US3747142A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Broken tool detector
Assignee: Valhi Inc
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Filing: 1972-04-10
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Granted: 1973-07-24
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Expires: 1992-04-10
Abstract
Abstract A broken tool detector utilized to check for the presence of any protrusion on the face of a tool, such as the second blow punch on a two blow header or similar machine, where the detector includes a probe which travels with the ram and is mounted on the ram on which the punches are mounted. The probe is positioned so that the second punch passes it as the punch is moved between its inactive and active punching positions. The probe is isolated electrically from the machine and wired to a low voltage circuit connected to the drive motor starter circuit by isolated detector relay contacts. Each time the probe contacts the end of the punch, a capacitor charge is restored which supplies energy to maintain the detector relay contacts. If the punch is broken or worn and fails to make contact with the probe, the capacitor discharges and the detector relay drops out, stopping the machine.
Inventors
- 👤 R Arbogast
- 👤 R Neuroth
- 👤 J Haight
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 12:53
CPC Classifications
B; B23; B23B; B23B49/00; B23B49/001; B21; B21J; B21J13/00; Y; Y10; Y10T; Y10T83/00; Y10T83/081; Y10T83/088
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
139 words
A broken tool detector for an automatic machine having elements movable in continuously repeating cycles for performing operations on workpieces, comprising an elongated probe mounted on the machine to make contact with the end of a tool at at least one point during the time of a cycle of the machine, and an electrical circuit including the probe, the tool and a detector relay for controlling the machine, and a capacitor in parallel with the detector relay, whereby, when the probe contacts the tool, voltage in the circuit actuates the detector relay and the capacitor by means of a controlled rectifier and, if the tool is broken, the capacitor is charged from the previous cycle to retain the detector relay actuated until the voltage in the capacitor drops below a minimum value, at which time the relay is deenergized.
Claim 2
Dependent Claim
139 words
A broken tool detector for an automatic machine having elements movable in continuously repeating cycles for performing operations on workpieces, comprising an elongated probe mounted on the machine to make contact with the end of a tool at at least one point during the time of a cycle of the machine, and an electrical circuit including the probe, the tool and a detector relay for controlling the machine, and a capacitor in parallel with the detector relay, whereby, when the probe contacts the tool, voltage in the circuit actuates the detector relay and the capacitor by means of a controlled rectifier and, if the tool is broken, the capacitor is charged from the previous cycle to retain the detector relay actuated until the voltage in the capacitor drops below a minimum value, at which time the relay is deenergized.
Claim 3
Dependent Claim
35 words
A broken tool detector as set forth in claim 1, in which the machine and the tool are grounded and the probe is electrically insulated from the machine but is electrically connected to the circuit.
Claim 4
Dependent Claim
58 words
A broken tool detector as set forth In claim 2, including a reciprocating ram in the machine, said probe and the tool being mounted on the ram, and the tool is adapted to move laterally past the probe in shifting between inactive and active positions, the probe contacting the end of the tool during each lateral movement thereof.
Claim 5
Dependent Claim
40 words
A broken tool detector as set forth in claim 3, including an alignment block, said probe being adjustably mounted on the alignment block, and a non-conductive elongated body is mounted on the ram and is secured to the alignment block.
Claim 6
Dependent Claim
41 words
A broken tool detector as set forth in claim 4, including a conductive contact bar mounted in the nonconductive body and connected to said probe, and a stationary brush or brushes slidably engaging the contact bar is connected to the circuit.
Claim 7
Dependent Claim
102 words
A broken tool detector as set forth in claim 4, including a punch contact carrying the probe, a front bar having the punch contact secured at one end and the other end slidably received in the lower end of the alignment block, a push-pull screw mounted for rotation on the front bar and threadingly engaging the alignment block for adjustment of the front bar and the probe relative to the alignment block, and a clamping bolt in the alignment block and threadingly engaging the front bar adjacent its inner end to clamp the front bar in adjusted position on the alignment block.
Claim 8
Dependent Claim
58 words
A broken tool detector as set forth in claim 2, in which said circuit includes a source of low DC voltage, and a controlled rectifier in series with the detector relay and connected to the probe contact, whereby closure of the probe contact triggers the rectifier to provide voltage to energize the detector relay and charge the capacitor.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-07-23 | 1977-01-22 | 1977-07-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-23 | 1981-01-22 | 1981-07-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-23 | 1985-01-22 | 1985-07-24 | $7700.00 | Window Closed / Lapsed |