Ultrasonic measuring device for industrial measuring devices
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- RENISHAW PLC
- Filing Date
- 2023-06-22
- Publication Date
- 2026-06-30
Smart Images
Figure 00000000_0000_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to an ultrasonic measuring device for industrial measuring devices such as machine tools, and more particularly to such an ultrasonic measuring device having a base to which an elongated stem including an ultrasonic transducer can be attached.
Background Art
[0002] It is known to use ultrasonic devices to measure industrially manufactured parts such as turbine blades, engine components, etc. Such ultrasonic measurements can be used, for example, to measure the thickness of such parts or to identify defects within those parts. Ultrasonic devices are generally handheld, allowing manual ultrasonic inspection by trained operators, but automated industrial ultrasonic inspection systems are also known. For example, it is known that ultrasonic measuring devices can be attached to industrial measuring devices such as computer numerical control (CNC) machine tools or coordinate measuring machines (CMMs). Such devices allow automatic inspection of parts before, during, or after a machining process.
[0003] Patent Document 1 describes an ultrasonic measuring device attached to a CMM by a two-axis rotary head that enables fine adjustment of the angle of an ultrasonic probe relative to the surface of an object. The ultrasonic device of Patent Document 1 is modular and includes a base portion that houses a transducer, and a passive coupling module that may include self-lubricating hydrophilic elastomer balls contained in a shell can be attached and removed in an automated manner.
[0004] An ultrasonic device that can be attached to a spindle of a machine tool to enable ultrasonic measurement during machining is described in Patent Document 2. The corresponding ultrasonic measurement device is sold under the product name RWP20.50 - G - UTP by the Hexagon AB group in Stockholm, Sweden. In a first embodiment described with reference to FIGS. 1 and 2 of Patent Document 2, a measuring instrument (labeled with reference numerals 9 and 22 in FIGS. 1 and 2 of Patent Document 2 respectively) that can be attached to a tool holder of a machine tool is described. The measuring instrument is linked to a transceiver unit 11 outside the machine tool housing by a wireless (wireless or optical) signal line 18. The ultrasonic measurement unit (label 23) is attached to the measuring instrument by a screw connection, and an electrical link is provided between the measuring instrument and the ultrasonic measurement unit.
[0005] The inventors recognize that the configuration described in Patent Document 2 has various drawbacks. For example, the provision of two housing parts (i.e., separate housing parts forming the measuring instrument and the ultrasonic measurement unit respectively) makes the overall arrangement quite bulky, thereby hindering or preventing the rapid measurement of smaller objects or objects having a surface with restricted access (such as a bore), and when different ultrasonic configurations are required, it is necessary to replace the entire ultrasonic measurement unit.
[0006] Patent Document 3 describes a handheld ultrasonic monitoring system in which an ultrasonic sensor can be mechanically and electrically connected to a housing via a multi - pin connector. Patent Document 4 describes a thickness gauge in which a sensor head is removable from a mobile handheld unit. Patent Document 5 describes a handheld non - destructive testing system having a connector for attaching a probe head to a flexible shaft. The connector of Patent Document 5 includes a LEMO (registered trademark) connector that enables the establishment of a plurality of electrical connections. A medical imaging device (i.e., not an industrial measurement device) is described in Patent Document 6 where the connector provides mechanical, electrical and optical connections.
Prior Art Documents
Patent Documents
[0007]
Patent Document 1
Patent Document 2
Patent Document 3
Patent Document 4
Patent Document 5
Patent Document 6
Summary of the Invention
[0008] According to a first aspect of the present invention, there is provided an ultrasonic measuring device for an industrial measuring device, a base including an ultrasonic transducer driver, an elongated stem including an ultrasonic transducer, a connector assembly for releasably attaching the elongated stem to the base, the connector assembly including a first connector portion provided on the base and a second connector portion provided at a proximal end of the elongated stem, wherein when the first and second connector portions are connected, they provide mechanical alignment of the elongated stem with respect to the base and provide an electrical connection between the ultrasonic transducer and the ultrasonic transducer driver, and a connector assembly; The ultrasonic measuring device is characterized in that the connector assembly includes a coaxial electrical connector that enables the electrical connection between the ultrasonic transducer and the ultrasonic transducer driver to be established with the elongated stem fixed to the base in any rotational direction about the longitudinal axis of the elongated stem.
[0009] Accordingly, there is provided an ultrasonic measuring device configured to be used together with an industrial measuring device. Such an industrial measuring device may include a dedicated measuring machine (e.g., a coordinate measuring machine or a robot) or a machine tool (e.g., a cutting or grinding machine) that processes (e.g., cuts or grinds) the portion to be measured. It should be noted that industrial measurement refers to the measurement of industrially manufactured objects. For example, industrial measurement may include the measurement of the thickness of manufactured parts (e.g., metal parts) or the detection of defects in such manufactured parts. To avoid misunderstanding, the industrial measuring device excludes medical ultrasonic devices (such as those described in Patent Document 6) used for measuring or imaging the human or animal body.
[0010] The ultrasonic measuring device includes a base from which an elongated stem extends. The base is also attachable to the industrial measuring device. For example, the base may include a tool shank or the like that enables the base to be removably attached to a tool holder provided on a spindle of a machine tool. The elongated stem includes an ultrasonic transducer that can be used to transmit and / or receive ultrasonic waves. For example, the ultrasonic transducer may enable the detection of defects or the measurement of thickness of industrially manufactured parts. An ultrasonic transducer driver provided on the base includes electronic equipment that drives the ultrasonic transducer during use (e.g., transmits and / or receives ultrasonic waves).
[0011] The elongated stem is removably attachable to the base via a connector assembly. Thus, during use, the elongated stem is attached to the base by the connector assembly. The connector assembly is formed from two mutually engagable parts or connector portions. The first connector portion is provided on the base, and the second connector portion is provided at the proximal end of the elongated stem. In other words, the base includes the first connector portion and the elongated stem includes the second connector portion. The connector assembly is arranged such that when the first and second connector portions are connected to each other, the elongated stem is mechanically aligned with respect to the base. For example, the longitudinal axis of the elongated stem may be aligned with the central axis of the base portion. Further, the connector assembly also provides an electrical connection between the base and the elongated stem that enables an electrical connection to be provided between an ultrasonic transducer and an ultrasonic transducer driver. Thus, the electrical connection electrically connects the transducer to the transducer driver, thereby enabling the transducer driver to pass a signal to the ultrasonic transducer and / or receive a signal from the ultrasonic transducer. In other words, the connector assembly provides both a mechanical linkage and an electrical connection between the base and the elongated stem.
[0012] The connector assembly includes a coaxial electrical connector that provides the necessary electrical link between the ultrasonic transducer and the ultrasonic transducer driver. With this configuration, the elongated stem can be fixed to the base in any rotational direction about the longitudinal axis of the elongated stem. In other words, the rotational direction of the elongated stem relative to the base is not restricted or limited by the need to ensure that complementary electrical contacts (e.g., pins / apertures) are rotationally aligned with each other. The ability to connect the coaxial electrical connector in any rotational direction means that the rotational direction of the elongated stem relative to the base that can be employed is not restricted. Importantly, this enables the elongated stem to be attached to the base in the required rotational direction when the elongated stem is attached to an industrial measuring device. Since there is no need to carefully align the rotational direction of the elongated stem relative to the base, this makes it easier for the operator to attach the elongated stem to the base, particularly when the base is attached to a machine tool and is in a position that restricts the visibility or access to the connector. Also, the rotational direction of the elongated stem can be appropriately selected. As will be described in more detail below, in some embodiments, the elongated stem can be asymmetric (e.g., bent or dogleg, etc.), and the ability to select the angular direction of the elongated stem for such an arrangement can enable the automatic collection of measurements from surfaces having different directions.
[0013] The handheld devices of Patent Document 3, Patent Document 4, Patent Document 5, and Patent Document 6 do not include such coaxial electrical connectors (i.e., the connectors of such prior art devices need to employ a unique rotational alignment to enable mutual engagement), and such coaxial connectors are not necessary for the operator to align such devices with the object being inspected (i.e., because the rotational direction can be adjusted by hand). Further, unlike the configuration described in Patent Document 1 where the (passive) coupling module is replaceable, the device of the present invention enables the removal and reattachment of an elongated stem including an ultrasonic transducer. Thus, the present invention enables the quick and easy replacement of the elongated stem. For example, the elongated stem can be replaced with an elongated stem of a different length, an elongated stem having a different transducer type, an elongated stem having a different coupling element for acoustically coupling to the surface of the object being inspected, or an elongated stem having a different holder for holding such a coupling element. The stem extension member can also be disposed between the base and the elongated stem, as will be described in more detail below.
[0014] The arrangement of the present invention also provides various advantages over the ultrasonic device described in Patent Document 2. For example, the removable attachment of the elongated stem via the connector assembly enables the quick and easy attachment of various elongated stems to the base portion. Importantly, such elongated stems include transducers, and the same transducer driver of the base can be used with each such elongated stem. This can reduce the cost of reconfiguring measurement devices used for different types of measurements (e.g., providing stems of different lengths or different types of ultrasonic transducers), and can also provide a more compact arrangement.
[0015] Advantageously, the first connector portion includes a first reference plane, and the second connector portion includes a second reference plane. The engagement of these first and second reference planes provides an alignment of the elongated stem with respect to the base when the first and second connector portions are connected. In other words, the mechanical alignment of the elongated stem and the base is defined by the interaction of the first and second reference planes. The first and / or second reference plane(s) can be flat surfaces that, when engaged, provide alignment of the elongated stem with respect to the base. The first and second reference planes can be substantially rigid. In this way, the elongated stem can be attached to the base in a known repeatable orientation.
[0016] It should also be noted that the base can include a movable joint. The first connector portion can then be attached to the remainder of the base via the movable joint. For example, the base can include a housing and a movable joint to which the first connector portion is attached to the housing. The movable joint can allow the first connector portion, and thus any attached elongated stem, to move (e.g., tilt or slide) with respect to the housing. If such a movable joint is provided, it can define a rest position in the absence of an applied external force. The elongated stem can then be movable away from the (pre-defined) rest position to enable it to align with the surface of the object being measured.
[0017] The elongated stem can have any suitable shape. The elongated stem can include an elongated tubular member, for example, it can be provided in the form of a tube or a tubular sleeve. The elongated stem can be substantially straight. The elongated stem can be rigid. The elongated stem can be substantially non-flexible. The elongated stem may not be straight. For example, the elongated stem can include an angled joint, a twist, a curved portion, or a dog-leg connection. The ability to control the rotational orientation of a non-straight stem has the advantage of enabling alignment of the distal end of the stem with the surface being measured. At least a portion of the elongated stem can be hollow or can include a hollow internal cavity. The elongated stem can have any suitable cross-sectional shape, such as a square, rectangular, or elliptical cross-section. Advantageously, the elongated stem has a substantially circular cross-section. The length of the elongated stem can be at least 5 times its radius. The length of the elongated stem can be at least 10 times its radius. The radius of the elongated stem can be smaller than the radius of the base. Preferably, the radius of the elongated stem is less than or equal to half of the radius of the base. The elongated stem can include a single piece or tube (i.e., can be provided as a single component). Alternatively, the elongated stem can be formed from a plurality of sections (e.g., a plurality of tubular sections). These sections can be permanently attached to each other (e.g., joined). Alternatively, such sections can be removably attached to each other to allow for removal or replacement of sections as needed. The ability to disassemble an elongated tubular stem can be advantageous for maintenance or repair purposes.
[0018] An ultrasonic coupling element for acoustically coupling to an object may also be provided at the distal end of the elongated stem. An ultrasonic transducer assembly may then be provided that includes the ultrasonic transducer and the ultrasonic coupling element. For example, the ultrasonic transducer may be arranged to physically and acoustically contact the transducer contact (rear) surface of the ultrasonic coupling element. Such physical contact may be direct or indirect (e.g., via an intermediate component such as an adhesive). The ultrasonic waves generated by the ultrasonic transducer can then be coupled to the object to be inspected via the ultrasonic coupling element. The ultrasonic coupling element may be formed from any suitable ultrasonic transmission material. For example, the ultrasonic coupling element may include a hard (rigid) ultrasonic material (e.g., Lexolite) that enables the ultrasonic coupling element to provide a datum surface. Preferably, the ultrasonic coupling element includes a so-called dry or soft coupling material (e.g., a thermosetting silicone rubber) that enables ultrasonic coupling to the object without the need for use of an ultrasonic coupling gel. In other words, the ultrasonic coupling element may include an elastic (i.e., elastically deformable) ultrasonic coupling element.
[0019] The distal end of the elongated stem preferably includes a datum surface for ultrasonic measurement. When a coupling element including a hard ultrasonic material is provided, the datum surface may be provided by the surface of the coupling element. Alternatively, for example, when the coupling element includes a dry (soft) coupling material, the rigid surface of the elongated stem may provide the reference surface. For example, the distal end of an outer tubular sleeve may provide a datum surface. The transducer may also be properly aligned with respect to the datum surface. For example, the transducer may be movably mounted within the elongated stem such that it can translate back and forth along the longitudinal axis of the elongated stem.
[0020] The datum surface provides a physical reference or datum configured to contact the object to be measured. The datum surface is conveniently pre - aligned with the second reference surface of the second connector portion. For example, the second reference surface can be aligned with the datum surface within 0.5°, more preferably within 0.25°, and even more preferably within 0.1°. In this way, the datum surface can also be aligned with the first reference surface of the first reference portion. For example, the connector assembly can ensure that (when the first and second connector portions are connected) the datum surface is aligned parallel to the first reference surface within 0.5°, more preferably within 0.25°, and even more preferably within 0.1°. The datum surface can include an annular surface or ring. When a movable joint is provided as described above, the datum surface can provide a reference surface that allows the elongated stem to mechanically self - align with the surface of the object being inspected. For example, the plane of the datum surface can be configured to lie parallel to the plane of the surface it contacts, thereby allowing ultrasonic waves to be coupled to the object along a specific direction (e.g., along the surface normal of the object). The datum surface can include a single continuous datum surface (e.g., an annular ring or a flat plate), or can be formed from a plurality of (non - continuous) spaced - apart surface sections (e.g., a plurality of partial ring segments). In a preferred embodiment, the elongated stem can include a tubular sleeve, and the distal end of the elongated (tubular) stem can provide the datum surface. For example, if the elongated member is tubular and has a circular cross - section, the distal annular end face of the elongated tubular member can provide a planar datum surface.
[0021] The elongated stem can be mechanically locked to the base. In other words, a locking mechanism for releasably locking the elongated stem to the base can be provided. The locking mechanism can prevent rotation of the elongated stem relative to the base when locked. The connector assembly can include the locking mechanism. In this way, the locking mechanism can releasably lock the first and second connector portions together. Advantageously, the connector assembly comprises an operable locking mechanism for releasably locking the engagement of the first and second reference planes. Thus, the locking mechanism can ensure that the first and second reference planes remain engaged or locked when the locking mechanism is actuated. The locking mechanism can also be unlocked to allow the first and second reference planes to disengage.
[0022] The locking mechanism can be implemented in a variety of different ways. In a preferred embodiment, the operable locking mechanism comprises an internally threaded collar for engaging at least one externally threaded portion of the first and / or second connector portion. The collar can be rotatably attached to one of the first and second connector portions using an external thread provided on the other of the first and second connector portions that engages the internal thread of the collar. Rotation of the collar in a first direction can firmly engage the first and second reference planes through interaction with the external threaded portion. Rotation in the opposite direction can then be used to release the engagement of the first and second reference planes, thereby unlocking the connector assembly. In this way, a robust physical connection can be established that maintains a fixed relative position of the first and second reference planes. The axis of rotation of the collar can be coaxial with the axis of the coaxial connector.
[0023] As described above, the connector assembly includes a coaxial electrical connector that provides an electrical connection between the ultrasonic transducer and the ultrasonic transducer driver while allowing the elongated stem to be fixed to the base in any rotational direction about the longitudinal axis of the elongated stem. In other words, the elongated stem can be attached to the base in any rotational direction. The coaxial electrical connector can be axially symmetric. Conveniently, the entire connector assembly is axially symmetric. Thus, the connector assembly allows the elongated stem to be attached in different axial directions. Next, the lock mechanism described above can lock the elongated stem in such an orientation during use. This is advantageous because it allows the user to set the rotational direction of the elongated stem before the elongated stem is locked in place. This enables, for example, the use of an elongated stem with an angled transducer and coupling element away from the longitudinal axis of the elongated stem to measure a surface inclined with respect to the base without adjusting the orientation of the base. In other words, the elongated stem can be aligned to allow engagement of its coupling element with the surface being measured.
[0024] As described above, the connector assembly also provides an electrical link between the ultrasonic transducer driver within the base and the ultrasonic transducer within the elongated stem. This electrical link is provided by the coaxial electrical connector. Advantageously, the connector assembly includes an electrical connector (i.e., the coaxial electrical connector) that includes a first portion and a second portion. Preferably, the first connector portion includes the first portion of the electrical connector and the second connector portion includes the second portion of the electrical connector. Thus, the physical connection of the first and second connector portions also acts to engage the first and second portions of the electrical connector with each other to provide an electrical connection between the transducer driver and the transducer.
[0025] In a preferred embodiment, the first part of the electrical connector is movable laterally with respect to the base. If the first connector part of the base includes the first reference plane as described above, the first part of the electrical connector is preferably movable laterally with respect to the first reference plane. The second part of the electrical connector may also or alternatively be movable laterally with respect to the elongate stem. If the second connector part includes the second reference plane as described above, the second part of the electrical connector is preferably movable laterally with respect to the second reference plane. In this context, the lateral (left - right) movement of the part of the electrical connector means having a component of movement permitted in a direction orthogonal to the longitudinal axis of the elongate stem.
[0026] The allowable range of lateral movement means that the forces involved in establishing the physical connection between the first and second connector parts can be somewhat separated from the forces applied to the first and second parts of the electrical connector. In other words, enabling the lateral movement of the first and second parts of the electrical connector allows those parts to provide an electrical connection without their relative positions being restricted by the physical connection between the first and second connector parts. This can reduce wear, prevent damage to the first and second parts of the electrical connector, and thereby improve the reliability and lifespan of the electrical link (i.e., maintain good electrical contact even in the presence of vibrations). Advantageously, the electrical connector can also withstand changes in the axial (longitudinal) position of the first and second parts of the electrical connector. This also makes it possible to establish and maintain a good electrical link while preventing damage to the electrical connector and ensuring that the electrical connector does not interfere with the physical connection between the first and second connector parts.
[0027] The first connector portion and the second connector portion can be configured to angularly constrain the elongate stem with respect to the base without tightly constraining their relative lateral positions (e.g., ensuring that the elongate stem projects from the base along a defined direction). For example, if first and second reference planes are provided as part of the first and second connector portions, they can include flat surfaces that define the relative angular alignment of the elongate stem with respect to the base while allowing some lateral play in the physical connection. The electrical connector can then define the relative lateral positions of the first and second connector portions, and the first and second reference planes define the angular alignment. When connected, the first and second connector portions preferably lock firmly the relative positions of the elongate stem and the base. This prevents further relative movement of the first and second portions of the electrical connector after the elongate stem has been attached (e.g., locked) to the base.
[0028] The ultrasonic transducer can operate as an ultrasonic transmitter. The ultrasonic transducer can operate as an ultrasonic receiver. The ultrasonic transducer can operate as both an ultrasonic transmitter and receiver (i.e., can be an ultrasonic transceiver). The ultrasonic transducer driver can be arranged to send an electrical signal to the ultrasonic transducer to cause the transducer to emit ultrasonic waves. The ultrasonic transducer driver can be arranged to receive an electrical signal from the ultrasonic transducer generated by the received ultrasonic waves. The ultrasonic transducer driver can be configured to send an electrical signal to the ultrasonic transducer and receive an electrical signal from the ultrasonic transducer.
[0029] As described above, the electrical connector of the device comprises a coaxial electrical connector. In other words, the coaxial electrical connector comprises two or more concentric conductors separated by an electrical insulator. For example, an insulated central signal line can be surrounded by an outer concentric shield. This type of coaxial connector is advantageous, i.e., it allows relatively high voltage and frequency transmission signals to be applied to the ultrasonic transducer without generating unwanted electromagnetic noise (e.g., to ensure compliance with EMC requirements), and allows low-intensity received signals to be returned to the ultrasonic transducer driver (i.e., having an acceptably high signal-to-noise ratio). The axis of the coaxial electrical connector can also coincide with the longitudinal axis of the elongated stem. The axis of the coaxial electrical connector can also coincide with the relative rotation axis of the first and second connector parts.
[0030] The first and second parts of the coaxial electrical connector can be engaged by a push-fit action. When the first and second parts of the electrical connector are engaged, there may be no significant rotation between them. For example, it may not be necessary to rotate the first and second parts relative to each other (e.g., the relative rotation of the first and second parts may be less than half a turn). Thus, the electrical connection is provided by a push-fit (longitudinal or axial) movement of the first and second parts of the electrical connector. This push-fit action reduces physical wear and damage that may result from relative rotation of the first and second parts of the connector (e.g., a coaxial connector of the type described above) while the first and second parts are engaged with each other.
[0031] In a preferred embodiment, following the engagement of the first and second portions of the electrical connector using a push-fit action, the locking mechanism is actuated to mechanically lock the first and second connector portions together (e.g., engage with the first and second reference surfaces and lock in a predetermined position). The mechanical lock can be provided, as described above, by rotating the collar of the locking mechanism to fix or lock the first and second connector portions together. Allowing lateral movement of the first and second portions of the electrical connector reduces any lateral forces on the first and second portions of the electrical connector resulting from the actuation of the locking mechanism, thereby reducing the risk of damage to the electrical connector and ensuring that the electrical connection is as noise-free as possible.
[0032] The ultrasonic measuring device is configured for use in an industrial environment. Thus, the ultrasonic measuring device may be machine-mounted or machine-mountable rather than being handheld or carried manually. The ultrasonic measuring device may be attachable to a machine tool. For example, the ultrasonic measuring device may be attached or attachable to a shank that can be held on the spindle of a machine tool. Thus, the device can be used within the housing of a machine tool where there may be a high-pressure jet of coolant and chips are often ejected at high speed during cutting. Thus, the connector assembly preferably comprises one or more seals for preventing the ingress of fluid when the first and second connector portions are connected to each other. For example, the first and second portions of the connector assembly may include one or more O-ring seals to provide a fluid-tight seal. The fluid-tight seal can prevent fluid from reaching the coaxial electrical connector. The first and second connector portions may also be arranged to prevent the ingress of fluid into the stem and / or base when they are not connected to each other.
[0033] Advantageously, the base comprises one or more batteries. In other words, the base of the attached elongated stem and the transducer are driven by an internal battery. The base also conveniently comprises a wireless communication unit for wirelessly transmitting measurement data obtained from the ultrasonic transducer to a remote interface. The wireless communication unit may transmit and / or receive measurement data via an optical link. The wireless communication unit may transmit and / or receive measurement data via a wireless link (such as a spread spectrum link, such as a frequency hopping spread spectrum link). The use of an internal battery and a wireless communication link eliminates the need for subsequent wires and enables the device to be stored in a tool change carousel adjacent to the machine tool housing and automatically exchanged with cutting tools etc. as required. An interface unit may also be provided to communicate with the wireless communication unit of the ultrasonic measuring device.
[0034] According to a second aspect of the invention, a base for the measuring device of the first aspect of the invention is provided, the base comprising an ultrasonic transducer driver and a first connector portion, the first connector portion being configured to enable attachment of the elongated stem to the base and to provide an electrical connection with the ultrasonic transducer of the elongated stem, the first connector portion comprising a first part of a coaxial electrical connector.
[0035] According to a third aspect of the invention, an elongated stem for the measuring device of the first aspect of the invention is provided, the elongated stem comprising an ultrasonic transducer and a second connector portion provided at its proximal end, the second connector portion being configured to enable attachment of the elongated stem to the base and to provide an electrical connection with the ultrasonic transducer driver of the base, the second connector portion comprising a second part of a coaxial electrical connector.
[0036] The present invention also extends to a stem extension member for use with an elongated stem as described above. The stem extension member is disposed between the base and the elongated stem and can extend the effective length of the elongated stem (e.g., enabling access to surfaces that are difficult to reach, such as deep bores or complex surfaces). The stem extension member may be an elongated body having a third connector portion provided at its proximal end and a fourth connector portion provided at its distal end. The third connector portion may be attachable to the first connector portion of the base, and the fourth connector portion may be attachable to the second connector portion of the elongated stem. Electrical connection may be provided through the stem extension member (i.e., enabling the transducer driver of the base to be electrically connected to the transducer of the elongated stem). The third and fourth connector portions may be identical to the second and first connector portions, respectively.
[0037] The present invention also extends to an ultrasonic measurement kit for an industrial measurement device and includes a plurality of elongated stems according to a third aspect of the present invention. Each elongated stem may have a different length and / or a different ultrasonic transducer configuration. The kit may also include a base. Thus, the kit enables different elongated stems to be attached to the base as needed, thereby enabling various different measurement tasks to be performed using the ultrasonic measurement device. The present invention also extends to a method including the step of attaching an elongated step to a base.
[0038] Accordingly, an ultrasonic measuring device is described herein. The ultrasonic measuring device may also be referred to as an ultrasonic measuring probe. The ultrasonic measuring device may be configured to be used with an industrial measuring device. The industrial device may include a coordinate positioning machine such as a CMM or a machine tool. The device may include a base (which may also be referred to as a base unit). The base may include an ultrasonic transducer driver (which may also be referred to as an ultrasonic transducer electronic circuit or an ultrasonic control module). The ultrasonic transducer driver may include a processor for controlling the ultrasonic transducer. The device may include an elongated stem. The elongated stem may also be referred to as a stylus. The elongated stem may include the ultrasonic transducer. The device may also include a connector assembly (or simply a connector). The connector assembly may be configured to removably attach the elongated stem to the base. The connector assembly may include a first connector portion provided on the base. The connector assembly may include a second connector portion provided on the elongated stem. The second connector portion may be provided at the proximal end of the elongated stem. When connected, the first and second connector portions may provide a mechanical alignment of the elongated stem with respect to the base. When connected, the first and second connector portions may provide an electrical connection between the ultrasonic transducer and the ultrasonic transducer driver. Any one or more of these features and / or other features described in this application may be provided.
[0039] Also, in this specification, an ultrasonic measuring device for an industrial measuring device includes a base provided with an ultrasonic transducer driver, an elongated stem provided with an ultrasonic transducer, and a connector assembly for releasably attaching the elongated stem to the base. The connector assembly includes a first connector portion provided on the base and a second connector portion provided at the proximal end of the elongated stem. When the first and second connector portions are connected, they provide mechanical alignment of the elongated stem with respect to the base and provide an electrical connection between the ultrasonic transducer and the ultrasonic transducer driver. The ultrasonic measuring device may include any one or a combination of the features described herein.
Brief Description of the Drawings
[0040] Here, the present invention will be described by way of example only with reference to the accompanying drawings.
Figure 1
Figure 2a
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[0041] Referring to FIG. 1, a machine tool is shown. The machine tool includes a housing 2 that includes a spindle 4 movable relative to a bed 3. The spindle 4 can move relative to the bed 3 under the control of a computer numerical controller (CNC) 6. To cut or process an object 8 disposed on the machine tool bed 3, the spindle can carry a cutting tool (not shown). A measurement sensor can also be attached to the spindle 4 in place of the cutting tool to enable the object 8 to be measured before or after a cutting procedure. Typically, such a measurement sensor and tool can be automatically loaded onto the spindle 4 under the control of the CNC 6 to enable a desired cutting and measurement sequence to be implemented. In FIG. 1, an ultrasonic measurement device 10 attached to the spindle 4 is shown. The measurement information is wirelessly transmitted (e.g., via an optical link or a wireless link) to an interface 12 that transfers such measurement values to the machine tool controller 6. As will be described below, the ultrasonic measurement device 10 enables internal characteristics of the object 8, such as the thickness of the object, to be measured.
[0042] Although a machine tool is shown in FIG. 1, the ultrasonic measurement device of the present invention can also be configured to be used with other coordinate positioning devices, such as a coordinate measuring machine (CMM), an industrial inspection robot, etc.
[0043] Referring to FIGS. 2a, 2b, and 2c, the appearance of the ultrasonic measurement device of the present invention is shown. In particular, FIG. 2a shows a base 20 and an elongated stem 22 of the ultrasonic measurement device 24 of the present invention. FIG. 2b shows a view of the distal end of the base 20 from the plane G-G shown in FIG. 2a, and FIG. 2c shows a view (on a differential scale) of the proximal end of the elongated stem 22 from the plane H-H shown in FIG. 2a.
[0044] The base 20 has a spigot 26 at its proximal end, by which it can be connected to a tool shank that can then be held in the spindle of a machine tool. The distal end of the base 20 comprises a first connector portion 28. The base 20 also comprises a high frequency (RF) transparent portion that enables the passage of RF signals between it and a spread spectrum (e.g., frequency hopping) RF communication module 25 located within the base 20. The transducer driver 29 is also disposed within the base 20, along with a set of batteries 27 that can be accessed via a battery cover 30.
[0045] The elongate stem 22 includes a coupling element 32 that projects at its distal end, which is acoustically coupled to a transducer 33 located within the elongate stem 22. A datum surface 34 is also provided at the distal end of the elongate stem adjacent to the coupling element 32. A second connector portion 36 is provided at the proximal end of the elongate stem 22, which comprises a rotatable collar 38.
[0046] Figure 2b shows an end view of the distal end of the base 20. It can be seen that the housing 40 of the base has a circular cross-section that is concentrically arranged with the first connector portion 28. The first connector portion 28 comprises an externally threaded casing member 42 and a female coaxial electrical connector socket 44.
[0047] Figure 2c shows an end view of the proximal end of the elongate stem 22 including the second connector portion 36. A male coaxial electrical connector plug 46 is shown together with a member 48 that forms part of the elongate stem 22 and an internally threaded collar 38 that is rotatable relative to the remainder of the elongate stem 22.
[0048] Referring to FIGS. 3 and 4, a longitudinal section through the base 20 and the elongated stem 22 is shown. FIGS. 3 and 4 show the base 20 and the elongated stem 22 in a non-attached state and an attached state, respectively, and the inset in the figure shows an enlarged view of the connector assembly, which is a combination of a first connector portion 28 and a second connector portion 36.
[0049] The female coaxial electrical connector socket 44 of the first connector portion 28 and the male coaxial electrical connector plug 46 of the second connector portion 36 are shown to be disposed on a central (longitudinal) axis 50. The outer threaded casing of the first connector portion 36 includes a threaded region 52 and is substantially coaxial with the female coaxial electrical connector socket 44. The collar 38 of the second connector portion 36 is rotatably connected to the remainder of the elongated stem 22 and is dimensioned such that the threads formed on the inside of the collar 38 can engage the threaded region 52 of the outer threaded casing of the first connector portion 28. The first connector portion 28 also includes a first reference plane 54, and the second connector portion 36 includes a second reference plane 56.
[0050] In the "attached" configuration shown in FIG. 4, the female coaxial electrical connector socket 44 engages the male coaxial electrical connector plug 46, thereby providing an electrical connection. The first reference plane 54 and the second reference plane 56 are also physically engaged, thereby defining the mechanical orientation of the elongated stem 22 with respect to the base 20. The female coaxial electrical connector socket 44 and the male coaxial electrical connector plug 46 can each be freely moved laterally a small amount relative to the remainder of their respective first and second connector portions. This prevents the relative positions of the two portions of the electrical connector from being constrained by the physical alignment provided by the first and second reference planes 54 and 56.
[0051] Next, referring to FIGS. 5a through 5d, a process for making a physical and electrical connection between the first connector portion and the second connector portion is shown.
[0052] Figure 5a shows the first and second connector portions 28 and 36 aligned with respect to each other before a physical and electrical connection is made between the elongated stem 22 and the base 20.
[0053] Figure 5b shows the first stage of the attachment process. The user inserts the male coaxial electrical connector plug 46 of the second connector portion 36 into the female coaxial electrical connector socket 44 of the first connector portion 28.
[0054] Figure 5c shows how further longitudinal movement is provided until the first and second reference planes 54 and 56 of the first and second connector portions 28 and 36 engage. At this stage, the frictional engagement between the male coaxial electrical connector plug 46 and the female coaxial electrical connector socket 44 means that the elongated stem 22 is loosely held in place.
[0055] Figure 5d shows the elongated stem 22 firmly fixed to the base 20 after the collar 38 has been rotated. In particular, the collar rotation fully engages and then firmly engages and holds the first and second reference planes 54 and 56. Importantly, the degree of freedom for the male coaxial electrical connector plug 46 and the female coaxial electrical connector socket 44 to move laterally means that the electrical connection is established without imposing a burden on the coaxial connector, thereby preventing degradation of the electrical connection.
[0056] Removal of the elongated stem 22 from the base 20 is achieved by reversing the above steps.
[0057] Those skilled in the art will understand the various alternatives and modifications to the configuration described above. For example, the shape and relative dimensions of the base and the elongated stem can be changed, and additional electrical or mechanical connections can be provided.
Claims
1. An ultrasonic measuring device for industrial measuring equipment, A base including an ultrasonic transducer driver, A slender stem equipped with an ultrasonic transducer, A connector assembly for releasably mounting the elongated stem to the base, the connector assembly comprising a first connector portion provided on the base and a second connector portion provided on the proximal end of the elongated stem, wherein the first and second connector portions, when connected, provide mechanical alignment of the elongated stem with respect to the base and provide an electrical connection between the ultrasonic transducer and the ultrasonic transducer driver, An ultrasonic measuring device characterized in that the connector assembly comprises a coaxial electrical connector that enables the electrical connection between the ultrasonic transducer and the ultrasonic transducer driver to be established together with the elongated stem fixed to the base in any rotational direction about the longitudinal axis of the elongated stem.
2. The ultrasonic measuring apparatus according to claim 1, wherein the first connector portion comprises a first reference surface, and the second connector portion comprises a second reference surface, and the engagement of the first and second reference surfaces provides orientation alignment of the elongated stem with respect to the base when the first and second connector portions are connected.
3. The ultrasonic measuring apparatus according to claim 2, wherein the distal end of the elongated stem includes a datum surface for ultrasonic measurement, and the datum surface is pre-aligned with respect to the second reference surface of the second connector portion.
4. The ultrasonic measuring apparatus according to claim 2 or 3, wherein the connector assembly comprises an operable locking mechanism for releasably locking the engagement of the first and second reference surfaces.
5. The ultrasonic measuring apparatus according to claim 4, wherein the operable locking mechanism comprises an internal threaded collar for engaging with at least one external threaded portion of the first and / or second connector portion.
6. The ultrasonic measuring device according to claim 1, wherein the connector assembly is axially symmetric.
7. The ultrasonic measuring apparatus according to claim 1, wherein the coaxial electrical connector assembly comprises a coaxial electrical connector having a first part and a second part, the first connector part comprising the first part of the coaxial electrical connector, and the second connector part comprising the second part of the coaxial electrical connector.
8. The ultrasonic measuring apparatus according to claim 7, wherein the first portion of the coaxial electrical connector is movable laterally with respect to the base, and / or the second portion of the coaxial electrical connector is movable laterally with respect to an elongated stem.
9. The ultrasonic measuring apparatus according to claim 7, wherein the first and second portions of the coaxial electrical connector engage by a push-fit action.
10. The ultrasonic measuring apparatus according to claim 1, wherein the connector assembly comprises one or more seals for preventing the ingress of fluid when the first and second connector portions are connected to each other.
11. The ultrasonic measuring apparatus according to claim 1, wherein the base comprises one or more batteries and a wireless communication unit for wirelessly transmitting measurement data derived from the ultrasonic transducer to a remote interface.
12. A base for a measuring device according to claim 1, the base comprising an ultrasonic transducer driver and a first connector portion, the first connector portion being configured to allow mounting of an elongated stem to the base and to provide an electrical connection of the elongated stem to the ultrasonic transducer, the first connector portion comprising a first portion of a coaxial electrical connector.
13. An elongated stem for a measuring device according to claim 1, the elongated stem comprising an ultrasonic transducer and a second connector portion provided at its proximal end, the second connector portion being configured to allow the elongated stem to be mounted on a base and to provide an electrical connection between the base and the ultrasonic transducer driver, the second connector portion comprising a second portion of a coaxial electrical connector.
14. A stem extension member for an elongated stem according to claim 13, wherein the stem extension member comprises an elongated body having a third connector portion provided at its proximal end and a fourth connector portion provided at its distal end, the third connector portion being attachable to the first connector portion of the base, and the fourth connector portion being attachable to the second connector portion of the elongated stem.
15. An ultrasonic measuring kit for industrial measuring devices, wherein the kit comprises a plurality of elongated stems according to claim 13, each having a different length and / or different ultrasonic transducer configuration.