Search

EP-4739844-A1 - ENHANCED BRAKE FOR A GROUND SAWING MACHINE

EP4739844A1EP 4739844 A1EP4739844 A1EP 4739844A1EP-4739844-A1

Abstract

The present disclosure relates to a ground sawing machine (30) comprising a control unit (210) and a frame (32) supported by rear wheels (34a, 34b) and front wheels (36a, 36b) arranged for enabling moving the ground sawing machine over a surface (38). At least one motor arrangement (40; 6A, 6B) and a saw blade (2) are mounted to the frame, where a first motor arrangement (40) is arranged to propel the saw blade (2) to cut against the surface (38). A rear wheel turning angle (ϕ) is adjustable by means of an actuator (56) that is adapted to pivot a rear wheel axle (46). The ground sawing machine (30) comprises at least one brake block (101, 102) that is fixed or fixedly mounted relative the frame (32), where the actuator (56) is adapted to pivot the rear wheel axle (46) such that at least one rear wheel (34a, 34b) comes into braking engagement with the brake block (101, 102).

Inventors

  • PALLIN, THOMAS

Assignees

  • Husqvarna AB

Dates

Publication Date
20260513
Application Date
20240617

Claims (20)

  1. 1 . A ground sawing machine (30) comprising a control unit (210) and a frame (32) supported by rear wheels (34a, 34b) and front wheels (36a, 36b) arranged for enabling moving the ground sawing machine over a surface (38), where at least one motor arrangement (40; 6A, 6B) and a saw blade (2) are mounted to the frame, a first motor arrangement (40) being arranged to propel the saw blade (2) to cut against the surface (38), where a rear wheel turning angle (cp) is adjustable by means of an actuator (56) that is adapted to pivot a rear wheel axle (46), wherein the ground sawing machine (30) comprises at least one brake block (101 , 102) that is fixed or fixedly mounted relative the frame (32), where the actuator (56) is adapted to pivot the rear wheel axle (46) such that at least one rear wheel (34a, 34b) comes into braking engagement with the brake block (101 , 102).
  2. 2. The ground sawing machine (30) according to claim 1 , wherein the actuator (56) is an electrically controlled actuator.
  3. 3. The ground sawing machine (30) according to claim 1 or 2, wherein the control unit (210) is adapted to control the actuator (56) in dependence of activation of control means (203, 204, 205, 206).
  4. 4. The ground sawing machine (30) according to any one of the previous claims, wherein the control unit (210) is adapted to control the actuator (56) in dependence of activation of brake control means (207), where the control unit (210) is adapted to control the actuator (56) to automatically pivot the rear wheel axle (46) such that at least one rear wheel (34a, 34b) comes into braking engagement with the brake block (101 , 102) upon activation of the brake control means (207).
  5. 5. The ground sawing machine (30) according to any one of the previous claims, wherein the control unit (210) is adapted to control the actuator (56) to automatically pivot the rear wheel axle (46), such that at least one rear wheel (34a, 34b) comes into braking engagement with the brake block (101 , 102) when the ground sawing machine (30) is stopped and/or turned off.
  6. 6. The ground sawing machine (30) according to any one of the previous claims, wherein, when the ground sawing machine (30) is started and/or turned on, the control unit (210) is adapted to control the actuator (56) to automatically reset the rear wheel turning angle (cp) to a previous value that was set before the actuator (56) was controlled to pivot the rear wheel axle (46) such that at least one rear wheel (34a, 34b) comes into braking engagement with the brake block (101 , 102).
  7. 7. The ground sawing machine (30) according to any one of the previous claims, wherein the control unit (210) is adapted to control the actuator (56) in dependence of activation of steering control means (205, 206) such that the wheel turning angle (cp) is set at desired value.
  8. 8. The ground sawing machine (30) according to any one of the previous claims, wherein the control unit (210) is adapted to control the actuator (56) in dependence of activation of automatic course maintaining control means (201 ) such that the wheel turning angle (cp) is automatically set during operation such that the ground sawing machine (30) moves in a predetermined direction.
  9. 9. The ground sawing machine (30) according to any one of the claims 7 or 8, wherein the control unit (210) is adapted to limit the setting of the wheel turning angle (cp) such that no wheel (34a, 34b) comes into braking engagement with the brake block (101 , 102) during operation.
  10. 10. The ground sawing machine (30) according to any one of the previous claims, wherein the actuator (56) is an at least partly manually controlled actuator.
  11. 11. The ground sawing machine (30) according to claim 10, wherein the actuator (56) is displaced by manually turning a nut or a threaded rod.
  12. 12. The ground sawing machine (30) according to any one of the previous claims, wherein said brake block (101 , 102) at least partly is made in metal.
  13. 13. The ground sawing machine (30) according to any one of the previous claims, wherein said brake block (101 , 102) comprises a brake block engagement surface (601 ) that is adapted to engage a wheel outer surface (634).
  14. 14. The ground sawing machine (30) according to claim 13, wherein the brake block engagement surface (601 ) is constituted by a friction layer that is made in at least one of Kevlar, glass, carbon fiber and rubber.
  15. 15. The ground sawing machine (30) according to any one of the previous claims, wherein each brake block (101 , 102) is releasably mounted to a brake block holder (103, 104) that is attached to the frame (32).
  16. 16. The ground sawing machine (30) according to any one of the previous claims, wherein each brake block (101 , 102) has a complementary shape with respect to a wheel outer surface (634) where the brake block (101 , 102) is adapted to contact the wheel outer surface (634).
  17. 17. The ground sawing machine (30) according to any one of the claims 1 -15, wherein each brake block (101 ’) has a tangential extension (E) with respect to a wheel outer surface (634) where the brake block (101 ’) is adapted to contact the wheel outer surface (634).
  18. 18. The ground sawing machine (30) according to any one of the previous claims, wherein the rear wheels (34a, 34b) are adapted to be propelled by a second motor arrangement (6a, 6b).
  19. 19. The ground sawing machine (30) according to any one of the previous claims, wherein the motor arrangement comprises a first electric or hydraulic motor (6a) drivably connected to a first rear wheel (34a) and a second electric or hydraulic motor (6b) drivably connected to a second rear wheel (34b).
  20. 20. The ground sawing machine (30) according to claim 19, wherein the control unit (210) is adapted to control the first motor (6a) and the second motor (6b) to propel the corresponding first rear wheel (34a) and second rear wheel (34b) independently and with either the same rotational velocity or with different rotational velocities.

Description

TITLE Enhanced brake for a ground sawing machine TECHNICAL FIELD The present disclosure relates to a ground sawing machine comprising a frame supported by rear wheels and front wheels arranged to move the ground sawing machine over a surface. At least one motor and a saw blade are mounted to the frame, where at least one motor is arranged to propel the saw blade to cut against the surface. The pointing direction relative the surface of the rear wheels and/or the front wheels is adjustable by means of an electrically controlled actuator. BACKGROUND A self-propelled floor saw can be used to cut into surfaces such as roads and concrete slabs. During setup and operation of the saw, an operator walks behind the saw to control the direction, cutting speed, cutting depth and other operating conditions under which the saw operates. The saw includes a plurality of wheels allowing the saw to move along the surface and a frame supported by the wheels on which is mounted a motor or other power supply for operating a saw blade and often for driving one or more driven wheels to move the saw along the surface. One or more handles extend behind the saw about the level of an operator's hands to allow the operator to manually position and guide the saw. Typically, the saw blade is located at the front of the saw and handles extend behind the saw. For a typical straight cut, the operator aligns the saw blade and often a cutting guide with the intended cutting path. The saw is maneuvered with the saw blade raised above the concrete until the blade and cutting guide are aligned with the cutting path. As the saw blade engages the concrete or other surface to be cut, the blade cuts into the concrete to the desired depth, such as the depth selected by the operator. At the desired depth, the drive wheels are engaged to propel the saw forward to cut the desired slot or groove, which typically follows a straight kerf. Only relying on a braking effect of a motor that is connected to one or more driven wheels may be insufficient in order to avoid undesired movement of a ground sawing machine when not in operation. It is necessary that ground sawing machines are equipped with an efficient parking brake that is uncomplicated and suitably can be retro-fitted to existing concrete saws. It is also desired that ground sawing machines can obtain a high degree of maneuverability and be easily controlled by an operator. This is the case both during a cutting operation and when transporting the ground sawing machine between cutting operations. SUMMARY An objective of the present disclosure is to provide a ground sawing machine with an efficient parking brake function. Another objective is to provide a ground sawing machine with increased maneuverability and easily handled control. The objective is at least in part obtained by a ground sawing machine comprising a control unit and a frame supported by rear wheels and front wheels arranged for enabling moving the ground sawing machine over a surface. At least one motor arrangement and a saw blade are mounted to the frame, a first motor arrangement being arranged to propel the saw blade to cut against the surface, where a rear wheel turning angle is adjustable by means of an actuator that is adapted to pivot a rear wheel axle. The ground sawing machine comprises at least one brake block that is fixed or fixedly mounted relative the frame, where the actuator is adapted to pivot the rear wheel axle such that at least one rear wheel comes into braking engagement with the brake block. In this manner, a parking brake is provided where the ground sawing machine can be reliably braked and left when not in use without risking the ground sawing machine moving in an uncontrolled manner. Furthermore, one or more brake blocks can be added to existing machines, requiring only minor modifications to allow said brake blocks to be mounted in a correct position. According to some aspects, the actuator is an electrically controlled actuator. According to some further aspects, the control unit is adapted to control the actuator in dependence of activation of control means. This means that the actuator can be accurately controlled in a reliable manner. According to some aspects, the control unit is adapted to control the actuator in dependence of activation of brake control means, where the control unit is adapted to control the actuator to automatically pivot the rear wheel axle such that at least one rear wheel comes into braking engagement with the brake block upon activation of the brake control means. This means that the brake is activated by an operator that activates the braking control means, for example by pressing a brake button on the sub-panel. According to some aspects, the control unit is adapted to control the actuator to automatically pivot the rear wheel axle such that at least one rear wheel into braking engagement with the brake block when the ground sawing machine is stopped and/or turned off. T