor.

Background Art

[0002] As a driving device for an ultrasonic motor, which is an example of a piezoelectric motor, Patent Document 1 describes an ultrasonic motor driving device that supplies an alternating current signal to a vibrating body constituting the ultrasonic motor. This ultrasonic motor driving device includes an oscillator, a distributor, and a transformer.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] When creating a driver unit for a piezoelectric motor, it is necessary to design a control board that generates a control signal for generating a drive signal. Also, in order to drive a piezoelectric motor, it is necessary to amplify the control signal to generate a pseudo-alternating current signal. Therefore, it is further necessary to design a signal generation circuit having a signal amplification unit that amplifies the control signal and a drive signal generation unit that generates a drive signal. Here, since the design of the control board is relatively easy, a user who purchases a piezoelectric motor from a supplier can also design the control board by themselves.

[0005] On the other hand, designing signal generation circuits requires expertise, making it difficult for users to design them themselves. Therefore, if a user desires a driver unit that meets their specific requirements, they need to have a supplier manufacture it. In other words, the user needs a supplier to design the signal generation circuit and then manufacture a driver unit incorporating that circuit. For this reason, there is a need for a means for users themselves to create a driver unit that meets their desired specifications. [Means for solving the problem]

[0006] A driver unit according to one embodiment is a driver unit that generates a drive signal for a piezoelectric motor based on a control signal generated by a control board, The housing is configured to allow the control board to be attached and detached, The housing is equipped with a detachable signal generation module, The signal generation module includes an amplification unit that amplifies the control signal to generate an electrical signal, a signal generation unit that generates the drive signal from the electrical signal, and a module board on which the amplification unit and the signal generation unit are fixed.

[0007] Furthermore, another signal generation module according to a different embodiment is a signal generation module that generates a drive signal for a piezoelectric motor based on a control signal generated by a control board, The system includes an amplification unit that amplifies the control signal to generate an electrical signal, a signal generation unit that generates the drive signal from the electrical signal, and a module board on which the amplification unit and the signal generation unit are fixed. [Brief explanation of the drawing]

[0008] [Figure 1] This is an explanatory diagram illustrating the generation of drive signals. [Figure 2] This is a schematic perspective view of the driver unit. [Figure 3] This is a schematic perspective view of the driver unit with the casing cover removed. [Figure 4] This is a schematic overview of the module. [Figure 5] This is a schematic perspective view of the module with the drive signal generation unit omitted. [Figure 6] This is a schematic perspective view of the module with the drive signal generation unit and fixing members omitted. [Figure 7] This is a schematic perspective view of the enclosure circuit board. [Figure 8] This is a schematic perspective view of the driver unit with the housing lid and central housing section omitted. [Figure 9] This is a schematic perspective view of the control board. [Figure 10] This is a plan view showing the driver unit with the housing cover removed. [Figure 11] A shows the heat sink of the first modified example, and B shows the heat sink of the second modified example. [Modes for carrying out the invention]

[0009] Hereinafter, exemplary embodiments for carrying out the present invention will be described in detail with reference to the drawings. However, the dimensions, materials, shapes, and relative positions of components described in the following embodiments can be arbitrarily set and modified according to the configuration of the apparatus or method to which the present invention is applied, or according to various conditions. Furthermore, unless otherwise specified, the scope of the present invention is not limited to the embodiments specifically described below.

[0010] In this specification, the side of the driver unit 100 on which the connection ports are provided is the front, and the opposite side is the rear. Also, "up and down" corresponds to the upward and downward directions in the direction of gravity, respectively. Furthermore, "substrate" means a material for mounting electronic components and performing wiring, and includes printed circuit boards or electronic circuit boards, etc. In addition, other substrates or electrical components mounted on the driver unit 100 may be interposed in the transmission and reception of signals between substrates, or in the transmission and reception of signals from external equipment 93 to each substrate.

[0011] [Driver Unit] Referring to Figure 1, we will describe the control board 21 that generates the control signal S1 which is the basis for the drive signal S3, and the driver unit 100 that generates the drive signal S3 for the piezoelectric motor 90 based on the generated control signal S1. Figure 1 is an explanatory diagram for illustrating the control by the driver unit 100. Also, the arrows in Figure 1 indicate the output or input of a signal.

[0012] As shown in Figure 1, the driver unit 100 is connected to the piezoelectric motor 90, the encoder 91, and the power supply 92. For example, the driver unit 100 is connected to the piezoelectric motor 90 via a motor cable. The driver unit 100 is also connected to the encoder 91 via an encoder cable. The driver unit 100 is also connected to the power supply 92 via a power cable. For example, the power supply 92 is a DC power supply that outputs a DC voltage.

[0013] Furthermore, the driver unit 100 is connected to an external device 93 (for example, a personal computer or a control device with a control circuit) by wire or wireless connection. For example, the driver unit 100 is connected to the external device 93 via a connection cable. As another example, the driver unit 100 is connected to the external device 93 via a USB cable (for example, a Type B USB cable). The driver unit 100 then controls the rotation direction, rotation speed, rotation angle, and rotation position of the piezoelectric motor 90 based on signals input from the external device 93.

[0014] Furthermore, the driver unit 100 includes a module 10 which is a signal generation module detachable from the housing 30 shown in FIG. 2. This module 10 is attached to the housing 30 directly or indirectly. Also, the module 10 has a signal amplification unit 12 which is an example of an amplification unit that amplifies the control signal S1 generated by the control board 21 to generate an electrical signal S2. Also, the module 10 has a drive signal generation unit 13 which is an example of a signal generation unit that further amplifies the generated electrical signal S2 and generates a drive signal S3 from the amplified electrical signal S2. Furthermore, as shown in FIG. 4, the module 10 has a module board 16 to which the signal amplification unit 12 and the drive signal generation unit 13 are fixed. These signal amplification unit 12 and drive signal generation unit 13 are fixed to the module board 16 directly or indirectly.

[0015] For example, the control board 21 generates control signals S1 consisting of rectangular waves, and generates a plurality of types of control signals S1 with phases shifted from each other. Also, the rotation speed information, rotation angle information, and rotation position information of the piezoelectric motor 90 detected by the encoder 91 are fed back to the control board 21. Then, the control board 21 performs feedback control of the piezoelectric motor 90. As an example, the control board 21 has a processor 23 (FIG. 9) such as a CPU (Central Processing Unit) or MPU (Micro-Processing Unit), and generates a control signal S1 having a voltage of about 3V to 5V. Also, the control board 21 may be an integrated circuit such as an ASIC (Application Specific Integrated Circuit) or an FPGA (Field Programmable Gate Array).

[0016] The control signal S1 generated and output by the control board 21 is input to the signal amplification unit 12. Then, the signal amplification unit 12 amplifies the control signal S1. As an example, the signal amplification unit 12 is a FET (Field effect transistor), and amplifies the control signal S1 until the voltage reaches about 20V to 25V. Then, the signal amplification unit 12 outputs the amplified electrical signal S2.

[0017] The electrical signal S2 generated by amplification in the signal amplification unit 12 is input to the drive signal generation unit 13. Then, the drive signal generation unit 13 amplifies the electrical signal S2. As an example, the drive signal generation unit13 amplifies the electrical signal S2 until it reaches a voltage of about100V, more preferably a voltage of about360V to 400V. Then, the drive signal generation unit 13 generates a drive signal S3 which is a pseudo AC signal (hereinafter also referred to as an AC signal) from the amplified electrical signal S2. This AC signal includes a positive component and a negative component. As an example, the drive signal generation unit 13 is a transformer and generates an AC signal composed of two sine waves (that is, sine wave and cosine wave) whose phases are shifted by about 80 degrees to 90 degrees. Then, the piezoelectric motor 90 is driven by inputting the drive signal S3 generated by the drive signal generation unit 13 and the ground signal sent from the control board 21 into the piezoelectric motor 90.

[0018] [[ID=******]] When driving the piezoelectric motor 90 that outputs a particularly high torque driving force, the amplitude difference from the peak of the positive component to the peak of the negative component in the AC signal is increased. Therefore, the drive signal generation unit 13 amplifies the voltage of the electrical signal S2 generated by the signal amplification unit 12 to about 8 to 10 times. Then, the drive signal generation unit 13 generates the drive signal S3 based on the amplified electrical signal S2. Here, it is desirable for the drive signal generation unit 13 to generate an AC signal with a smooth waveform. Therefore, proficiency is required in the design of the signal generation circuit including the signal amplification unit 12 and the drive signal generation unit 13. On the other hand, the design of the control board 21 is relatively easy.

[0019] Therefore, the driver unit 100 includes a module 10 which is a signal generation circuit including a signal amplification unit 12 and a drive signal generation unit 13. This module 10 is configured by modularizing the signal amplification unit 12 and the drive signal generation unit 13. As a result, the user can design a driver unit 100 that achieves the desired specifications simply by designing the control board 21. In other words, according to the driver unit 100 of this embodiment, the desired specifications of the driver unit 100 can be achieved simply by designing the control board 21. As an example, the desired specifications may be a specification that employs a different type of processor 23 than existing ones, or a specification that employs memory with a larger capacity.

[0020] Here, we will briefly explain the piezoelectric motor 90. As an example, the piezoelectric motor 90 comprises a roughly plate-shaped base and a case screwed to the base. Furthermore, the piezoelectric motor 90 has an output shaft that penetrates the base and case and protrudes from the base and case. The piezoelectric motor 90 also comprises a stator and a rotor, which is the driven part. The stator is fixed to the base, and the rotor faces the stator. The stator and rotor are housed in a space inside the case.

[0021] The stator also includes a piezoelectric element, an elastic body, and a sliding material. The piezoelectric element and sliding material are attached to the elastic body. The rotor also has an annular member. This annular member has a base portion that contacts the sliding material and a disc spring portion that is integrally formed with the base portion. When a drive signal S3 is applied to the piezoelectric motor 90, the expansion and contraction of the piezoelectric element causes deflection vibration in the elastic body, generating a traveling wave in the circumferential direction. At each peak of this traveling wave, the rotor is in contact with the elastic body via the sliding material. Each peak undergoes elliptical motion, and the trajectory of this elliptical motion is in the opposite direction to the direction of the traveling wave. Therefore, the rotor rotates in the opposite direction to the traveling wave. As a result, the output shaft rotates in the same direction as the rotor as the rotor rotates.

[0022] [Driver Unit Structure] Next, the structure of the driver unit 100 will be described with reference to Figures 2 and 3. Figure 2 shows the driver unit 100 viewed from the front and above. Figure 3 shows the inside of the driver unit 100 with the housing cover 33 removed. Note that in Figure 3, the fins 11F of one of the two modules 10 are not shown.

[0023] As shown in Figure 2, the driver unit 100 has an output port 101 to which a motor cable is connected for connection to the piezoelectric motor 90. The driver unit 100 also has an input port 102 to which an encoder cable is connected for connection to the encoder 91. Furthermore, the driver unit 100 has an input / output port 103 to which a connection cable is connected for connection to an external device 93, and a USB port 104 to which a USB cable is connected. In addition, the driver unit 100 has a power port 105 to which a power cable is connected for connection to a power supply 92.

[0024] Furthermore, the driver unit 100 can control multiple piezoelectric motors 90, and in the example shown in Figure 2, it can control two piezoelectric motors 90. Therefore, there are two output ports 101, two input ports 102, and two input / output ports 103. Alternatively, the driver unit 100 may control one or more piezoelectric motors 90. In this case, the driver unit 100 has a number of output ports 101, input ports 102, and input / output ports 103 corresponding to the number of piezoelectric motors 90 to be controlled.

[0025] The driver unit 100 also includes a housing 30 that houses the control board 21 and the module 10. For example, the housing 30 has a plate-shaped front housing portion 31 and a rear housing portion 32, and a housing lid portion 33. The housing 30 also has a central housing portion 34 located between the front housing portion 31 and the rear housing portion 32, which has a substantially U-shaped cross-section along the vertical direction. The front housing portion 31 and the rear housing portion 32 and the housing lid portion 33 are screwed to the central housing portion 34. As a result, in Figure 2, the housing 30 has a substantially rectangular parallelepiped shape. However, the housing 30 may have other shapes such as a cylinder or a rectangular tube. In addition, the parts constituting the housing 30 may be fixed to each other by methods other than screwing, such as welding or adhesive.

[0026] As shown in Figure 3, the housing 30 can accommodate a control board 21 and multiple modules 10. Here, the number of modules 10 accommodated corresponds to the number of piezoelectric motors 90 to be controlled. In the example in Figure 3, one control board 21 and two modules 10 are housed in the housing 30. However, there may be two or more control boards 21, and there may be one or three or more modules 10. Furthermore, the control board 21 is mounted on the modules 10 in an upright position. That is, the direction in which the surface of the mounted control board 21 extends (i.e., the direction perpendicular to the thickness direction) is perpendicular to the mounting surface of the control board 21. This allows for effective use of the space inside the housing 30.

[0027] Module 10 has a cooling fan 11, which faces heat dissipation fins 11F. The cooling fan 11 is exposed to the outside of the housing 30 through a hole 32H formed in the rear part 32 of the housing. This allows the housing 30 to be made smaller compared to when the cooling fan 11 is placed inside the housing 30. Note that the fins 11F of module 10 located on the upper side in Figure 3 are omitted from the illustration in order to show the hole 32H.

[0028] [Signal generation module] Next, the module 10 will be described with reference to Figures 4 to 8. Figures 4 to 6 show the module 10 as viewed from the front and above. Note that the drive signal generation unit 13 is not shown in Figure 5. Also, the drive signal generation unit 13 and the fixing member 15 are not shown in Figure 6. Figure 7 is a schematic perspective view of the housing substrate 41 to which the module substrate 16 is fixed. Note that in Figure 7, in addition to the housing substrate 41, the rear part 32 of the housing 30 is also shown. Figure 8 is a schematic perspective view showing the inside of the driver unit 100. Note that in Figure 8, the housing lid 33 and the central part 34 of the housing, and the fin 11F of one of the modules 10 are not shown.

[0029] As shown in Figure 4, module 10 has a signal amplification unit 12 and a drive signal generation unit 13. In the example in Figure 4, module 10 has four signal amplification units 12 and two drive signal generation units 13. However, the number of signal amplification units 12 may be three or fewer or five or more. Also, the number of drive signal generation units 13 may be one or three or more. Module 10 also has a heat sink 14 and a cooling fan 11. This allows each module 10 to be cooled. Furthermore, module 10 has a fixing member 15 for fixing the signal amplification units 12 to the heat sink 14 and fins 11F.

[0030] The heat sink 14 is a metal member having a roughly L-shaped horizontal cross-section. Alternatively, the heat sink 14 may be formed by combining multiple members to achieve a roughly L-shape. Furthermore, the heat sink 14 may have other shapes, such as a roughly U-shaped horizontal cross-section. The cooling fan 11 and fins 11F are fixed to the heat sink 14 by screws inserted from the rear of the cooling fan 11, so as to sandwich the heat sink 14. Alternatively, the cooling fan 11 may be separate from the module 10. For example, the cooling fan 11 may be mounted on the housing 30 so as to face the fins 11F. Alternatively, the fins 11F may be integrally formed with the heat sink 14.

[0031] Furthermore, module 10 has a module board 16. For example, the module board 16 is an IC board. The module board 16 has module terminals 16A for signal input and output. These module terminals 16A protrude downwards. In addition, the signal amplification unit 12 and the drive signal generation unit 13 are electrically connected to the module board 16. A heat sink 14 is also screwed to the module board 16. Thus, module 10 is modularized to include the signal amplification unit 12 and the drive signal generation unit 13, a cooling fan 11, fins 11F, and a heat sink 14.

[0032] Alternatively, each component of module 10 may be fixed to the module board 16 by means other than screws, such as adhesive or soldering. Furthermore, the module terminal 16A may be either a male or female terminal.

[0033] In module 10, each electronic component is arranged along the longitudinal direction of the module substrate 16. Specifically, module 10 has multiple drive signal generation units 13 and multiple signal amplification units 12. The direction in which the multiple drive signal generation units 13 are arranged and the direction in which the multiple signal amplification units 12 are arranged are the same. For example, two drive signal generation units 13 are arranged along the longitudinal direction of the module substrate 16. Similarly, four signal amplification units 12 are also arranged along the longitudinal direction of the module substrate 16. This allows module 10 to have a long, narrow shape. Therefore, the internal space of the housing 30 can be used effectively. For example, when adding modules 10, no wasted space is created compared to when module 10 has a roughly square shape. However, module 10 may have a roughly square shape.

[0034] As shown in Figure 5, the fixing member 15 is a roughly rectangular parallelepiped-shaped metal member. The fixing member 15 is in contact with the signal amplification unit 12 and functions to dissipate heat transferred from the signal amplification unit 12. The signal amplification unit 12 is fixed to the fixing member 15 by screws that pass through the signal amplification unit 12 from the back side of the heat sink 14. Furthermore, the fixing member 15 is fixed to the heat sink 14 by these screws. In Figure 5, only two of the four signal amplification units 12 are screwed in, but all of the signal amplification units 12 may be screwed in. In addition, a screw (for example, made of resin) is inserted into the approximate center of the fixing member 15. The temperature sensor 17 is pressed against the heat sink 14 by this screw.

[0035] To drive the piezoelectric motor 90, it is necessary to generate an AC signal with a large amplitude difference. Therefore, amplification by the signal amplification unit 12 and the drive signal generation unit 13, which are heat-generating devices, is required. Furthermore, to suppress the temperature rise of module 10, module 10 needs to be cooled. For this reason, a temperature sensor 17, as shown in Figure 6, is provided on each module 10. The temperature sensor 17 contacts the heat sink 14 to detect the temperature of the heat sink 14. The temperature sensor 17 is positioned between multiple signal amplification units 12 that are lined up side by side. In other words, the heat sink 14 is sandwiched between pairs of signal amplification units 12. This suppresses the uneven detection of the heat influence of multiple signal amplification units 12, and the heat sink 14 can detect the temperature with higher accuracy.

[0036] The temperature sensor 17 transmits a temperature signal corresponding to the detected temperature to the control board 21. Since this temperature sensor 17 is provided in each module 10, the control board 21 can manage the temperature of each of the multiple modules 10. Therefore, the control board 21 can manage the temperature of only the module 10 that is currently in use among the multiple modules 10. For example, when the temperature indicated by the temperature signal output by the temperature sensor 17 exceeds a threshold, the control board 21 stops the rotation of the piezoelectric motor 90. Alternatively, the control board 21 may control the piezoelectric motor 90 to increase the rotation speed by lowering the frequency of the drive signal S3. Alternatively, the control board 21 may intermittently increase or decrease the frequency of the drive signal S3.

[0037] The module board 16 has module mounting holes 16B formed therein for detachably attaching the module 10 to the housing 30. These module mounting holes 16B may have screw threads or may be simple through holes. In the example in Figure 6, four module mounting holes 16B are formed. Furthermore, the module board 16 also has plate mounting holes 16C formed therein for attaching the heat sink 14. Here, the plate mounting holes 16C can be used interchangeably with the module mounting holes 16B. In the example in Figure 6, the upper left module mounting hole 16B' is used interchangeably with the plate mounting hole 16C. Note that in Figure 6, some of the mounting holes are covered by screws.

[0038] The housing 30 of the driver unit 100 is configured to allow the control board 21 to be attached and detached. Specifically, as shown in Figure 7, the driver unit 100 includes a housing board 41 to which the control board 21 is attached and detached. The housing board 41 has a second housing terminal 41B that is connected to the control board terminal 22A for input and output of the control board 21, as shown in Figure 9. The housing board 41 has both ends extending in the longitudinal direction that are inserted into slits formed inside the central part 34 of the housing. As a result, the housing board 41 is held in place by the driver unit 100 via the central part 34 of the housing. Consequently, the control board 21 becomes detachable from the housing 30 via the housing board 41. In this way, the housing 30 is configured to allow the control board 21 to be attached and detached. Alternatively, the housing 30 may be configured so that the control board 21 is snap-fitted into place.

[0039] Furthermore, the housing substrate 41 is provided with screw posts 42 at positions corresponding to the module mounting holes 16B. The module 10 is then detachably attached to the central part 34 of the housing 30 via the housing substrate 41. That is, the module 10 is detachably attached to the housing substrate 41 by screws inserted into the screw posts 42 fixed to the housing substrate 41. The housing substrate 41 also has a housing first terminal 41A that is connected to the module terminal 16A. This housing first terminal 41A is a female terminal, but it may also be a male terminal.

[0040] In Figure 7, there are four screw posts 42 corresponding to each module 10. And, corresponding to the number of screw posts 42, four module mounting holes 16B are formed in the module 10. However, there may be one screw post 42, or there may be three or fewer, or five or more. In this case, the module 10 will have a number of module mounting holes 16B corresponding to the number of screw posts 42.

[0041] As shown in Figure 8, the height of the screw post 42 is set to match the height from the housing substrate 41 to the bottom surface of the module substrate 16 when the module terminal 16A is connected to the housing first terminal 41A. In other words, the height of the screw post 42 is set so that when the module terminal 16A is connected to the housing first terminal 41A, the bottom surface of the module substrate 16 contacts the top surface of the screw post 42. This allows the module substrate 16 to be supported by the screw post 42 when the module terminal 16A is connected to the housing first terminal 41A. Alternatively, a separate support part may be provided to support the module 10.

[0042] Module 10 is attached to housing 30 by connecting module terminal 16A to housing terminal 41A and inserting screws into module mounting hole 16B and screw post 42. Module 10 can also be removed from housing 30 by removing the screws from module mounting hole 16B and screw post 42. In this way, module 10 is detachably attached to housing 30.

[0043] [Control board] The control board 21 will be described with reference to Figures 9 and 10. Figure 9 shows the control board 21 viewed from the front and above. Figure 10 shows the driver unit 100 viewed from above.

[0044] As shown in Figure 9, the control board 21 comprises a main board 22 and a processor 23. The control board 21 also has control board terminals 22A and screw posts 22B fixed to the main board 22. Furthermore, the control board 21 has an edge portion 22C on which the control board terminals 22A are located. The screw posts 22B are provided at both ends of the edge portion 22C. Note that although the control board terminals 22A in Figure 9 are male terminals, they may also be female terminals.

[0045] Furthermore, as shown in Figure 7, the housing substrate 41 has a second housing terminal 41B that is connected to the control board terminal 22A. This second housing terminal 41B is a female terminal, but it may also be a male terminal. The housing 30 is configured so that the control board 21 can be attached to it. That is, the control board 21 is detachably attached to the housing substrate 41. The housing substrate 41 is then held by the driver unit 100 via the central housing portion 34.

[0046] Returning to Figure 9, a screw post 22B is fixed to the control board 21. The control board 21 is then detachably attached to the housing board 41 by screws inserted into the screw post 22B from the back of the central part 34 of the housing. In this way, the housing 30 is configured so that the control board 21 can be detachably attached via the housing board 41. This allows the control board 21 to be easily replaced. Alternatively, the control board 21 may be attached to the housing 30 by other methods such as screw fastening.

[0047] Furthermore, since the control board 21 can be easily replaced, the user can install a control board 21 of their own design into the driver unit 100. For example, if it becomes difficult to obtain the processor 23 and it becomes necessary to use a different type of processor 23 than the existing one, or if the user wants to increase the memory capacity, the user can design a new control board 21. Then, after replacing the existing control board 21 with the newly designed control board 21, the user can continue to use the module 10 as is. This reduces the cost and man-hours required for designing the driver unit 100.

[0048] Furthermore, the edge portion 22C is located at the lower end of the main board 22 and extends in the longitudinal direction. The height of the screw post 22B is set so that when the control board terminal 22A is connected to the second housing terminal 41B, the lower surface of the screw post 22B contacts the upper surface of the housing board 41. The control board 21 is mounted on the housing board 41 in an upright position. Therefore, when the control board terminal 22A is connected to the second housing terminal 41B, the screw post 22B supports the control board 21. This allows for effective use of the space inside the housing 30. Even if no screws are inserted into the screw post 22B, the control board 21 can be maintained in an upright position.

[0049] As shown in Figure 10, the driver unit 100 comprises multiple modules 10. The control board 21 is positioned between the multiple modules 10. This creates an airflow path for air discharged from the cooling fan 11 between the main board 22 of the control board 21 and the heat sink 14 of the module 10. For example, the housing 30 is fitted with two modules 10, a right module 10R and a left module 10L, both with the same structure. The control board 21 is positioned between the right module 10R and the left module 10L. This creates an airflow AL of air discharged from the left cooling fan 11L between the main board 22 and the left heat sink 14L of the left module 10L. Therefore, the left module 10L can be cooled efficiently.

[0050] The right module 10R has a right heat sink 14R with a roughly L-shaped horizontal cross-section, and the left module 10L has a left heat sink 14L with a roughly L-shaped horizontal cross-section. The right heat sink 14R and the left heat sink 14L have a base facing the fins 11F that extends in the left-right direction in Figure 10, and the bent ends extending from the base extend in the longitudinal direction of the housing 30. As a result, the left heat sink 14L is closer to one side wall of the central part 34 of the housing than the right heat sink 14R.

[0051] Furthermore, the right drive signal generation unit 13R of the right module 10R is located between the right heat sink 14R and the other side wall of the central part 34 of the housing. In the right heat sink 14R, the direction in which the bent end extends from the base is aligned with the direction in which the air discharged from the left cooling fan 11L flows. Similarly, in the left heat sink 14L, the direction in which the bent end extends from the base is aligned with the direction in which the air discharged from the right cooling fan 11R flows.

[0052] Furthermore, the control board 21 mounted on the housing 30 is closer to the left module 10L than to the right module 10R in Figure 10. In other words, the mounting position of the control board 21 is closer to the left module 10L than to the right module 10R. The left drive signal generation unit 13L of the left module 10L is located between the main board 22 of the control board 21 and the left heat sink 14L of the left module 10L. As a result, an airflow path (i.e., airflow AL) for air discharged from the left cooling fan 11L is formed between the main board 22 and the left heat sink 14L. Therefore, the left module 10L can be cooled efficiently.

[0053] Furthermore, the right module 10R is mounted such that its right heat sink 14R faces the inner surface of the side wall of the central part 34 of the housing. The right drive signal generation unit 13R of the right module 10R is located between the right heat sink 14R of the right module 10R and the side wall of the central part 34 of the housing. As a result, an airflow path (i.e., airflow AR) is formed between the right heat sink 14R and the side wall of the central part 34 of the housing, through which air is discharged from the right cooling fan 11R. Therefore, the right module 10R can be cooled efficiently.

[0054] Furthermore, the right cooling fan 11R and the left cooling fan 11L also dissipate heat from the driver unit 100. For this purpose, as shown in Figure 2, an air vent 31A is formed in the front part 31 of the housing through which air passes. As a result, air flowing in through the air vent 31A passes through the housing 30 and is discharged to the outside of the housing 30 by the right cooling fan 11R and the left cooling fan 11L. Consequently, the internal space of the housing 30 is cooled.

[0055] With the driver unit 100 described above, a user can create a driver unit 100 that achieves the desired specifications simply by designing the control board 21. In other words, a driver unit 100 that achieves the desired specifications can be provided to the user simply by designing the control board 21. Furthermore, since the module 10 and the control board 21 are detachably mounted, component replacement is easy. In addition, since the control board 21 is mounted in an upright position, it can be replaced even more easily.

[0056] Furthermore, module 10 can be removed from the housing 30 by removing the screws from the module mounting holes 16B and screw posts 42. In this way, module 10 can be easily replaced. Therefore, for example, when a transformer that amplifies the electrical signal S2 more significantly is used as the drive signal generation unit 13, module 10 can be replaced with one having a different drive signal generation unit 13. After replacing module 10, the user can continue to use the control board 21 as is. This reduces the cost and man-hours required for the design of the driver unit 100.

[0057] [Differentiation] In the embodiment shown in Figure 10, the driver unit 100 comprises two modules 10 having the same structure. However, the driver unit 100 may also comprise two modules 10 having different shapes. As an example, Figure 11 shows two right heat sinks 214R and a left heat sink 214L according to a first modification, and two right heat sinks 314R and a left heat sink 314L according to a second modification.

[0058] As shown in Figure 11A, the right heat sink 214R and the left heat sink 214L in the first modified example both extend to a position close to the side wall of the central part 34 of the housing at their respective ends. The right heat sink 214R and the left heat sink 214L have shapes that are symmetrical with respect to the control board 21 located midway between them. As a result, an airflow path (i.e., airflow AL) is formed between the control board 21 and the left heat sink 214L for air discharged from the left cooling fan 11L. Also, an airflow path (i.e., airflow AR) is formed between the control board 21 and the right heat sink 214R for air discharged from the right cooling fan 11R. Therefore, the two modules 10 can be cooled efficiently. Furthermore, since the airflow inside the housing 30 is not obstructed, the cooling effect can be enhanced.

[0059] Furthermore, as shown in Figure 11B, the right heat sink 314R and the left heat sink 314L in the second modified example both extend to a position close to the control board 21. The right heat sink 314R and the left heat sink 314L have shapes that are symmetrical with respect to the control board 21, which is located midway between them. As a result, an airflow path (i.e., airflow AL) for air discharged from the left cooling fan 11L is formed between the side wall of the housing 30 and the left heat sink 214L. In addition, an airflow path (i.e., airflow AR) for air discharged from the right cooling fan 11R is also formed between the side wall of the housing 30 and the right heat sink 214R. Therefore, the two modules 10 can be cooled efficiently. Moreover, the right heat sink 314R and the left heat sink 314L are positioned closer to the center of the housing 30. Therefore, the cooling effect can be further enhanced compared to the case where the right heat sink 314R and the left heat sink 314L are closer to the side wall of the housing 30.

[0060] Although the present invention has been described above with reference to the embodiments, the present invention is not limited to the embodiments described above. Inventions modified within the scope that does not contradict the present invention, and inventions equivalent to the present invention are also included in the present invention. Furthermore, each embodiment and each variation, as well as the technical means included in each embodiment or each variation, can be appropriately combined within the scope that does not contradict the present invention.

[0061] For example, an additional temperature sensor may be provided between the two drive signal generation units 13. This allows for accurate detection of temperature rise caused by heat generation in the drive signal generation units 13. In the above embodiment, the heat sink 14 and cooling fan 11 are provided on the module 10. However, the heat sink 14 and cooling fan 11 may be provided on the housing 30 instead of the module 10. However, providing the heat sink 14 and cooling fan 11 on the module 10 allows for more efficient heat dissipation in each module 10. Also, the temperature sensor 17 may be provided on the housing 30 instead of the module 10. However, providing the temperature sensor 17 on the module 10 allows for more accurate temperature control of each module 10.

[0062] Furthermore, the control board 21 may be arranged alongside the modules 10, rather than between them. For example, the control board 21 may be placed between the modules 10 and the side wall of the central part 34 of the housing. However, the cooling effect can be further enhanced by placing the control board 21 between the modules 10. Also, the direction in which the multiple drive signal generation units 13 are arranged and the direction in which the multiple signal amplification units 12 are arranged may be different. For example, the direction in which the multiple drive signal generation units 13 are arranged and the direction in which the multiple signal amplification units 12 are arranged may intersect. Moreover, the driver unit 100 does not necessarily have a control board 21. In this case, the driver unit 100 receives a control signal S1 from an external device (e.g., a control circuit) which will be the basis for the drive signal S3. The driver unit 100 then generates the drive signal S3 based on the control signal S1 and drives the piezoelectric motor 90.

[0063] Some or all of the above embodiments may also be described as follows, but are not limited to the following:

[0064] (Note 1) A driver unit that generates a drive signal for a piezoelectric motor based on a control signal generated by a control board, The housing is configured to allow the control board to be attached and detached, The housing is equipped with a detachable signal generation module, The signal generation module is a driver unit comprising: an amplification unit that amplifies the control signal to generate an electrical signal; a signal generation unit that generates the drive signal from the electrical signal; and a module board on which the amplification unit and the signal generation unit are fixed.

[0065] (Note 2) The signal generation module is the driver unit described in Appendix 1, which includes a heat sink and a cooling fan.

[0066] (Note 3) The signal generation module has a plurality of amplification units and a temperature sensor. The temperature sensor is a driver unit as described in Appendix 1 or 2, which is positioned between a plurality of amplification units.

[0067] (Note 4) The signal generation module has a plurality of signal generation units and a plurality of amplification units, The driver unit according to any one of the appendices 1 to 3, wherein the direction in which the multiple signal generation units are arranged and the direction in which the multiple amplification units are arranged are the same.

[0068] (Note 5) The control board is provided, The driver unit according to any one of the appendices 1 to 4, wherein the control board has an edge portion on which control board terminals are provided and screw posts provided at both ends of the edge portion.

[0069] (Note 6) The system comprises multiple signal generation modules, The control board is the driver unit described in Appendix 5, which is located between a plurality of signal generation modules.

[0070] (Note 7) A signal generation module that generates a drive signal for a piezoelectric motor based on a control signal generated by a control board, A signal generation module comprising: an amplification unit that amplifies the control signal to generate an electrical signal; a signal generation unit that generates the drive signal from the electrical signal; and a module board on which the amplification unit and the signal generation unit are fixed. [Explanation of Symbols]

[0071] 10: Module (Signal Generation Module) 11: Cooling fan 12: Amplification section (signal amplification section) 13: Signal generation unit (drive signal generation unit) 14: Heat sink 16: Module board 17: Temperature sensor 21: Control board 22A: Control board terminal 22B: Screw Post 22C:Edge 30: Cabinet 90: Piezoelectric motor 100: Driver Unit S1: Control signal S2: Electrical signal S3: Drive signal

Claims

1. A driver unit that generates a drive signal for a piezoelectric motor based on a control signal generated by a control board, The housing is configured to allow the control board to be attached and detached, The housing is equipped with a detachable signal generation module, The signal generation module is a driver unit comprising: an amplification unit that amplifies the control signal to generate an electrical signal; a signal generation unit that generates the drive signal from the electrical signal; and a module board on which the amplification unit and the signal generation unit are fixed.

2. The driver unit according to claim 1, wherein the signal generation module comprises a heat sink and a cooling fan.

3. The signal generation module has a plurality of amplification units and a temperature sensor. The driver unit according to claim 1 or 2, wherein the temperature sensor is arranged between a plurality of amplification units.

4. The signal generation module has a plurality of signal generation units and a plurality of amplification units, The driver unit according to claim 1 or 2, wherein the direction in which the plurality of signal generation units are arranged and the direction in which the plurality of amplification units are arranged are the same.

5. The control board is provided, The driver unit according to claim 1 or 2, wherein the control board has an edge portion on which control board terminals are provided, and screw posts provided at both ends of the edge portion.

6. The system comprises multiple signal generation modules, The driver unit according to claim 5, wherein the control board is located between a plurality of signal generation modules.

7. A signal generation module that generates a drive signal for a piezoelectric motor based on a control signal generated by a control board, A signal generation module comprising: an amplification unit that amplifies the control signal to generate an electrical signal; a signal generation unit that generates the drive signal from the electrical signal; and a module board on which the amplification unit and the signal generation unit are fixed.

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