PERCUSSION APPARATUS PROVIDED WITH A GUIDE BEARING EQUIPPED WITH A CENTERING DEVICE

• US 20190314969A1
• Filed: 09/26/2017
• Published: 10/17/2019
• Est. Priority Date: 10/14/2016
• Status: Active Grant

• Current Assignee: Montabert Co. (Trane Technologies plc)
• Original Assignee: Montabert Co. (Trane Technologies plc)
• Inventors: COMARMOND, Jean-Sylvain
• Granted Patent: US 11,383,368 B2
• Time in Patent Office: Days
• CPC Class Codes: B25D 2217/0023 Pistons
• CPC Class Codes: B25D 2250/121 Housing details
• CPC Class Codes: B25D 2250/125 Hydraulic tool components
• CPC Class Codes: B25D 2250/231 Sleeve details
• CPC Class Codes: B25D 2250/331 Use of bearings
• CPC Class Codes: B25D 9/12 comprising a built-in liquid motor , i.e. the tool being driven by hydraulic pressure
• CPC Class Codes: B25D 9/145 for hydraulically actuated hammers having an accumulator
• CPC Class Codes: B25D 9/18 involving a piston-type slide valve
• CPC Class Codes: B25D 9/26 Control devices for adjusting the stroke of the piston or the force or frequency of impact thereof control systems adapted for earth drilling E21B44/00
• CPC Class Codes: F16C 2316/10 in medical appliances, e.g. in diagnosis, dentistry, instruments, prostheses, medical imaging appliances
• CPC Class Codes: F16C 2370/00 Apparatus relating to physics, e.g. instruments in general G01 - G12
• CPC Class Codes: F16C 32/06 with moving member supported by a fluid cushion formed, at least to a large extent, otherwise than by movement of the shaft, e.g. hydrostatic air-cushion bearings
• CPC Class Codes: F16C 32/0655 of supply openings
• CPC Class Codes: F16C 32/0659 of pockets or grooves

Abstract

This percussion apparatus includes a striking piston mounted so as to be displaced inside a piston cylinder and arranged to strike a tool; and a guide bearing comprising a guide surface configured to guide the striking piston during the displacements of the striking piston in the piston cylinder. The guide bearing includes a centering device configured to center the striking piston in the piston cylinder, the centering device comprising centering chambers formed in the guide surface and distributed around the striking piston, each centering chamber being fluidly connected to a high pressure fluid supply circuit; and at least one discharge groove formed in the guide surface of the guide bearing and located proximate to at least one of the centering chambers, the at least one discharge groove being fluidly connected to a low pressure circuit.

Claims

1. A percussion apparatus, including:

a body comprising a piston cylinder,

a striking piston mounted so as to be displaced alternately inside the piston cylinder, and arranged to strike a tool,

at least one guide bearing comprising a guide surface configured to guide the striking piston during displacements of the striking piston in the piston cylinder, a functional clearance being provided between the guide surface and the striking piston,

a high pressure fluid supply circuit and a low pressure circuit,

characterized in that the at least one guide bearing includes a centering device configured to center the striking piston in the piston cylinder, the centering device comprising;

a plurality of centering chambers formed in the guide surface of the at least one guide bearing and distributed around the striking piston, each centering chamber being fluidly connected to the high pressure fluid supply circuit, and

a plurality of discharge grooves formed in the guide surface of the at least one guide bearing, each discharge groove being located proximate to at least one of the centering chambers and being fluidly connected to the low pressure circuit, the plurality of discharge grooves including at least two discharge grooves which are annular and which extend around the striking piston and respectively on either side of the centering chambers.

2. The percussion apparatus according to claim 1, wherein the centering chambers are evenly distributed around the striking piston.

3. The percussion apparatus according to claim 1, wherein the centering chambers are aligned on a same circumference of the guide surface.

4. The percussion apparatus according to claim 1, wherein the centering device is configured to supply each centering chamber with a substantially constant supply flow rate.

5. The percussion apparatus according to claim 1, wherein the centering device includes a plurality of connection channels each provided with a flow rate control member, each connection channel fluidly connecting the high pressure fluid supply circuit to a respective centering chamber.

6. The percussion apparatus according to claim 5, wherein each flow rate control member is a calibrated orifice.

7. The percussion apparatus according to claim 1, wherein the centering device includes a plurality of discharge channel, each discharge channel fluidly connecting the low pressure circuit to a respective discharge groove.

8. The percussion apparatus according to claim 1, which further comprises a control distributor configured to control an alternating movement of the striking piston inside the piston cylinder alternately following a strike stroke and a return stroke.

9. The percussion apparatus according to claim 8, wherein the striking piston and the piston cylinder delimit a first control chamber permanently connected to the high pressure fluid supply circuit and a second control chamber, the control distributor being configured to alternately put the second control chamber in connection with the high pressure fluid supply circuit and the low pressure circuit.

10. The percussion apparatus according to claim 1, which comprises at least two guide bearings axially offset with respect to one another, each of the guide bearings including a centering device configured to center the striking piston in the piston cylinder.

11. The percussion apparatus according to claim 2, wherein the centering chambers are aligned on a same circumference of the guide surface.

12. The percussion apparatus according to claim 2, wherein the centering device is configured to supply each centering chamber with a substantially constant supply flow rate.

13. The percussion apparatus according to claim 4, wherein the centering device is configured to supply each centering chamber with a substantially constant supply flow rate.

14. The percussion apparatus according to claim 11, wherein the centering device is configured to supply each centering chamber with a substantially constant supply flow rate.

15. The percussion apparatus according to claim 14, wherein the centering device includes a plurality of connection channels each provided with a flow rate control member, each connection channel fluidly connecting the high pressure fluid supply circuit to a respective centering chamber.

16. The percussion apparatus according to claim 15, wherein each flow rate control member is a calibrated orifice.

17. The percussion apparatus according to claim 16, wherein the centering device includes a plurality of discharge channels, each discharge channel fluidly connecting the low pressure circuit to a respective discharge groove.

18. The percussion apparatus according to any one of claim 17, which further comprises a control distributor configured to control an alternating movement of the striking piston inside the piston cylinder alternately following a strike stroke and a return stroke.

19. The percussion apparatus according to claim 18, wherein the striking piston and the piston cylinder delimit a first control chamber permanently connected to the high pressure fluid supply circuit and a second control chamber, the control distributor being configured to alternately put the second control chamber in connection with the high pressure fluid supply circuit and the low pressure circuit.

20. The percussion apparatus according to claim 19, which comprises at least two guide bearings axially offset with respect to one another, each of the guide bearings including a centering device configured to center the striking piston in the piston cylinder.