# TPA2

# Overview

<span class="fontstyle0">Robust and compact shank mounted 5 way touch-trigger probe used for coordinate measuring machines (CMMs)</span>

[![Kurokesu-TPA2-1,2_.jpg](https://wiki.kurokesu.com/uploads/images/gallery/2021-02/scaled-1680-/Kurokesu-TPA2-1,2_.jpg)](https://wiki.kurokesu.com/uploads/images/gallery/2021-02/Kurokesu-TPA2-1,2_.jpg)# Features

- Black anodized aluminium body and stainless steel shaft
- Anti-oxidizing electrical system covered with dielectric fluid
- Modular construction
- Ingress protected against dust and splashes of water from all directions
- Probe is designed with normally closed internal switch contacts
- Shielded flexible cable with quick action connector
- Each probe is tested before being shipped
- Probe is designed with normally closed internal switch contacts
- Concentricity calibration 4 or 3 set screws with included Allen key. Optically calibrated before shipment.
- Standard M3x0.5 probe tip thread# Specifications

<table border="1" id="bkmrk-approach-direction-%C2%B1" style="border-collapse: collapse; width: 100%;"><tbody><tr><td style="width: 50%;">Approach direction</td><td style="width: 50%;">±X, ±Y, ±Z</td></tr><tr><td style="width: 50%;">Repeatability</td><td style="width: 50%;">2 µm</td></tr><tr><td style="width: 50%;">Trigger force</td><td style="width: 50%;">Axial=5 N, Radial=1 N</td></tr><tr><td style="width: 50%;">Weight</td><td style="width: 50%;">160 g</td></tr><tr><td style="width: 50%;">Over travel protection distance</td><td style="width: 50%;">Radial 8mm (with 31mm tip), Axial 5mm</td></tr><tr><td style="width: 50%;">Dimensions</td><td style="width: 50%;">Ø=40 mm, H=35mm, shaft=20mm</td></tr><tr><td style="width: 50%;">Included cable length</td><td style="width: 50%;">3 m</td></tr><tr><td style="width: 50%;">Resistance</td><td style="width: 50%;">Closed = 10-30 Ω, Open = ∞</td></tr><tr><td style="width: 50%;">Shaft diameter</td><td style="width: 50%;">7mm +0.0/-0.05</td></tr></tbody></table># Wiring

Internal electrical TPA2 connection resembles simple switch with normally connected contacts. After stylus is actuated, contacts become disconnected. Signals are isolated from instrument body.

[![wiring2.png](https://wiki.kurokesu.com/uploads/images/gallery/2021-03/scaled-1680-/wiring2.png)](https://wiki.kurokesu.com/uploads/images/gallery/2021-03/wiring2.png)

<table border="1" id="bkmrk-pin-function-1-not-u" style="border-collapse: collapse; width: 100%; height: 145px;"><tbody><tr style="height: 29px;"><td class="align-center" style="width: 50%; height: 29px;">**Pin**</td><td class="align-center" style="width: 50%; height: 29px;">**Function**</td></tr><tr style="height: 29px;"><td class="align-center" style="width: 50%; height: 29px;">1</td><td class="align-center" style="width: 50%; height: 29px;">Not used (unconnected)</td></tr><tr style="height: 29px;"><td class="align-center" style="width: 50%; height: 29px;">2</td><td class="align-center" style="width: 50%; height: 29px;">Signal</td></tr><tr style="height: 29px;"><td class="align-center" style="width: 50%; height: 29px;">3</td><td class="align-center" style="width: 50%; height: 29px;">Signal</td></tr><tr style="height: 29px;"><td class="align-center" style="width: 50%; height: 29px;">4</td><td class="align-center" style="width: 50%; height: 29px;">Not used (unconnected)</td></tr></tbody></table># Dimensions and exploded view

#### Dimensions

[![LP18G-dimensions2.png](https://wiki.kurokesu.com/uploads/images/gallery/2021-02/scaled-1680-/LP18G-dimensions2.png)](https://wiki.kurokesu.com/uploads/images/gallery/2021-02/LP18G-dimensions2.png)

#### Exploded view

[![LP18G-exploded2.png](https://wiki.kurokesu.com/uploads/images/gallery/2021-02/scaled-1680-/LP18G-exploded2.png)](https://wiki.kurokesu.com/uploads/images/gallery/2021-02/LP18G-exploded2.png)

<table border="1" id="bkmrk-iten-nr-part-number-" style="border-collapse: collapse; width: 100%; height: 544px;"><tbody><tr style="height: 29px;"><td class="align-center" style="width: 10.4321%; height: 29px;">**Iten nr**</td><td class="align-center" style="width: 19.6913%; height: 29px;">**Part number**</td><td class="align-center" style="width: 56.3581%; height: 29px;">**Description**</td><td class="align-center" style="width: 13.5185%; height: 29px;">**Qty**</td></tr><tr style="height: 31px;"><td style="width: 10.4321%; height: 31px;">1</td><td style="width: 19.6913%; height: 31px;">Carbide <span class="fontstyle0">ball 5mm</span></td><td style="width: 56.3581%; height: 31px;">Tungsten carbide 5mm ball</td><td style="width: 13.5185%; height: 31px;">6</td></tr><tr style="height: 31px;"><td style="width: 10.4321%; height: 31px;">2</td><td style="width: 19.6913%; height: 31px;"><span class="fontstyle0">LP18G-P0001</span></td><td style="width: 56.3581%; height: 31px;">Aluminium body</td><td style="width: 13.5185%; height: 31px;">1</td></tr><tr style="height: 31px;"><td style="width: 10.4321%; height: 31px;">3</td><td style="width: 19.6913%; height: 31px;"><span class="fontstyle0">LP18G-P0002</span></td><td style="width: 56.3581%; height: 31px;">Stainless steel shank part</td><td style="width: 13.5185%; height: 31px;">1</td></tr><tr style="height: 31px;"><td style="width: 10.4321%; height: 31px;">4</td><td style="width: 19.6913%; height: 31px;"><span class="fontstyle0">LP18G-P0003</span></td><td style="width: 56.3581%; height: 31px;">Aluminium retention ring</td><td style="width: 13.5185%; height: 31px;">1</td></tr><tr style="height: 31px;"><td style="width: 10.4321%; height: 31px;">5</td><td style="width: 19.6913%; height: 31px;"><span class="fontstyle0">DIN 7991 - M3 x 8 8N</span></td><td style="width: 56.3581%; height: 31px;">Set screws</td><td style="width: 13.5185%; height: 31px;">3 or 4</td></tr><tr style="height: 29px;"><td style="width: 10.4321%; height: 29px;">6</td><td style="width: 19.6913%; height: 29px;">YC8<span class="fontstyle0">-4p socket</span></td><td style="width: 56.3581%; height: 29px;"> </td><td style="width: 13.5185%; height: 29px;">1</td></tr><tr style="height: 29px;"><td style="width: 10.4321%; height: 29px;">7</td><td style="width: 19.6913%; height: 29px;">YC8<span class="fontstyle0">-4p connector</span></td><td style="width: 56.3581%; height: 29px;"> </td><td style="width: 13.5185%; height: 29px;">1</td></tr><tr style="height: 29px;"><td style="width: 10.4321%; height: 29px;">8</td><td style="width: 19.6913%; height: 29px;">Stylus</td><td style="width: 56.3581%; height: 29px;">Stylus with M3 thread</td><td style="width: 13.5185%; height: 29px;">1</td></tr><tr style="height: 31px;"><td style="width: 10.4321%; height: 31px;">9</td><td style="width: 19.6913%; height: 31px;">D<span class="fontstyle0">owel pin 3x12</span> </td><td style="width: 56.3581%; height: 31px;">Tungsten carbide dowel pin D=3, L=12</td><td style="width: 13.5185%; height: 31px;">3</td></tr><tr style="height: 31px;"><td style="width: 10.4321%; height: 31px;">10</td><td style="width: 19.6913%; height: 31px;"><span class="fontstyle0">LP18-P0010</span></td><td style="width: 56.3581%; height: 31px;">Custom spring</td><td style="width: 13.5185%; height: 31px;">1</td></tr><tr style="height: 31px;"><td style="width: 10.4321%; height: 31px;">11</td><td style="width: 19.6913%; height: 31px;"><span class="fontstyle0">LP18G-P0005</span></td><td style="width: 56.3581%; height: 31px;">POM spacer</td><td style="width: 13.5185%; height: 31px;">1</td></tr><tr style="height: 31px;"><td style="width: 10.4321%; height: 31px;">12</td><td style="width: 19.6913%; height: 31px;"><span class="fontstyle0">LP18-P0007</span></td><td style="width: 56.3581%; height: 31px;">PCB</td><td style="width: 13.5185%; height: 31px;">1</td></tr><tr style="height: 31px;"><td style="width: 10.4321%; height: 31px;">13</td><td style="width: 19.6913%; height: 31px;"><span class="fontstyle0">LP18G-P0004</span></td><td style="width: 56.3581%; height: 31px;">POM part</td><td style="width: 13.5185%; height: 31px;">1</td></tr><tr style="height: 31px;"><td style="width: 10.4321%; height: 31px;">14</td><td style="width: 19.6913%; height: 31px;"><span class="fontstyle0">LP18-P0008</span></td><td style="width: 56.3581%; height: 31px;">Ingress protection gasket</td><td style="width: 13.5185%; height: 31px;">1</td></tr><tr style="height: 29px;"><td style="width: 10.4321%; height: 29px;">15</td><td style="width: 19.6913%; height: 29px;"><span class="fontstyle0">LP18-P0014</span></td><td style="width: 56.3581%; height: 29px;">O-ring</td><td style="width: 13.5185%; height: 29px;">1</td></tr><tr style="height: 29px;"><td style="width: 10.4321%; height: 29px;">18</td><td style="width: 19.6913%; height: 29px;">Spring pin</td><td style="width: 56.3581%; height: 29px;">Spring loaded contact</td><td style="width: 13.5185%; height: 29px;">6</td></tr><tr style="height: 29px;"><td style="width: 10.4321%; height: 29px;">19</td><td style="width: 19.6913%; height: 29px;"><span class="fontstyle0">LP18G-P0006</span></td><td style="width: 56.3581%; height: 29px;">Aluminium part</td><td style="width: 13.5185%; height: 29px;">1</td></tr></tbody></table>

#### 3D model

Simplified 3D model is [maintained on GitHub](https://github.com/Kurokesu/3d_models)