阅读说明：本技术 计量设备以及制造方法 (Metrology apparatus and method of manufacture ) 是由 乔纳森·哈克特 于 2020-03-16 设计创作，主要内容包括：本文描述了计量设备以及制造用于计量设备的滑架组件的方法。滑架组件被配置为支撑测量探针。滑架组件包括：孔,被配置为收容具有纵轴的基准轨,并且被配置为允许基准轨从孔中滑过；通道,被配置为收容具有纵轴的导轨,并且被配置为允许导轨从通道中滑过,其中,导轨平行于基准轨。孔和通道中的至少一个包括与滑架组件一体形成的偏置装置,该偏置装置用于禁止滑架组件在除了沿基准轨或导轨的对应纵轴以外的方向上相对于对应的基准轨或导轨移动。(Metrology apparatus and methods of manufacturing a carriage assembly for a metrology apparatus are described herein. The carriage assembly is configured to support a measurement probe. The carriage assembly includes: a bore configured to receive a reference rail having a longitudinal axis and configured to allow the reference rail to slide through the bore; a channel configured to receive a rail having a longitudinal axis and configured to allow the rail to slide therethrough, wherein the rail is parallel to the reference rail. At least one of the aperture and the channel includes a biasing means integrally formed with the carriage assembly for inhibiting movement of the carriage assembly relative to the corresponding reference rail or guide rail in directions other than along the corresponding longitudinal axis of the reference rail or guide rail.)

1. A carriage assembly for a metrology apparatus, the carriage assembly configured to support a measurement probe, the carriage assembly comprising:

a bore configured to receive a reference rail having a longitudinal axis, the bore further configured to allow the reference rail to slide therethrough;

a channel configured to receive a rail having a longitudinal axis, the channel further configured to allow the rail to slide therethrough, wherein the rail is parallel to the reference rail; and

wherein at least one of the aperture and the channel includes a biasing means integrally formed with the carriage assembly for inhibiting movement of the carriage assembly relative to the corresponding reference rail or guide rail in directions other than along the longitudinal axis of the corresponding reference rail or guide rail.

2. The carriage assembly of claim 1, wherein the carriage assembly is formed from a single unitary piece.

3. The carriage of any preceding claim, wherein the aperture, channel, and biasing means are formed from the same material.

4. The carriage assembly of any preceding claim, wherein the carriage assembly is configured to:

(i) connecting to a moving means for moving the carriage assembly along the reference rail and the guideway; and

(ii) simultaneously biasing the reference rail and the guide rail in one direction and allowing the respective reference rail and the guide rail to slide in a lateral direction through the respective apertures and the channels when the carriage assembly is moved by the moving device.

5. The carriage assembly of claim 4, wherein the carriage assembly supports a measurement probe, wherein the measurement probe is configured to move as the carriage assembly moves along the reference rail and the guide rail.

6. The carriage assembly of any preceding claim, wherein the biasing means comprises at least one spring arm.

7. The carriage assembly of any preceding claim, wherein the aperture has at least one longitudinal groove on an inner surface thereof.

8. The carriage assembly of any preceding claim, wherein the aperture comprises a first biasing arrangement configured to inhibit rotation of the carriage assembly about an axis transverse to the longitudinal axis of the reference rail such that the reference rail is fixed by the aperture but configured to slide within the aperture.

9. The carriage assembly of any of the preceding claims, wherein a horizontal axis of the carriage assembly passes through the aperture and the channel, and wherein the channel includes a second biasing device configured to bias the rail in the channel, wherein at least one component of the bias from the second biasing device of the channel is in a direction transverse to the horizontal axis and transverse to the longitudinal axis of the rail.

10. The carriage assembly of claim 9, wherein the channel of the carriage assembly further comprises a guide pad opposite the second biasing device, wherein the guide pad and the second biasing device are each integrally formed with the carriage assembly, and wherein the guide pad and the second biasing device are configured to contact the rail and allow the rail to slide between the guide pad and the second biasing device when in use.

11. The carriage assembly of any preceding claim, wherein the carriage assembly is configured to be connected to a moving device for sliding the carriage assembly along the reference rail and the guide rail.

12. The carriage assembly of claim 11, wherein the channel and the aperture are connected by a front panel extending therebetween, wherein the front panel includes a slot for removably connecting the carriage assembly to the mobile device.

13. A carriage assembly for a metrology apparatus, the carriage assembly configured to support a measurement probe, the carriage assembly comprising:

a bore configured to receive a reference rail and to allow the reference rail to slide therethrough, wherein the reference rail has a longitudinal axis;

wherein the aperture includes a first biasing device configured to bias the reference rail into a receptacle within the aperture, wherein the receptacle is configured to inhibit rotation of the carriage assembly about an axis transverse to the longitudinal axis of the reference rail such that the reference rail is fixed by the aperture but configured to slide within the aperture.

14. The carriage assembly of claim 13, wherein the carriage assembly further comprises a channel configured to receive the rail and allow the rail to slide therethrough, wherein the rail further has a longitudinal axis parallel to the longitudinal axis of the reference rail;

wherein a horizontal axis of the carriage assembly passes through the aperture and the channel; and

wherein the receptacle is configured to inhibit rotation of the carriage assembly about the horizontal axis.

15. The carriage assembly of claim 14, wherein at least one component of the bias of the first biasing device is in a direction parallel to the horizontal axis.

16. The carriage assembly of claim 9, 14 or 15, wherein the first biasing arrangement comprises a pair of biasing arrangements arranged spaced apart along at least a portion of the length of the reference rail to inhibit rotation of the carriage assembly about the plane in the horizontal axis.

17. The carriage assembly of claim 8 or any claim dependent thereon, or any one of claims 13 to 16, wherein the first biasing device is configured to bias the reference rail into a receptacle configured to inhibit movement of the reference rail in a direction other than along the longitudinal axis.

18. The carriage assembly of claim 9 or 14 or any claim dependent thereon, wherein the first biasing device is configured to bias the reference rail into the receptacle in a direction parallel to the horizontal axis of the carriage assembly.

19. The carriage assembly of claim 17 or 18, wherein the receptacle is generally v-shaped to provide at least two points of contact with the reference rail.

20. The carriage assembly of claim 17, 18, or 19, wherein the receiving portion provides at least three contact points with the reference rail in addition to the contact points provided by the first biasing device.

21. The carriage assembly of any of claims 17-20, wherein the aperture extends along at least a portion of the longitudinal axis, and wherein the aperture comprises at least two receivers, each receiver disposed proximate a respective end of the aperture along the portion of the longitudinal axis.

22. The carriage assembly of any of claims 14-21, wherein the channel includes a second biasing device configured to bias the rail in the channel, wherein at least one component of the bias from the second biasing device is in a direction transverse to the horizontal axis and transverse to the longitudinal axis of the rail.

23. The carriage assembly of any of the preceding claims, wherein the aperture extends a distance along the longitudinal axis of the reference rail that is greater than a distance that the channel extends along the longitudinal axis of the guide rail.

24. A metrology apparatus for measuring the surface of a workpiece, comprising:

the carriage assembly of any of the preceding claims;

a reference rail located within the channel;

a guide rail positioned within the bore;

a moving device detachably connected to the carriage assembly; and

a measurement probe mounted on the carriage apparatus, configured to move as the carriage assembly moves along the reference rail and the guide rail, and measure a surface roughness of a workpiece.

25. A method of manufacturing a carriage assembly according to any of the preceding claims by injection moulding, comprising the steps of:

positioning a mold of the carriage assembly to a first position;

feeding a first material into the mold, wherein the first material is in a molten state and is suitable for injection molding;

curing the first material within the mold of the carriage assembly; and

removing the carriage assembly from the mold of the carriage assembly.

Technical Field

The present invention relates to a carriage assembly (also known as a carriage assembly) for a metrology apparatus, a metrology apparatus comprising the carriage assembly, and a method of manufacturing the carriage assembly.

Background

Some types of metrology apparatus (e.g. surface measurement instruments) include a measurement probe for following the surface of the workpiece and a sensor responsive to surface features (e.g. texture or shape) to provide a signal dependent on the movement of the measurement probe. To follow the surface of the workpiece, it is desirable to configure the metrology apparatus in a manner that minimizes systematic or random errors.

The S-100 series surface roughness tester is an example of a metrology tool configured to perform surface measurements on a workpiece. S100 includes a measurement probe mounted on a carriage assembly that slides along a reference rail (datum rail) and a guide rail (guide rail). The carriage assembly is made of several parts (see fig. 1 and 2 and the description below) and these parts are precisely arranged to effectively connect together.

Arranging these parts and manufacturing in this mannerThe S-100 carriage assembly is time consuming and complex, particularly because the components (e.g., bushings) around the reference rail need to be carefully aligned so that the carriage assembly can slide smoothly along the reference rail. Furthermore, if any errors are made during the manufacturing process, this may result in systematic errors in the metrology measurements.

Thus, a problem with the prior art is the time, complexity, and difficulty associated with assembling the carriage assembly. Embodiments of the present disclosure may seek to mitigate these problems.

Disclosure of Invention

Aspects of the invention are set out in the appended claims. Optional features are given in the dependent claims.

In this example, the inventors have realized that while the various portions of the carriage assembly are very functionally distinct (sometimes contradictory — e.g., providing rigid support and providing a biasing force), these various portions can be made integral and still perform contradictory functions. For example, the structure of the carriage assembly needs to be rigid to support the measurement probe, constrain the rotation of the carriage assembly relative to the rail, and obtain linear movement along the reference rail to perform accurate metrology measurements, while the structure of the carriage assembly also needs to be flexible, for example to accommodate the rail and/or the reference rail.

According to a first aspect of the present disclosure, there is provided a carriage assembly for a metrology apparatus, the carriage assembly being configured to support a measurement probe for measuring a surface of a workpiece. The carriage assembly includes an aperture configured to receive the reference rail and allow the reference rail to slide therethrough, and a channel configured to receive the guide rail and allow the guide rail to slide therethrough, wherein the guide rail is parallel to the reference rail. At least one of the aperture and the channel includes a biasing device integrally formed with the carriage assembly. Optionally, the biasing means may be configured to inhibit movement of the carriage assembly relative to the corresponding reference rail or guide rail in directions other than along the corresponding longitudinal axis of the reference rail or guide rail (e.g. one direction, or in some examples, all directions).

In use, because the carriage assembly 310 supports the measurement probe 350, the carriage assembly 310 needs to be relatively rigid. The unitary structure of the example carriage assembly 310 of the present disclosure provides other benefits, such as making the design of a desired stiffness so that the carriage assembly 310 is relatively stiff.

Furthermore, by integrally forming the running surface (i.e., the inner surface of the channel and bore) into the carriage assembly, these surfaces are inherently aligned, thus eliminating the need for settling (setting) and subsequent gluing (gluing).

Alternatively, the carriage assembly including the biasing means may be formed from a single integral piece. Further alternatively, the holes, channels, and/or biasing means may be formed from the same material. Alternatively, the material may be Polyetheretherketone (PEEK), alternatively the material may be reinforced with carbon fibres, and/or alternatively the material may further comprise Polytetrafluoroethylene (PTFE).

In some examples, the aperture includes a first biasing device configured to inhibit rotation of the carriage assembly about an axis transverse to a longitudinal axis of the reference rail such that the reference rail is fixed by the aperture but configured to slide within the aperture.

The horizontal axis of the carriage assembly passes through the aperture and the channel. In some examples, the channel includes a second biasing device configured to bias the rail in the channel. At least one component of the bias from the second biasing means of the channel may be in a direction transverse to the horizontal axis and transverse to the longitudinal axis of the rail.

The channel of the carriage assembly may further comprise a guide pad opposite the second biasing means. The guide pad and the second biasing device may each be integrally formed with the carriage assembly. In use, the guide pad and the second biasing means may be configured to contact the guide rail and allow the guide rail to slide between the guide pad and the second biasing means. Alternatively, the guide pad may be shaped to allow the carriage assembly to move along the rail and reduce friction between the guide pad and the rail. For example, the guide pad may be configured to contact the guide rail with an at least partially circular surface. The guide pad may be long enough to maintain rigidity and stability, but short enough so that its contact is actually a point contact, thus limiting the rotation of the carriage about the reference rail only, without affecting the straightness of the movement. To this end, the fixed/rigid side of the guide pad contacts the guide rail with a cylindrical surface, the axis of which intersects the guide rail axis, thus creating a single point of contact. The contact surface of the second biasing means may be rounded so that when frictional resistance applies a torque to each beam (beam) during movement to cause it to rotate, the second biasing means still presents the same surface shape to the guide rail.

In some examples, the carriage assembly may be configured to be coupled to a moving device configured to move the carriage assembly along the reference rail and the guide rail. The carriage assemblies may be configured to simultaneously bias the reference rails or tracks in one direction and allow the respective reference rail or track to slide through the corresponding aperture or channel in a lateral direction as the carriage assemblies are moved by the moving device. For example, the biasing means may be configured to simultaneously bias the reference rails or tracks and allow the respective reference rails or tracks to slide through the corresponding apertures or channels when the carriage assembly is moved by the moving means.

The moving means may be any device adapted to provide a force to the carriage assembly to force the carriage assembly to move along the reference rail and the guide rail. The moving means may include a motor, an engine, a system for moving weights, a pulley system, or any other suitable means for moving the carriage assembly along the rails and the reference rail.

The carriage assembly may include an interface (e.g., slot) for receiving a mobile device. The interface may be configured to releasably connect to a mobile device. For example, the carriage assembly may include a front panel connecting the channel and the aperture. The front panel may include a slot for receiving the mobile device such that the carriage assembly may be removed from the mobile device (e.g., for maintenance or inspection).

It will be appreciated that the carriage assembly may support the measurement probe, and the measurement probe may be configured to move with the carriage assembly as the carriage assembly moves along the reference rail and the guide rail. For example, the displacement of the carriage assembly along the reference rail and the guide rail may be equal to the displacement of the measurement probe. The measurement probe may be adapted to measure the surface roughness, surface conductance, or other surface properties of the workpiece. In some examples, relative movement of the carriage assembly along the reference rail may be measured to determine displacement of the measurement probe. Movement of the carriage assembly along the reference rail may be determined using sensors and/or based on energy provided to the mobile device (e.g., current provided to the mobile device).

In some examples, the measurement probe may be configured to measure the workpiece by moving in a direction perpendicular and/or parallel to the longitudinal axis of the reference and guide rails. The measurement probe may be configured to passively track a surface height of the workpiece as the carriage assembly moves along the reference rail and the guide rail.

The biasing means may be any means suitable for providing a force to the rail and/or the reference rail such that the rail and/or the reference rail is securely supported by the carriage assembly (e.g., such that the rail and/or the reference rail have an interference fit with the respective channels and holes). The biasing means may be in the form of or act as a spring arm. The spring arms may be integrally formed with the carriage assembly, and in some examples, the spring arms may be made of the same material as the rest of the carriage assembly. However, it will be appreciated that in some examples the biasing means may be in the form of a different type of spring, or resilient element, or any other suitable means.

Optionally, the bore has at least one longitudinal groove disposed along an inner surface thereof. Advantageously, the longitudinal grooves may allow any wear particles (wear particles) to migrate along the grooves and away from any active surface (i.e., away from any contact point between the reference rail and the carriage assembly).

The distance that the aperture extends along the longitudinal axis of the reference rail may be greater than the distance that the channel extends along the longitudinal axis of the guide rail. Further optionally, the hole extends along the longitudinal axis of the reference rail a distance at least three times greater than the distance the channel extends along the longitudinal axis of the guide rail.

Optionally, the carriage assembly includes a reinforcing strip that may extend between the aperture and the channel. Further optionally, the carriage assembly comprises a second reinforcing strip, which may extend at least partially along the length of the reference rail and/or the length of the aperture. The stiffening strip may increase the stiffness of the carriage assembly and thus the accuracy of measurements performed by the metrology apparatus in which the carriage assembly is used.

According to a second aspect of the present disclosure, there is provided a carriage assembly for a metrology apparatus, the carriage assembly being configured to support a measurement probe for measuring a surface of a workpiece. The carriage assembly includes an aperture configured to receive the reference rail and allow the reference rail to slide therethrough. The bore includes a first biasing device configured to bias the reference rail into a receptacle within the bore. The reference rail has a longitudinal axis, and the receptacle is configured to inhibit rotation of the carriage assembly about an axis transverse to the longitudinal axis of the reference rail such that the reference rail is secured by the aperture but is configured to slide within the aperture. In some examples, the receptacle is configured to inhibit movement of the reference rail in a direction other than along the longitudinal axis. At least one component of the bias of the first biasing means may be in a direction parallel to the horizontal axis.

Optionally, the receptacle is generally v-shaped to provide at least two points of contact with the reference rail. Optionally, the receiving portion provides at least three contact points with the reference rail in addition to the contact points provided by the first biasing means. Providing such a receptacle configured to receive means that the carriage assembly 310 can slide smoothly along the reference rail 322 regardless of orientation (e.g., whether upright or upside down).

Optionally, the first biasing means may comprise a pair of biasing means arranged spaced apart along at least a portion of the length of the reference rail to inhibit rotation of the carriage assembly about the plane in the horizontal axis. The first biasing device may be configured to bias the reference rail into the receptacle in a direction parallel to a horizontal axis of the carriage assembly. In examples where the first biasing means comprises a pair of biasing means, the force exerted by each of the pair of biasing means is not necessarily the same as the other, since the opposing forces of the pair of biasing means are not equal. The combination of forces (weight and friction) from the guide rail and/or the reference rail and drag torque (drag torque) means that the total force at each end of the carriage assembly may be different. Likewise, if the first biasing means comprises only one biasing means, the position of the biasing means acting on the reference rail may be off-centre to balance torque and force.

In some examples, the aperture extends along at least a portion of the longitudinal axis, and wherein the aperture includes at least two receptacles, each receptacle being disposed proximate a respective end of the aperture along the portion of the longitudinal axis. In other examples, the receptacle extends along the length of the bore in the longitudinal direction.

In some examples, the carriage assembly further comprises a channel configured to receive the rail and allow the rail to slide therethrough. The guide rail also has a longitudinal axis parallel to the longitudinal axis of the reference rail. A horizontal axis of the carriage assembly passes through the aperture and the channel, and the receiving portion is configured to inhibit rotation of the carriage assembly about the horizontal axis.

Alternatively, at least one component of the bias of the first biasing means may be in a direction parallel to the horizontal axis. Alternatively, the first biasing means may be any means adapted to provide a force to the reference rail such that the reference rail fits snugly within the bore (e.g. to prevent movement of the reference rail within the bore in any direction other than along the longitudinal axis of the reference rail), while allowing movement of the carriage assembly along the reference rail. For example, the first biasing means may be a spring, such as a spring arm or a pair of spring arms, or may be a resilient element or any other suitable means. The first biasing means may allow the carriage assembly to self-compensate for the amount of wear that may occur in use.

The channel may include a second biasing device configured to bias the rail in the channel, wherein at least one component of the bias from the second biasing device is in a direction transverse to the horizontal axis and in a direction transverse to the longitudinal axis of the rail. The second biasing means may be integrally formed with the carriage assembly. Incorporating the biasing apparatus into the carriage assembly may eliminate the need to connect (e.g., screw) the biasing apparatus to the carriage assembly. This can reduce the number of points where a greater amount of wear is expected, as well as reduce manufacturing time and cost. In addition, the second biasing means may also allow the carriage assembly to self-compensate for the amount of wear that may occur in use.

The carriage assembly may be configured to be coupled to a moving device configured to move the carriage assembly along the reference rail. Alternatively, the moving means may be any device adapted to provide a force to the carriage assembly to force the carriage assembly to move along the reference rail.

Alternatively, the moving means may comprise a motor, an engine, a system for moving weights, a pulley system, or any other suitable means.

According to a third aspect of the present disclosure, a metrology apparatus for measuring a surface of a workpiece is provided. The metrology apparatus comprises a carriage assembly (e.g. as described above with reference to the first and/or second aspects), a reference rail located within the channel, a guide rail located within the bore, a movement device removably connected to the carriage assembly, and a measurement probe mounted on the carriage apparatus, the measurement probe being configured to move as the carriage assembly moves along the reference rail and the guide rail and to measure the surface roughness of the workpiece.

According to a fourth aspect of the present disclosure, there is provided a method of manufacturing a carriage assembly (e.g. the carriage assembly described above with reference to the first and/or second aspect) by injection moulding (e.g. by closed moulding). The method may comprise the steps of: positioning a mold of the carriage assembly to a first location, feeding a first material into the mold, wherein the first material is in a molten state and suitable for injection molding, solidifying the first material within the mold of the carriage assembly, and removing the carriage assembly from the mold of the carriage assembly.

Drawings

FIG. 1 shows a perspective view of a prior art metering apparatus;

FIG. 2 shows a perspective view of a carriage assembly, a measurement probe, and guide and reference rails used in the prior art metrology device of FIG. 1;

FIG. 3 illustrates a perspective view of an example carriage assembly of an embodiment of the present disclosure;

FIG. 4 illustrates an end view of the example carriage assembly of FIG. 3;

FIG. 5 illustrates a top view of the example carriage assembly of FIGS. 3 and 4;

FIG. 6 shows a perspective view of the example carriage assembly of FIGS. 3, 4, and 5 connected to a measurement probe, a guide rail, and a reference rail;

fig. 7 is a flow chart illustrating steps for manufacturing a carriage assembly (e.g., the example carriage assembly of fig. 3-6).

Detailed Description

FIG. 1 shows the prior art discussed in the background aboveS-100 series surface roughness tester metering equipment. The metering device 100 includes a housing 125 carrying a user interface including a screen and a user control module including one or more buttons. Extending from the bore 127 in the housing 125 is a measurement probe 150. The measurement probe 150 is connected by a shaft 152 to a carriage assembly 210 contained within the housing 125. Metering device100 may also contain within housing 125 a control module including a processor, data storage, and power devices. The power device may include a source that stores energy, or may be a device that receives energy from an external source. The metrology apparatus 100 may also include a movement device 226 within the housing 125 for moving the measurement probe 150 via the carriage assembly 210, the movement device 226 being driven by the power device and controlled by the control module.

Fig. 2 shows a prior art carriage assembly 210. The body of the carriage assembly 210 is formed in an L-shaped configuration. The carriage assembly includes an aperture 214 for receiving a reference rail 222 and a channel 225 for receiving a rail 224. A channel 225 and an aperture 214 are formed in the front panel 205 on one side of the L-shape, the aperture 214 extending through the carriage assembly 210 along the length of the other side of the L-shape.

The front panel 205 of the carriage assembly 210 is further connected to the movement device 226 and the measurement probe 150 by a shaft 152 extending through a full circular hole in the front panel 205, so the bottom of the hole prevents the carriage assembly 210 from being removed unless the movement device (adhered to the housing 125) is removed with the carriage assembly 210.

The carriage 210 assembly is formed from multiple components. For example, two sliding bushings are glued to opposite ends of the bore 214 to allow the carriage assembly 210 to slide on the reference rail 22. Gluing the sliding bushings to the carriage assembly 210 typically takes at least 24 hours to ensure that the gluing is complete without bending the body of the carriage assembly 210 and that the two sliding bushings are properly aligned. The channel 225 also includes guide pads (which are also glued in place) for contacting the guide rails 224 and sliding on the guide rails 224, and leaf springs (leaf springs) for biasing the guide rails 224 against the guide pads.

However, as noted above, arranging these components and manufacturing the carriage assembly 210 in this manner is time consuming and complicated, particularly because the components, such as bushings around the reference rail 222, need to be carefully aligned so that the carriage assembly 210 can slide smoothly along the reference rail 222. Further, because the carriage assembly 210 is manufactured from multiple separate components, variations in design tolerances may cause the carriage assembly 210 to undesirably bend and flex, which may affect metrology measurements.

Fig. 3-6 illustrate an example of a carriage assembly 310 of an embodiment of the present disclosure. The carriage assembly 310 of fig. 3-6 has common functionality with the prior art examples shown in fig. 1 and 2 and discussed above.

However, in contrast to the carriage assembly 210 of fig. 1 and 2, the carriage assembly shown in fig. 3-6 is constructed from a single unitary piece, which in this example is an injection molded plastic, such as Polyetheretherketone (PEEK), optionally reinforced with carbon fiber, and/or optionally further comprising Polytetrafluoroethylene (PTFE).

As with the prior art example, the body of the carriage assembly 310 shown in FIG. 3 is formed in an L-shaped configuration. The carriage assembly 310 includes an aperture 314 for receiving a reference rail 322 and a channel 325 for receiving a rail 324. A channel 325 and an aperture 314 are formed in the front panel 305 on one side of the L-shape, with the aperture 314 extending through the carriage assembly 310 along the length of the other side of the L-shape. The horizontal axis of the carriage assembly 310 passes through the aperture 314 and the passage 315. The channel 315 is generally U-shaped and forms a slot that allows the rail 324 to slide into the channel 315 in a direction along the horizontal axis.

Guide rail 324 is parallel to reference rail 322. Reference rail 322 has a longitudinal axis and guide rail 324 has a longitudinal axis. Because the length of the aperture 314 along the other side of the L-shape extends through the carriage assembly 310 (but the channel 315 does not), the aperture 314 extends a greater distance along the longitudinal axis of the reference rail 322 than the channel 315 extends along the longitudinal axis of the rail 324, and the aperture 314 itself has a longitudinal axis that passes through the carriage assembly 310.

The aperture 314 includes an integrally formed first biasing apparatus 375, the first biasing apparatus 375 being integrally formed with the body of the carriage assembly 310 (e.g., the first biasing apparatus 375 is a unitary structure with the carriage assembly 310). The aperture 314 also includes a receiving portion 377 opposite the first biasing apparatus 375, which in the illustrated example is approximately V-shaped, and forms two fixed contact points between the receiving portion 377 and the reference rail 322, with the first biasing apparatus 375 forming a third contact point with the reference rail 322. The third point, together with the two points described above, defines a moving contact plane with the reference rail 322, which plane holds the reference rail 322 at two fixed points. As can be seen in more detail in fig. 5, the first biasing device 375 comprises a pair of spring arms that are coupled together by a point approximately midway along a longitudinal axis through the aperture 314 of the carriage assembly 310 in the example shown. Four fixation points (two from the receptacles 377 (when the biasing means holds them on the reference rail 322) and two from the two arms of the first biasing means 375) provide a defined traverse direction and remove four degrees of freedom so that only translation along the reference rail 322 and rotation around the reference rail 322 is not restricted.

Channel 325 includes an integrally formed guide pad 326 opposite an integrally formed second biasing device 328. The orientation of the guide pad 326 and the integrally formed second biasing means 328 of the channel 325 relative to each other is transverse to the orientation of the first biasing means 375 and the receiving portion 377 of the aperture 314 relative to each other. In the example shown, the second biasing device 328 comprises a pair of spring arms, each spring arm extending parallel to the other arm in a direction parallel to the horizontal axis of the carriage assembly. Guide pad 326 of tunnel 325 provides a fifth point of contact and removes the fifth degree of freedom, leaving only the remaining degrees of freedom in the desired direction of travel.

The front panel 305 of the carriage assembly 310 includes an optional central U-shaped slot 340, the slot 340 extending to one side (in this example, the base) of the front panel 310 of the carriage assembly 310. The central notch 340 is reinforced by a slot reinforcement 341 that defines the notch 340.

In the example shown, the carriage assembly 310 includes an optional first stiffener 342, the first stiffener 342 extending between the aperture 314 and the channel 315, and in the example shown extending along the length of the front panel 305. In the example shown, the first stiffener 342 has a bent pin (dog-leg) proximate the hole 314, which in the example shown receives the central slot 340 and the slot stiffener 341. The bent pin shape has two functions. The bending pin retains the "spine" of material on the carriage assembly 310, which contributes to the overall stiffness of the material, while the bending pin itself allows the spine to push the leftmost V-shaped feature of the hole 314 as far as possible outside of the component. This provides the aperture 314 with as wide an area as possible to maximize its stability at the available length. The first reinforcing strip 342 may form at least a portion of the aperture 314 and/or the channel 315. In the example shown, the first reinforcing strip 342 provides half of the circumference of the aperture 314 and also provides half or one side of the channel 315 and extends the length of the channel 315 in the horizontal axis. One half of the circumference of the aperture 314 defined by the first reinforcing bar 342 is offset from the other half of the circumference of the aperture 314 along the longitudinal axis of the aperture 314 (and along the longitudinal axis of the reference rail 322 when in use) to define a telescopic shut-off.

First stiffening strip 342 also supports guide pad 326 of tunnel 325 proximate the end of first stiffening strip 342 and the end of tunnel 315 opposite second biasing device 328. In the example shown, the second biasing device 328 extends along one side of the channel 315 in a direction parallel to the direction in which the first stiffening strip 342 extends along the other side of the channel 315, and to the same extent that the first stiffening strip 342 extends along the other side of the channel 315. In the example shown, as shown in fig. 5, the first stiffener 342 extends along a horizontal axis between two spring arms of the second biasing device 328 such that each spring arm of the second biasing device 328 and the guide pad 326 connected to the first stiffener 342 are offset from each other along the longitudinal axis of the rail 324 in use to provide opposing moments on the rail 324.

The carriage assembly 310 also includes an optional second reinforcing bar 344, the second reinforcing bar 344 extending along the length of the bore 314 and parallel to the longitudinal axis of the reference rail 322 when in use. In the example shown, the first stiffener 342 is connected to the second stiffener 344 and has the same proportions (i.e., height and thickness).

Also shown in fig. 3-6 is a stop indicator post 320 integrally formed with the carriage assembly 310.

Hole 314 is configured to receive reference rail 322 and allow reference rail 322 to slide therethrough. Channel 325 is configured to receive rail 324 and allow rail 324 to slide therethrough.

The first biasing device 375 is configured to bias the reference rail 322 into the receptacle 377 in a direction parallel to the horizontal axis of the carriage assembly 310. The pair of spring arms of the first biasing device 375 are configured to apply a biasing force to the reference rail 322 at opposite ends of the aperture 314. The first biasing device 375 and the receiving portion 377 are configured to inhibit movement of the carriage assembly 310 relative to the corresponding reference rail 322 in directions other than along the corresponding longitudinal axis of the reference rail 322.

Second biasing means 328 is configured to bias guide rail 324 in a direction transverse to the horizontal axis and transverse to the longitudinal axis of guide rail 324, in use, towards guide pad 326.

It should be appreciated that the first biasing apparatus 375 and the second biasing apparatus 328 are sized such that if the carriage assembly 310 were inflexible, the reference rail 322 and the guide rail 324 would not fit in the gap. Thus, the first and second biasing devices 375, 328 inherently bear loads when flexed to accommodate the rails 322, 324, thereby providing an ever-present preload (preload) against weight and drag.

The front panel 305 of the carriage assembly 310 is configured to be connected to the movement device 326 and the measurement probe 350 via a shaft 352. In particular, as shown in fig. 6 and described in more detail below, the central notch 340 and the notch stiffener 341 are configured to allow removable connection to the movement apparatus 326 and/or the shaft 352 to which the measurement probe 350 is connected. This simplifies the assembly process of the metering apparatus including the carriage assembly and the moving means and facilitates easy removal of components of the metering apparatus for maintenance and inspection. For example, this means that the carriage assembly 310 can be removed from the housing while leaving the mobile device 326 in place.

In the example shown, the aperture 314 is not circular (rather, the aperture 314 is formed by two generally triangular halves to form an approximately diamond or parallelogram), and the first biasing device 375, along with the receiving portion 377, are configured to form a three-point kinematic connection with the reference rail 322. The first biasing device 375 is configured to bias the reference rail 322 to maintain the connection within the receptacle 377 in the aperture 314. Such a three-point kinematic connection may help inhibit movement of the carriage assembly 310 relative to the reference rail 322 in directions other than along the longitudinal axis of the reference rail 322 or about the longitudinal axis of the reference rail 322.

The channel 325 is configured to receive the rail 324. The second biasing arrangement 328 is configured to bias the rail 324 onto the guide pad 326 of the carriage assembly 310 in a direction transverse to the horizontal axis of the carriage assembly 310, transverse to the longitudinal axis of the aperture 314, and transverse to the longitudinal axes of the rail 324 and the reference rail 322, in use. The second biasing device 328 is also configured to bias the rail 324 onto the guide pad 326 of the carriage assembly 310 in a direction transverse to the biasing direction of the first biasing device 375.

The carriage assembly 310 is configured to slide along the rail 324 and the reference rail 322 along longitudinal axes of the rail 324 and the reference rail 322 (e.g., as implemented by the moving device 326). Thus, the carriage assembly 310 is configured to move easily in one degree of freedom (e.g., in one axis, such as an axis parallel to the longitudinal axis of the aperture 314 and the longitudinal axes of the guide rail 324 and the reference rail 322 in use), but to be inhibited from moving in all other degrees of freedom. The carriage assembly 310 may be configured to provide a low degree of friction with the guide rail 324 and the reference rail 322. For example, the carriage assembly 310 may be made of or include a proportion of a material having a low degree of friction with metal, such as Polyetheretherketone (PEEK) and/or Polytetrafluoroethylene (PTFE).

The receiving portion 377 of the aperture 314 is configured to inhibit rotation of the carriage assembly 310 about an axis transverse to the longitudinal axis of the reference rail 322 such that the reference rail 322 is secured by the aperture 314 but is configured to slide within the aperture 314. The receiving portion 377 and the first biasing apparatus 375 are configured such that the reference rail 322 may be used at greater tolerances than would otherwise be the case, such that an interference fit is still maintained between the bore 314 and the reference rail 322 after a certain degree of wear through continued use.

The alternative telescoping closed arrangement of the aperture 314 shown in the example of fig. 3-6 is configured to facilitate alignment of the reference rail 322 within the aperture 314. This means that sliding bushings are no longer required, which therefore simplifies the manufacturing process, since gluing bushings are not required. As mentioned above, the glue would otherwise take 24 hours to set, thus significantly reducing the manufacturing time of the carriage assembly 310. The telescoping closed design of the aperture 314 as shown in the example of fig. 3-6 may make injection molding of the carriage assembly 310 simpler and more efficient.

Stop indicator post 320 may be configured to prevent carriage assembly 310 from moving too far/out of range along reference rail 322 and/or as a zero reference for measurement so that relative displacement of carriage assembly 310 with respect to reference rail 322 may be measured. For example, the metering device may include a sensor (e.g., a light gate) for sensing the position of the stop indicator post 320.

In use, similar to the example described above with reference to fig. 1 and 2, the carriage assembly 310 of embodiments of the present disclosure is located within the housing of the metering device. The housing includes a guide rail 324 and a reference rail 322 connected to the housing. The carriage assembly 310 is mounted on the rails 324 and the reference rail 322 and supports a measurement probe 350 outside the housing by a shaft 352 extending through an aperture in the housing.

The carriage assembly 310 is coupled to a mover 326 and is driven by the mover 326 along a rail 324 and a reference rail 322. As with the prior art example described with reference to fig. 1 and 2, the mobile device 326 may be operated by a control module. Because the carriage assembly 310 supports the measurement probe 350, the measurement probe 350 moves (e.g., relative to the workpiece being measured) as the carriage assembly 310 moves along the reference rail 322 and the guide rail 324.

In some examples, the aperture 314 includes at least two receptacles 377. For example, each receiving portion 377 may be disposed proximate a respective end of the aperture 314 along a corresponding portion of the longitudinal axis of the reference rail 322.

The carriage assembly 310 may be formed of a single material (or may be formed of the same material mixture such that its structure is homogeneous), such that the aperture 314, the channel 325, and/or the biasing device 375, 328 may be formed of the same material. The carriage assembly 310 may be formed, for example, from Polyetheretherketone (PEEK). This may be reinforced by carbon fibres. Additionally or alternatively, the carriage assembly 310 may also comprise polytetrafluoroethylene.

In some examples, it is understood that the aperture 314 may not have a receptacle 377. For example, the aperture 314 may be substantially circular. In such an example, the aperture 314 may also not include the first biasing apparatus 375.

In some examples, the inner surface of the bore 314 may include one or more grooves. These grooves may extend through the holes. The recess may be configured such that any particles trapped in the aperture, particularly any particles trapped between the reference rail 322 and the aperture 314, are contained within the recess. As a result, these particles will cause less friction and/or wear between the reference rail 322 and the carriage assembly 310. By manipulating the carriage assembly 310 along the reference rail 322, it is also more likely that particles will be removed from the aperture 314 due to the presence of the groove. Note that while multiple grooves may be employed in some embodiments, only one groove may be required to achieve this effect. In some embodiments, the grooves may be equally spaced from each other, and in other embodiments, the grooves may be spaced at random intervals along the inner surface of the bore. Note that the presence of the groove is an optional feature of the integral carriage assembly 310.

Fig. 7 is a flow chart illustrating a method 700 for manufacturing a carriage assembly (e.g., the carriage assembly of fig. 3-6).

The method comprises the following steps: the mold for the carriage assembly is positioned 710 to a first location, a first material is fed 720 (e.g., injected) into the mold, the first material within the mold for the carriage assembly is cured 730, and the carriage assembly is removed 740 from the mold for the carriage assembly.

The mold may be made of a wear resistant material, such as a metal (e.g., aluminum or steel). Steel may be more wear resistant, but the use of aluminum may be less expensive. The material of the mold may be selected based on a number of technical and commercial considerations. The first material may be any material suitable for injection molding and may be in liquid form. For example, the material may be a thermoplastic, a thermoset, and an elastomer. The material may be an alloy or blend of materials. Common injection molding materials are nylon, polyethylene, and polystyrene. The material may be cured by lowering the temperature of the material below the melting point of the material or by a change in pressure.

Once the material is cured, the carriage assembly is formed. Removal of the carriage assembly may be achieved by a mold formed of two or more parts that may be disassembled so that the carriage assembly may be removed. For example, the mold may have ejector pins (ejectors pin) so that the mold can be opened easily, reliably, and quickly to allow removal of the carriage assembly.

It should be understood from the foregoing discussion that the embodiments illustrated in the figures are merely exemplary and include features that may be summarized, removed, or replaced as described herein and as given in the claims. Referring to the drawings in general, it should be understood that the functions of the systems and devices described herein are indicated using schematic functional block diagrams. It should be understood, however, that the functionality need not be divided in this manner, and should not be construed to imply any particular hardware architecture other than that described and claimed below. The functionality of one or more of the elements shown in the figures may be further subdivided and/or distributed throughout the apparatus of the present disclosure. In some embodiments, the functionality of one or more of the elements shown in the figures may be integrated into a single unit.

The above embodiments are to be understood as illustrative examples. Other embodiments are also contemplated. It is to be understood that any feature described in relation to any one embodiment may be used alone, or in combination with other features described, and may also be used in combination with one or more features of any other of the embodiments, or any combination of any other of the embodiments. Furthermore, equivalents and modifications not described above may also be employed without departing from the scope of the invention, which is defined in the accompanying claims.